ML17172A199

Attachment 10 - 30441R00041, Revision a, Reactor-Based Molybdenum-99 Supply System Project, Critical Heat Flux Testing at the University of Wisconsin Final Report

ML17172A199
Person / Time
Site:	University of Missouri-Columbia
Issue date:	04/14/2017
From:	Stone J General Atomic Co
To:	Office of Nuclear Reactor Regulation, Nordion (Canada), US Dept of Energy, National Nuclear Security Admin
Shared Package
ML17172A205	List: ML17172A195 ML17172A199
References
DE-NA0002773 30441R00041, Rev. A
Download: ML17172A199 (98)

Text

Attachment 10

..{ RELEASED 30441 R00041 COM Apvd 2017/04/14 Revision A REACTOR-BASED MOLYBDENUM-99 SUPPLY SYSTEM PROJECT CRITICAL HEAT FLUX TESTING AT THE UNIVERSITY OF WISCONSIN FINAL REPORT Prepared by General Atomics for the U.S. Department of Energy/National Nuclear Security Administration and Nordion Canada Inc.

Cooperative Agreement DE-NA0002773 GA Project 30441 WBS 1250

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A REVISION HISTORY Revision Date Description of Changes A 14APR17 Initial Release POINT OF CONTACT INFORMATION PREPARED BY:

Name Position Email Phone J. Stone Engineer josh .stone@ga.com 858-455-3617 APPROVED BY:

Name Position Email Phone B. Schleicher Chief Engineer Bob.Schleicher@ga .com 858-455-4 733 K. Murray Project Manager Katherine .Murray@ga.com 858-455-3272 K. Partain Quality Engineer Katherine.Partain@ga .com 858-455-3225 DESIGN CONTROL SYSTEM DESCRIPTION

~

R&D DISC QA LEVEL SYS DV&S D DESIGN D T&E N I N/A D NA ii

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Preface This report was written by the University of Wisconsin for GA under GA Purchase Order (PO) 4500063597 and is being released in its entirety through the GA Configuration Management System.

Executive Summary The results compiled by the University of Wisconsin (UW) on the convective behavior of a rod cooled by water at high mass flux and high heat flux are the best possible representation of the cooling performance of the SGE target rods, and provide an anchor for the safety case with regard to the critical heat flux (CHF) margin. In total, the results of the test demonstrated (i) a more than adequate critical heat flux ratio (CHFR) exists for the expected operating conditions, (ii) the resiliency of the CHFR under extreme operating conditions beyond those that could be expected in MURR, and (iii) minimal vapor generation takes place under expected operating conditions. This is important to MURR's licensing effort, as outside of the data acquired from this experiment there is very little information in the literature to help predict the boiling behavior in the design flow regime for the SGE targets .

The test apparatus devised by UW team was an excellent representation for the SGE target cartridge . Its hydraulic diameter matches that of a center-channel SGE rod to within one percent, and instrumentation allows for the control of the critical flow parameters of mass flux ,

heat flux , temperature and pressure . Notwithstanding these features, the UW test apparatus is not a perfect replica . The heater tube used to simulate the fission in the SGE pin is heated via electrical resistance, which creates a uniform axial heat flux profile , not a cosine-shaped profile expected in the MURR core . The differences were accounted for by monitoring the flow conditions at the heated section outlet, which is very close to where the critical heat flux occurs (for a uniform heat flux profile). The outlet pressure was easily controlled to desired values .

However, the outlet temperature was could not be kept stable for long periods of time at high heat inputs, as the cooling of the primary coolant reservoir was limited by the secondary cooling system's chiller outlet temperature. Therefore , the heater was intermittently turned off to allow the reservoir to cool and keep the outlet temperature close to the desired values .

Using the outlet conditions to correlate the observed CHFs to those predicted by Groeneveld's table produced excellent agreement. All observed CHF values were within 10% of Groeneveld's predicted values. This was expected , as Groeneveld 's publication notes that these regions in his table should accurately predict CHF conditions .

The UW test also provided important data regarding the amount of vapor generation expected at nominal operating conditions. Overall, that data confirms GA's previous assessment that the ~

vapor generation amount will be small, with vapor volume fractions of approximately - at ~

the maximum heat flux location. This value is slightly higher than the vapor fraction calculated iii

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041/A from Del Valle and Kenning 's data 1 , which was also on the order o f ** and significantly higher B d f a, , e, than the amount predicted by ANSYS FLUENT's RPI boiling model (about - ) as documented in GA Report 30441R00033/B 2 .

There are two plausible explanations why the FLUENT model underestimates the vapor generation. First, the uniform heat flux profile should increase the vapor generated , as the entire rod is operating at the maximum heat flux . This effect is more pronounced the further downstream the flow travels, as bubbles generated over the length of the tube accumulate.

Second, the FLUENT boiling model is typically applied to lower heat and mass fluxes, and is not likely to be calibrated to the conditions of the SGE target rods. The FLUENT verification case examined in GA Report 30441R00028/A 3 used a mass flux of 900 kg/(s*m 2 ) and a heat flux of~

0.57 MW/m 2 , compared to the target design's nominal values of and - ~

- respectively. In a study by Colombo and Fairweather 4 comparing the results of 20 experiments to a similar computational fluid dynamics (CFO) boiling model, none of the reference experiments exceeded mass flux of 3000 kg/(s*m 2 ) and heat flux of 1.2 MW/m 2 . This demonstrates the general dearth of existing data for subcooled nucleate boiling around the SGE rods' operating parameters , which is why the UW CHF experiment was needed to verify GA's design performance.

As stated in GA Report 30441 R00033/B 2 , the data of Del Valle and Kenning provided the closest match to GA's SGE rod operating conditions. The UW experiment confirmed two of their previous observations: that flow remains bubbly up to burnout under high subcooling , and that the bubbles are small. However, unlike in some of the other literature references , which reported bubbles growing and collapsing in place, the bubbles in the UW experiment clearly traveled with the flow. This difference is likely due to the fact that GA's test conditions utilized higher coolant velocities than the experiments reported in the literature. The bubbles traveled relatively slowly compared to the bulk coolant, which indicates the bubbles remain close to the cladding , per the velocity profile in Appendix A of 30441R00038/A 5 .

Regardless of the differences between the test results, the literature, and predictions from FLUENT, the data gathered by UW ultimately confirms that the conditions for the SGE target rod cooling provide a more than adequate margin of safety. Videographic study confirms that ~

the vapor volume fraction in the coolant , the observed CHF values ~

provide CHFR values of greater than 2 for conditions much more extreme than will be allowed in 1

International Journal of Heat and Mass Transfer 28 (1985) 1907-1920 2

GA Report, "Analysis of Forced Convection Cooling of Target Rods with 2 Phase Considerations,"

30441 R00033/B, 25 January, 2017 3

GA Report. "FLUENT (Version 16. 0) Software Verification Test Report," 30441 R00028/A, 10 August 2016 4

International Journal of Heat and Mass Transfer 103 (2016) 28-44 5

GA Report, "Computational Fluid Dynamics of Target Housing Design Calculation Report,"

30441R00038/A, 25 January, 2017 iv

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A the SGE target. In short, the UW CHF testing has provided GA with full confidence that SGE target cooling design provides more than adequate safety margins, even with the high power rating of the target rods inducing a small amount of subcooled nucleate boiling .

v

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA WISCONSIN UNIVERSITY OF WISCONSIN-MADISON Critical Heat Flux Testing Direct (Resistance} Heated Rod 0.635cm O.D. Rod in 1.67cm l.D. Glass Tube Maximum Heat Flux of 9.6 Mw/m/\2 January 4- February 27, 2017 University of Wisconsin, Thermal Hydraulics Laboratory Figure 2: End View of Experiment Figure 1: Side View of Experiment Paul Brooks, Bryan Coddington , Julianna Duarte, Phillip Buelow Mike Corradini and Mark Anderson Contact information :

Mark Anderson Director University of Wisconsin - Thermal Hydraulics Laboratory 737 Engineering Research Bldg 1500 Engineering Dr, Madison *w1 53706 Phone: 608-263-2802 e-mail : manderson@engr.wisc.edu 1

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Table of Content:

Introduction:

Page3 System

Description:

Page3 Flow Path

Description:

Page4 Heated Rod Assembly: Pages Test Section: Page6 Optical Imaging Page9 Power Supply Page9 Pressure Measurements: PagelO Void Fraction Measurements: PagelO Operation: Page13 Individual Experiment Descriptions: Page14 Results: Page35 Discussion : Page38 Appendices

1. 1, TRACE Code Calculations Page39

1. 2, Operational Procedure Page52

1. 3, Sample Error Calculations Page SS

1. 4, Instrument Calibrations Page SS

1. 5, Void Generation Reference Page69

1. 6, Rod Surface Roughness Page71

1. 7, List of Experimental Runs Page75

1. 8, Mechanical Drawings Page79

1. 9, Computer Platform and Software Page89 2

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A

Introduction:

This report describes experimental studies of critical heat flux values conducted for conditions encountered in open pool test reactors with forced water flow. Testing was conducted at the University of Wisconsin thermal hydraulic lab during January and February of 2017 . The objective of this work was to produce CHF at various pressures and temperatures typical of research reactors, and to then compare these results with 6

Groeneveld et al. (2007) look up table .

System

Description:

Reservoir Test Section By-pass Heat Exchange! j}. Valve Loop Pump (Closed)

(VFD)

Coriolis Flow Meter ~

~FF;===~==========llPI ~

Figure 3: Labeled Drawing, Overall Side View These test were conducted on the University of Wisconsin, Thermal Hydraulics Lab critical heat flux testing rig . The rig consists of an insulated, stainless steel upper reservoir l.23m in diameter by l.7m length .

During testing this upper reservoir was filled with deionized water to a level slightly above the return port from the test section, containing approximately l.SmA3(400gallons) of water. This water was maintained at 3-7mohm of purity via a mixed bed deionizing filtration system. The thermal energy from the testing was rejected through a water to glycol heat exchanger attached to the system. The flow through the (experimental) water side of this heat exchanger was forced with a 2.2kw (3hp) stainless steel centrifugal pump, which was controlled via a variable frequency drive. This flow was maintained at approximately 0.21mA3/m [SS gpm] through all testing . This flow also contributed to the mixing of the upper reservoir to maintain steady test section inlet temperatures . The flow through the glycol side (facility side) of the heat exchanger was controlled via flow and bypass valves. The heated glycol was directed to a roof mounted chiller where the experimental heat was ultimately rejected.

6 6 D.C ., Groeneveld, J.Q. , Shan, A.Z., Vasic, L.K.H. , Leung , A. Durmayza, J. Yang , S.C. , Cheng , A.

Tanase, 'The 2006 CHF look-u table", Nuclear En ineerin and Desi n 237 2007 1909-1922 3

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Flow Path

Description:

.....--1'Retum To Supply From

"---y'Reservor Reservoir 2"NPS 3"NPS

'Z'NPS Exit Valve n

Bypass Valve (Closed)

Figure 5: Picture, Flow Path Centrlfugal Pump Figure 4: Drawing, Labeled Flow Path Water is supplied to the test section circuit via a 3" NPS bottom tap from the upper reservoir. The supply water from the tank flows downward 0.6m through the 3" NPS supply pip ing, and then proceeds into a 1.5" NPS branch pipe. This pipe proceeds horizontally then downward into the 1.5" NPS intake of a centrifugal, 3 hp, stainless steel pump . The water is then propelled upward from the pump through a 1.5" pipe, through a 135-degree bend and into the main 3" NPS supply line. The flow proceeds through 0.5m length of the 3" NPS, through a 3" NPS flange set, and into an eccentric reducer set ending in a 0.75" NPS, 1501b, RF flange. This flange is mated to the Foxboro Coriolis flow meter, model CFTl0/15, last calibration date of 7/11/16 . The water flows through the Coriolis, through another 0.75" NPS flange set, and into a 0.75" NPS to 1" NPS concentric reducer (used as diffuser) . The flow then proceeds through l.3m of 1" NPS schedule 40 horizontal pipe to a matching long radius 1" NPS upward turning go* elbow. The flow then proceeds upward through a 1" NPS full port, pneumatically driven ball valve, through a 1.25" Swagelok straight union and into the test section .

The flow exits the top of the test section through the horizontal branch of a 2" NPS, schedule 40, butt weld tee. A 2" NPS schedule 40, go* upward turning elbow is directly welded to this tee . The flow then proceeds through a 2" hose size cam lock fitting, through 1.5 meters of 2" ID hose and into an additional 2" hose size cam lock fitting . This fitting is directly coupled to a 2" NPS, pneumatically driven ball valve which is attached to the end of the main tank via a 2" NPS schedule 40, 0.15m length pipe section. The water is returned to the upper reservoir through thi s 2" NPS pipe, into an end flange of the tank, just below the water surface in the tank.

All piping, fittings, pumps, tanks, flowmeters, and heat exchangers are constructed of 300 series stainless steel. All wate r hoses used in the system were either EPDM or NBR. The two pneumatically operated ball valves were installed to both isolate the test section in the event of a failure of the glass tube, and to allow work on the test section without draining the upper reservoir. A failure of the glass tube did not occur.

4

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Heated Rod Assembly:

Lower Copper Fitting I r Lower Copper Lead

/

Lower Voltage*' S. ense Wire lnconel 625 Heater Element

-rr::::1

_/

I I H

1 I

~

/

Internal Thermocouples (2)

Upper Voltage Sense W ire

,'.:::::::::::::4

.-~

II J '

Figure 6: Diagram of Heater Assembly A custom heater was designed Upper Copper Lead and six were fabricated Upper Copper Transition to complete the Upper Copper Tube requested testing . The heater was designed to convey a maximum of 1200 amps, a maximum of 80volts, and create 2

greater than 9Mw/m heat flux. The method used to create the heat flux was direct ohmic h e a t i n B of the tubular lnconel 625 element. The element was 0 . 2 ~' (6 .35- mm) outside 5a , d, e, f diameter, with a nominal wall thickness of .02" (0.5 1mm), and an overall length of 17.97" (456mm) . The uniformity of the electrical resista nce of the original stock was checked resulting in a standard deviation over lOOmm lengths of less than 1.85%. Heaters #1 and #2 were also checked for uniformity of electrical resistance along the length of the heater rod, at intervals of 1" (25.4mm), resulting in standard deviations of 1.6% and 1.2% respectively. The surface of the inconel tube wa s polished with Scotch -Brite, #7447, very fine, maroon hand pad . Heaters #1 and

1. 2 surface roughnesses were measured after testing, heaters #3, #4, and #5 were measured before and after testing, and heater #6 was only measured before testing. The results are presented in appendix 6.

The lower end of the heater assembly consisted of a "lower copper fitting" with a Y.-13 thread on the lowest end, a 0.25" socket on the upper end, and a flange with wrench flats in the center. The 0.25" diameter round "lower copper lead" was soldered into the socket of the " lower copper fitting" . The upper 0.12 5" (3 .2mm) of the "l ower copper lead" had a reduce d diameter for a slight interference fit into the bottom of the heater element. The heater element wa s soldered onto this boss. The rod was then filled with approximately 10 grams of tightly packed verm icu lite.

Two 0.02" (0 .51mm) diameter holes were then drilled into the vermiculite, from the top of the heater rod, at the outside edge of the vermicu lite, 0.5 (12 .7mm) deep as measured from the end of the rod, at azimuthal angle of 180 degrees relative to each other.

The top of the heater assembly consisted of a 0.625" (15 .9mm) outside diameter " upper copper tube" with a 0.121" (3 .lmm) wall and a length of approximately 19" (483mm) . Beneath this, the " upper copper transition" fit into the " upper copper tube" on the top end, had a socket on Figure 7: the lower end to receive the upper coppe r lead, and a bore through of 0.094" (2 .39mm) diameter.

Picture of The upper copper lead was tubular, with a 0.25" (6.35mm) outside diameter, and 0.094" (2 .39mm)

Heater on Jig inside diameter. The lower 0.125" (3 .2 mm) of the "u pper copper lead" had a reduced diameter for a slight interference fit into the top of the heater element . These three components were soldered together and two Omega TJC 36-CAIN -020U-36 thermocouples of 0.02" (0.51mm) diameter with fiberglass sleeves were fed through the upper assemb ly from the top.

The tips of the thermocouples were forced into the dri ll ed holes in the vermiculite packing, the lower end of the "up per copper lead" was pressed into the upper end of the heater element, and this final joint was soldered .

With the heater assembly complete, 2 Belden (part number 83026 001) 16 gauge wires 0.0625" (1.6mm) outside diameter wires were soldered onto the copper leads fo r voltage sensing to calculate actual power. All copper power conducting joints were soldered with Harris STAY-SILV white flux and Harris Saftey-Silv 56 solder, utilizing a 5

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A precision oxy-acetylene torch as the heat source . The two voltage sensing wires were soldered to the copper leads with Oatey No. 95 lead free t inning flux and Sn63/Pb37 solder utilizing the same heat source as above .

Test Section:

Loww Pressure Tap

~ Lower Vob91 Sense

=--- L...., Elt'""81 Conne-.S(Ground. l ol 2)

Lower AanQe Set Figure 8: Labeled Solid Rendering of Test Section Figure 9: Picture Test Section Figure 11 : Cut-away of Lower Test Section Figure 12: Rendering of Top Figure 10: Cut-away of Upper of Test Section Test Section 6

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Water is supplied to the test section from the bottom via a

,,,,,- Upper Electrical Connections horizontal 1" NPS schedule 40 pipe. As the flow approaches and flows Upper Exit Thermocouple through the upward turning long radius 1" NPS elbow, it passes around the lower inlet thermocouple. This was a calibrated thermocouple, manufactured by Omega, model number KMQ316SS-125U-12-CAL-3, ID#

OM -121123315-2, 0.125" (3 .2mm) diameter, k-type, sheathed, and ungrounded, inserted to a minimum in-pipe depth of 2" (51mm).

Once through the elbow, the flow passed through a 1" NPS full

/

la.. l.oc:elien.

1!..1111911liblna port ball valve and then through a 1.25" tube size union. From the union, the flow proceeded upwards through a 1" NPS - 2" NPS schedule 40 L Gauge Location Runs 1 &2 reducer (used as diffuser) . The large end of this reducer was directly Lower Electrical Connections welded to the cu stom 2" NPS, 150# blind flange . This custom blind flange contained a Y.- 13 tapped hole in the center to receive the lower

~ 1.25" Swagelok Union

\-..Jo,CI~ . '*<:= 1"NPS Ball Valve end of the test section and 4 ports machined through to allow water flow . Additionally an 0 -ring groove was machined into the blind flange Lower Inlet Thermocouple to allow sealing to t he mating flange, and two sta inless lugs were welded Figure 13: Labeled Diagram of Test Section to the outer rim to allow electrical connections .

A weld neck 2" NPS 150# flange wa s fixed above with 4 bolts. A custom reducer was directly welded to this flange . This custom reducer was machined with a large diameter of 2.067" (52 .5mm) to match the lower flange, a small diameter of 0.656" (16 .66mm) to match test section, and an included angle of 60 degrees on the taper. In the tapered section, this reducer had four equally spaced radial ports tapped 6-32 for rod locating pins . At this same elevation, two additional ports 0.125" (3 .2mm) diameter we re equa lly spaced between the locating pin ports .

These two ports were utilized for the voltage sensing wire and the nea r rod inlet thermocouple . The near rod inlet thermocouple was inserted so the t ip was approximately 0.125" (3 .2mm) from the "lower copper Figure 15: Picture of Figure 14: Picture of lead" leaving approximately 0.56" (14 .2mm) wetted length. This Lower Flange Lower Flange calibrated thermocouple was manufactured by Omega, model number KMQ316SS-062U CAL-4-3P, ID#OM-121123377-1, 0.0625" (l.59mm) t11a- 0iam.* r NH r Rod Top diameter, k-type, sheathed, and ungrounded .

T...,,,,.....plo This reducer also contained a 0.656" (16 .66mm) diameter throat section. A 0.0625" (l.59mm) diameter hole was drilled in this throat section to allow for the pressure tap at the inlet condition s. To allow for acceptable sealing to the glass tube a cu stom Ultra-Torr 0 -ring type fitting was welded directly to the small end of the tapered section . This fitting was modified so the through bore matched the glass tube inside diameter.

The outside of the test section was made from a glass tube to allow flow visualization . Six of these precision bore borosilicate glass tubes were purchased from Wilmad-Labglass/SP Scienceware, part

~

' "2-NPS. 160l 318SS number P-. 656-.985-0-28 .

CusDm Bln::I Ainge

• -t "NPS Figure 16: Labeled Diagram of Test Section The bore on this glass was Con e. AlduOll' 7

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A specified at 0.65~' (16.6~mm) and the outside ~

diameter was specified at 0.985" (25.02mm) . The inside diameter was ~

measured with a telescoping gauge and micrometer and found to be within the factory specification . The glass tube was cut on a diamond saw to the desired length and the ends were flame polished before assembly into the test section .

At the top end of the glass an identical Ultra -Torr fitting was used to seal. This fitting was directly welded to a custom taper section similar to the one located at the entrance to the rod . The upper taper section again had the pressure tap machined in the throat, the four radial holes in t he taper to accommodate locating screws (to keep the rod centered), identical diameters, and identical taper angle. A 2" NPS, 150#, schedule 40 bore weld neck flange (with 0 -ring groove) was directly welded to the large, upper end of the custom taper section .

Figure 17: Picture of Lower Test Section Two 0.125" (3 .2mm) diameter radial ports were machined into the neck of this flange . One port was utilized for the voltage sensing wire, while the nea r rod exit thermocouple was inserted into the other port. This thermocouple was inserted so the tip was approximately 0.125" (3 .2mm) from the " upper copper lead" leaving approximately 0.79" (20 .lmm) wetted length . Th is calibrated thermocouple was manufactured by Omega, model number KMQ316SS-062U-18-CAL-4-3P, ID#OM-121123377-2, 0.0625" (l.59mm) diameter, k-type, sheathed, and ungrounded .

An additional mating 2" NPS weld neck flange was fixed to the above assembly with fou r bolts. A 2" NPS schedule 40 butt weld tee, through end, was welded to the pipe end of this flange . A cap was welded to the upper end of this tee. The cap had a hole bored through the end and a custom fitting welded on top to both seal and electrically isolate the upper copper tube of the heater rod assembly.

The branch of this tee had an upward turning 90-degree long radius butt weld elbow, directly welded on. As the water flowed through th is tee it flowed aroun d the upper exit thermocouple . This was a calibrated thermocouple, manufactured by Omega, model number KMQ316SS-125U CAL-3, ID# OM -121123315-1, 0.125" (3 .2mm) diameter, k-type, sheathed, and ungrounded, inserted to a minimum in-pipe depth of 2" (51mm) . A 2" hose camlok fitting was directly welded to the top of this elbow to return flow to the tank.

The thermocouple readings of the DAQs were verified via a calibrated Omega HH506A thermocouple reade r, with a maximum error of 0.3 C.

Figure 18: Picture of Upper Test Section 8

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Optical Imaging:

The heater rod was enclosed in a borosilicate glass tube to allow optical imaging of void generation and critical heat flux events. The glass tube length and location allowed imaging on the entire length of the heated surface. Imaging was conducted with three cameras. The first was a Nikon 07000 SLR with a lOSmm Nikkor micro lens. This was located approximately 4' (1.2m) from the test section and recorded standard video imaging of testing at 24 frames per second as well as still images. The second camera was an Integrated Design Tools Incorporated (IDTI), model HS3-M -4, serial number 23-0405-0007, high speed video camera, with a Nikkor lOSmm lens. This camera was also located approximately 5' (1.5m) from the test section, and recorded a large portion of the heater rod at 500 frames per second . The third camera was an Ametek Phantom model v1211, serial number 18092, high speed camera with a similar 105mm micro lens used for near imaging a small portion of the rod for detail. The lens of this camera wa s located approximately 8.75" (0.22m) from the test section and recorded at 12,696 frames Figure 19: Picture of Experimental Set-up per second . A pair of Lowel P2-10 Pro-Lights were used for illumination.

Power Supply:

Figure 20: Upper Power Figure 2 1: Lower Power Connection Connection Power was provided to the heater element via a Miller PS-100, serial number JH249574 plasma spray power supply. The power supply is rated at 100% duty cycle for a maximum of 1200 amps direct current at 80 volts . The power supply was operated in controlled current mode. The current demand signal was manually entered into the National Instruments DAQ program by the operator (excepting first two experiments where an auto stepped ramp was used) . Current was carried from the negative lead of the power supply, through a calibrated shunt, and to the bottom of the heater via four 3/0 welding cable wired in parallel. Current was carried from the positive lead of the power supply directly to the top of the heater rod via four 4/0 copper welding cables wired in parallel. Current was measured with a calibrated shunt provided by Ram Meter, model 22M, serial#SR0005420, 1200amp, 50mv. The voltage signal output of the shunt was measured with a calibrated Agilent 34401A multimeter and confirmed with the signal generated by the National Instruments DAQ to better than 1%

accuracy . Heater voltage for rod power calculations was measured at the upper and lower copper leads. This voltage was divided across two identical 4.62 k ohm resistors, with the resulting (half of full scale) voltage sent to the National Instruments DAQ. The actual voltage signal was measured with the same multimeter and confirmed with the signal generated by the National Instruments DAQ to better than 1% accu racy .

9

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041/A Pressure Measurements:

Two pressure sensors were used in this experiment. A calibrated Rosemount delta pressure transmitter, part number 3051SlCD4A2E12AlAMSQ4, serial number 0887364 was utilized to measure the pressure drop across the test section . Both pressure taps were placed in the throats of the reducing sections both prior to and after the test section.

The lines to both sides of this gauge were bled of air before experiments to result in a reading of zero when flow was stopped. A calibrated Rosemount pressure transmitter, part number 3051TG3A2B21AQ4MS, serial number 16114932 was utilized to measure the gauge pressure. This transmitte r was tied to the entrance pressure tap for the first two experiments, and tied to the exit pressure tap for the subsequent experiments. In both locations it was mounted in the same horizontal plane as the pressure tap it was connected to . The zero on this transmitter was verified when it was vented to ambient conditions . The range on the delta pressure transmitter wa s set to 10 psi Figure 23: Pressure Transducers [68 .9kPa], resulting in a calculated accuracy of+/- 0.11 psi[0.765kPa] . The range on the gauge pressure transmitter was set to SOpsig [345kPa], resulting in a calculated accuracy of +/-0.06psi [0.414kPa] .

Void Fraction Measurements:

Void fraction measurements were conducted at 11 distinct experimental conditions. To complete these measurements, 10 frames were chosen from available data to analyze. These frames we re not consecutive, but were chosen on basis of maximum image contrast between the background (rod) and the bubbles. The first step in the analysis was to determine the actual distance represented per image pixel, which was based on the 0.25" diameter heated rod and scaled images. Once th is 15a, d, e, f relationship was determined, the image was cropped to a large fraction of the rod diameter in width and approximately 4mm in height. Th is image file was then converted to an RGB type for recognition in lmageJ software . The recogn ition software was run on the image to recognize the edges of bubbles . Any not noted by the software were manually drawn in to the image. This edge data was then imported into an excel file and converted to volume based on the assumption of a circular/spherical bubble volume . This calculated volume of gas was then referenced to the volume of liquid in the analysis area .

Figure 24: Initial In addition to this analysis a bubble velocity was also calculated . This velocity calculation was Image accomplished by determining the number of con secutive images required for a bubble to traverse the imaged frame. This time was recorded for ten bubble traverses and averaged for the final result . 15a, d, e, f Void and velocity were only conducted on images with small bubbly flow at low heat flux.

Results of void fraction estimates along with images are presented on the fol lowing pages. For all examined conditions, the void fraction did not exceed - and in general were much lower.

Figure 25: The void fraction measurements followed logical trends except for the bottom to mid change on the Cropped Image nominal - run on 02/21/17 . It is assumed the error in our measurements were greater than the change in void fraction between those two conditions .

15a, d, e, f I Figure 26: Image with Edges 10

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Figure 27:115117 Figure 28: 115117 10:56 11 :16 Table A: Void Fraction Measurements, Early Experiments Date/Time 5a, d, I

1/5/17-10:56 e, f I

I 1/5/17-11:16 I

1/26/17-16:59 I

1/'30/17-10:56 2/9/17-11:32 Figure 31:115117 Figure 29: 1130117 Figure 30:219117 16:59 10:56 11:32 11

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Figure 32:2121117 Figure33:2/21/17 Figure 34:2121117 10:23 10:45 11 :08 Table B: Void Fraction Measurements, Later Experiments Date/TI me 02/21/17-10:23

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rimll I rt!'mnmmilmmnllll!!m~

. *Im

• I mm 02/21/17-10:45 02/21/17-11:08 02/21/17-11:46 02/21/17-11:35 02/21/17-11:27 Figure 35:2121117 Figure36:2/21/17 Figure 37:2121117 11 :46 11 :35 11 :27 12

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Experimental Operation:

Operation of the University of Wisconsin, Thermal Hydraulics Lab critical heat flux test rig involves a number of procedures that are outlined in more detail in Appendix 2. For the purpose of describing the ope ration for each individual test, an abbreviated operational procedure will be outline here:

1. Fill reservoir with deionized water to level slightly above test section return port

2. Energize glycol chiller for heat exchanger cooling

3. Turn on heat exchange pump to flow reservoir water through heat exchanger

4. Open pneumatic ball valves at the entrance and exit of the test section

5. Energize and adjust primary pump to flow water through test section at desired mass flow rate

6. Use regulator to pressurize system to desired pressure level

7. Turn on heater rod power supply

8. Adjust power supply output to achieve desired heat flux

9. Adjust glycol flow through heat exchanger to maintain desired inlet water temperature 2

10. Follow test matrix until CHF or maximum power output (9 .6MW/m ) is reached 13

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Test 1- Heater Rod 1 - 01/05/17 Target Conditions: T1n =-. =- P1n G =-

After initially pressurizing the system to ~ at the inlet to test section, the bulk water in the reservoir needed to be changed from room temperature (-20°C) to the target inlet temperature of 31.1°C. This was accomplished by flowing water through the test section at a mass flow rate of -

- and increasing the power to the heater rod to - -* Once the target in let temperature was reached, the glycol flow valve was partially opened to allow cold glycol from the roof mounted chiller to flow through the glycol-water heat exchanger. The glycol flow was adjusted until the heat removal matched the heat input from the heater rod indicated by a stable inlet temperature . At this point the power was increased to the heater rod until a heat flux of ~as reached. Concurrent to this power adjustment, the cooling was increased to maintain the desired in let temperature . Data was taken at these baseline conditions as wel l as variou s videos at select points in time. Once the baseline data and video was recorded, a critical heat flux run was completed .

The critical heat flux run was initiated at the baseline conditions of . The rod power level was increased every 30 seconds by increments of -i.2SkW until CHF was observed or the maximum power level was reached. As the power level was increased, the glycol flow was also increased to maintain the desired inlet temperature . The pressure and mass flow rate were monitored and adjusted as necessary. Automatic triggers were used to initiate the high speed cameras in orde r to capture the CHF event. The IDTI HS#-M -4 camera utilized a thermal trigger that was based off two thermocouples placed inside the heater rod at the expected location that CHF would occur, -i.3cm from the Figure 38: Failed Heater # 1 top of the heater rod . This thermal trigger wa s also used to shut down the heater rod power supply in an effort to save the heater rod from failure due to the CHF event. The Ametek Phantom camera was set to trigger off of either a flash of light which occurred at rod failure, or the same thermal trigger as the IDTI camera.

Test 1 achieved critical heat flux at - 3.34% higher than the estimated CHF of _

derived from the Groenveld LUT. Due to the unpredictable azmuthal location where CHF initiated, and the rapid nature of the CHF event, the power supply was not able to be shut down prior to the rod failing. Conditions at the highest heat flux prior to CHF as well as the conditions when CHF occur can be found in Table 1.

14

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Figure 39: High Speed Video Images, Testltl 15

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A

..,._ tnlitt Ttmp r6S h it T~mpl68

...... M~1 now. kg.k* 10

......, lnt e r~*TCO l

- In~ Pl~ ' kP.a ~I~

Figure 40: Data from Test#1, Stepped Power, Constant Inlet Temperature

...... M.1\~ftow, k8J.1. *10

........ i te rn~

• TCD I

- 1nt.tP1eu llP.1.atK Figure 41 : Data from CHF Event, Test#1 16

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A 2

Target Conditions: T;n 2

= =- =-

Test 2 - Heater Rod 2 - 01/11/17

~ P;n G Test 2 was run in an identical fashion as test 1, except that the mass flux was re duced to from 5000kg/m *s to 4250kg/m *s . This equated to a mass flow rate of 0.792kg/s. The test section was brought to the 2

target conditions with a base line heat flux of 3.4MW /m and data was taken as well as low and high speed video.

Once the baseline data and video was recorded, a critical heat flux run was completed .

The critical heat flux run was initiated at the basel ine conditions of . The rod power level was increased every 30 seconds by increments of ~i.2 SkW , as before, until CHF was observed or the maximum power level was reached . As the power level was increased the glycol flow was also increased to maintain the desired inlet temperature. The pressure and mass flow rate were monitored and adjusted as necessary. Test 2 achieved critical heat flux at

- 0.62% higherthan the estimated CHF of -

B 5a , d, e , f derived from the Groenveld LUT. As in test 1, the heater element failed before the power sup ply could be shut down . Conditions at the highest heat flux prior to CHF as well as the conditions when CHF occur can be found in Tab le 1.

Figure 42: Failed Rod #2 17

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Figure 43: High Speed Video, Test #2 18

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA 5a , d, e, f

..,_. M.a>>Ftow. 11&/i" IO

-.- 1n~1 l~mp #6)

Rod lnltl '66

_,._ Rod U i1Mi7

_..,._ LocilTtmp

• 6ll

...... ~~!'kl *

- ~Pr~u k.P~~

...... lnle rn.tl ITCDl Figure44: Data from Test #2, Constant Inlet Temperature, Stepped Power Figure 45: Data from CHF Event, Test #2 19

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Test 3 - Heater Rod 3- 01/28/17 TargetConditions:T001 =- - P001 =- G = -

Upon completion of test 2, it was determined that adjusting the local conditions for the CHF event to match the local conditions of General Atomics system's maximum heat flux was preferred. This translated to controlling the outlet conditions as opposed to inlet conditions . All subsequent testing was completed while controlling the outlet conditions. Significant sub coo ling was required to maintain the desired outlet temperatures, as well as a change in how the test was performed . Instead of increasing the heater rod power output every 30 seconds while matching the cooling level to maintain the inlet temperature, the inlet temperatures would need to be pre-calculated for each desired heat flux and the reservoir temperature set accordingly. As the heat flux increased, the inlet sub cooling also needed to be increased. Due to this change, all future tests would need to be operated as individua l constant heat flux runs, with heat flux increasing between runs, and inlet temperature lowered between runs . The test 3 matrix is shown in Figure 47. All future runs utilize the same progression in heat flux over 16 runs. Prior to test 3, but after test 2, the gauge pressure transducer was moved from the inlet of the test section to the exit of the test secti on .

After setting the system to a test section exit pressure of or test 3, the bulk water in the reservoir needed to be changed from room temperature (-20°C) to the target inlet temperature of

-

• This was accomplished by flowing water through the test section at a mass flow rate of -

- and increasing the power to the heater rod to ~ nee the target inlet temperature was reached, the glycol flow valve was partially opened to allow cold glycol from the roof mounted chiller to flow throug h the glycol-water heat exchanger. The glyco l flow was then adjusted until the heat removal matched the heat input from the heater rod indicated by a stable inlet temperature . At this point the power to the heater rod was dropped to 0 to allow the inlet temperature to drop -osc below the desired inlet temperature . At th is point the heater rod power was increased to a heat flux of - . The inlet temperature was then al lowed to increase until it reached a value -osc above the desired inlet temperature . At this point the heater power was shut down and the inlet temperature was allowed to cool until -osc below the desired inlet temperature for run number 2 in the test matrix. The outlet temperature was also monitored to make sure that the desired outlet temperature was crossed during the run. Each subsequent run was completed in the same manner. Cooling was increased as the heat flux increased to limit the ramp rate of inlet and outlet temperatures . In a typical run the inlet and outlet temperatures would increase - 1* cover -s minutes.

Test 3 did not achieve critical heat flux prior to reaching the maximum heat flux availab le of 9.6MW/m 2

• ~

This heat flux is 4.19% higher than the estimated CHF o f - derived from the Groeneveld (2007) LUT. ~

Conditions at the highest heat flux ach ieved fo r this run can be found in Table 1.

20

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Figure 46: High Speed Video Images, Test#3 21

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Figure 47: Experimental Matrix, Test #3 Figure48: Data from Experiment #3, Constant Exit Temperature

_.,_ M*lkff.. 1rcf1*to

_.._ trllrtl'kfflf'l(OJ Figure49: Data from Maximum Heat Flux Run 22

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA TargetConditions:T0 u1=- Pu1= - G=-

Test 4 - Heater Rod 3 - 01/30/17 0

Test 4 was conducted employing the same method as test 3. The test section exit pressure was adjusted to the mass flow was adjusted to and the inlet temperatures were ~

recalculated to achieve an outlet temperature of -

• Test 4 did not achieve critical heat flux prior to reaching ~

2 the maximum heat flux available of 9.6MW /m

• This heat flux is 11.3% higher than the estimated CHF of

- derived from the Groeneveld (2007) LUT. Conditions at the highest heat flux achieved for this run can be found in Table 1.

Figure50: High Speed Video Images, Test tl4 23

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Figure 51 : Experimental Matrix, Test #4

- - - "*it__.. ..

...... ......... lf>t,

_._....,,..,u*t

--l*l'"""'j*l,)lt Figure 52: Data from Test #4, Constant Exit Temperature Figure 53: Data from Maximum Heat Flux Run, Test #4 24

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A TargetConditions:T0 u=- Pout=- G=-

Test 5 - Heater Rod 3- 02/09/17 1

Test 5 was conducted employing the same method as test 3 and 4. The exit pressure was adjusted to 1 the mass flow was adjusted to -

- and the inlet temperatures were recalculated to ach ieve an outlet temperature of - . Test 5 achieved critical heat flux at - , 3.94%

higher than the estimated CHF of - derived from the Groenveld LUT. The power supply was not ab le to be shut down prior to the rod failing during the CHF event. CHF appears to have initiated -1cm down from the top of the rod burning a hole in the wall with the heater ultimately failing at the solder joint at the top of the rod . Conditions at the highest heat flux achieved prior to CHF as well as the conditions at which CHF occur can be found in Table 1.

Figure 54: Failed Rod

1. 3, After Test #5 Figure 55: High Speed Video Images, Test #5 25

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Figure56: Experimental Matrix, Test #5 Figure57: Data from Test #5, Constant Exit Temperature

- . - "lnlt1: Temp *6s*

Rod Inlet

• 66

- . - Aodh

• 6 7

-e-- fidt Temp

• 68

- HeM Hu1t.

- . - 1nt ern* I TCD2

- . - f l(tun*I Pre ts ltP* ebs I

Figure 58: Data from CHF Event, Test #5 26

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Test 6- Heater Rod 4 02/21/17 TargetConditions:T001 =- - P001 = - G= -

For test 6 the exit pressure was adjusted to -

the mass flow was adjusted to

, and the inlet temperatures we re recalculated to achi.eve an outlet temperatu re of B

5a , d, e, f

-

• Test 6 achieved critical heat flux at - 2.54% lower than the estimated CHF of - derived from the Groeneveld (2007) LUT. The power supp ly was not able to be shut down prior to the rod failing during the CHF event. Heate r rod 4 appears to have failed at the solder joint at the top of the rod . Conditions at the highest heat flux achieved prio r to CHF as well as the conditions at which CHF occu r can be found in Table 1.

Fiqure59: Failed Rod #4 After Test #6 Figure60: High Speed Video Images, Test #6 27

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Figure61 : Experimental Matrix, Test #6 Figure62: Data from Test #6, Constant Exit Temperature

_ _ ,_...,..,Q Figure63: Data from CHF Event, Test #6 28

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Test 7 - Heater Rod 5 - 02/23/17 TargetConditions:Tout= - - Pout= - G = -

For test 7 the exit pressure was adjusted to flow was adjusted to the mass and the inlet temperatures were B

5a d e f recalculated to achieve an outlet temperature o f -. Test 7 achieved critical ' ' '

heat flux at - 5.24% higher than the estimated CHF of -

derived from the Groeneveld (2007) LUT. Heater rod 5 is the first heater to survive a CHF event. A circular heat mark is clearly visible ~o . 6cm below the sold er joint at the top of the rod . Rod 5 will be used to rerun test 6-4 in an attempt to show repeatability in the tests . Conditions at the highest heat flux achieved prior to CHF as well as the conditions at which CHF occur can be found in Table 1.

Figure 64: Hot Spot on Rod #5 After Test #7 Figure65: High Speed Videos, Test #7 29

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041/A Figure66: Experimental Matrix, Test #7

.... , ..,...., .f"'

Figure67: Data from Test #7, Constant Exit Temperature

___. , ., * ._,. ., ,. ,,.

• l c::O c ..,..

- *<<.- *f'Wl' H.. UI Figure 68: Data from CHF Event, Test #7 30

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041/A Test 8 - Heater Rod 5 - 02/23/17 Target Conditions: - Pout= - G=- (Re-run of Test #6)

For test 8 the exit pressure was adjusted to was adjusted to the mass flow and the inlet temperatures were recalculated to achieve an outlet temperature of - . Test 8 achieved critical heat B

5a , d , e, f flux at - 0.62% lower than the estimated CHF of - derived from the Groeneveld (2007) LUT. The power supply was not able to be shut down prior to the rod failing during the CHF event. The heater failed in almost the exact location as the previous run at the same conditions as well as having CHF events within 1.5% of each other. The heat mark from the previous CHF run can be seen in the post test photos below. Conditions at the highest heat flux achieved prior to CHF as well as the conditions at which CHF occur can be found in Table 1.

Figure69: Failed Rod

1. 5 After Test #8 Figure70: High Speed Video, Test #8 31

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Figure71 : Experimental Matrix, Test #8 5a , d, e, f

""-" l - 1 Figure72: Data from Test #8, Constant Exit Temperature Figure 73: Data from CHF Event, Test #8 32

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Test 9- Heater Rod 6- 02/27 /17 Target Conditions: Tout= - - Pout= -

was adjusted to G =-

For test 9 the pressure was adjusted to the mass flow and the inlet temperatures were B

5a, d , e, f recalculated to achieve an outlet temperature of . Test 9 achieved critical heat flux at - 8.83% higher than the estimated CHF of

- derived from the Groeneveld (2007) LUT. The power supply wa s not able to be shut down prior to the rod fa iling during the CHF event. Heater rod 6 is the second heater to survive a CHF event. A circula r heat mark is clearly visible -i.ocm below the solder joint at the top of the rod . Conditions at the highest heat flux achieved prior to CHF as well as the conditions at which CHF occur can be found in Table 1.

Figure 74: Hot Spot on Rod #6, After Test #9 Figure75: High Speed Video, Test #9 33

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Figure 76: Experimental Matrix, Test #9

- ~" -*~* t o

(*II '""""*M Figure77: Data from Test #9, Constant Exit Temperature

-.. "°"L""l"I

- L~ 1-!il*WJ

..,.._ lJti,,,"""'*1~'""

WUt!ltUI 1(0 1 Figure 78: Data from CHF Event, Test #9 34

0

+

(')"

Table 1: CHF Testing Results Q)

Actual Estimated I

+/- +/- +/- DP test +/- Rod Date Test#- Tin Rod#

Error T,.. Stdev Error section Pow Stdev %

[kw) Error Stdev Error CHF %Difference (Act-Est)/Act

-c CD Q) 11 x

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i 27/2017 est 1-1 and 2-2 were ran with pressure and temperature being controlled at the entrance of the test section. All subsequent tests were completed controlling exit pressure and exit temperature.

CHFnot observed up to maximumheat flux of 9.6MW/m'2 Rerun ofTest #6 - Rod #4 Oji 0-

0 d Resistance= 0.05930 CD co (I) w 2 ......

d Surface Area =0.008977m c: 0

.i::..

=0.01032 m ~ (;;' .i::..

2 w Area =1.863*10..i m (Area of inner fl ow tube - Areaof heater rod)

"'§'*

CQ

o 0

0 0 imated CHF derived from Groenveld LUT [Groeneveld, et al, 2006) (!) 0

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Green highlighted ce lls indicate conditions at highest heat flux prior to reaching CHF for each test - Data averaged over 30 seconds "'c~ ......

Red highlighted cells indicate conditions at which CHFoccurred for each test - Data averaged over lOseconds if available --

)>

w

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041/A The table above summarizes the results of the CHF testing requested by General Atomics. A heating rod was custom designed for this series of experiments and six were fabricated and used . Eight distinct conditions were tested and one condition was repeated (tests 6 & 8). Tests 3 and 4 reached the limit of the power supply (9 .6Mw.m"2) before CHF occurred . Due to the local nature of the temperature sensing and the high heat flux involved, the rods, were in general, not re-usable after a CHF event. The first two tests were conducted with constant inlet conditions . These two were operated with a continuously ramped heat flux until CHF, with inlet conditi ons being held constant. The remainder of the tests were conducted with constant exit conditions. This involved pre-calculating inlet conditions for a given heat flux, setting the temperatures and pressures accordingly, and operating at a uniform heat flux for approximately 5 minutes. If CHF did not occur, conditions were pre-set for the next higher heat flux (generally steps of 200kw/m"2) and this power level was run . This process was continued until either CHF or the limit of the power supply (9 .6Mw/m"2) was reached .

Table #1 summarizes the resu lts of this critical heat flux testing. The table is chronologically ordered to maintain clarity in data retrieval. The first column is the date of the run. The second column is the test number followed by the rod number used in the test. The third column, T;n (inlet water temperature), is the reading from the lower inlet thermocouple followed by the standard deviation for this measurement, followed by the error in this measurement. Agreement between the lower inlet thermocouple and the thermocouple located near the bottom of the rod was very good .

The sixth column, Tout (exit water temperature), is the reading from the upper exit thermocouple, followed by the standard deviation of this measurement, followed by the error in this measurement. There was some discrepancy between the upper exit thermocouple and lower exit thermocoup le. It is surmised this was caused by the flow not being mixed upstream of the rod before interaction with the lower exit thermocouple. An energy balance was performed with the input power, mass flow, inlet temperature, and exit temperature based on the uppe r exit thermocouple . The table below rep orts the results .

Table 1: Energy balance from CHF (or Maximum) Runs

1. DataPolnts ~

10~

u 1040 1394 1496 3

108 72 The ninth column, " Pout", is the corrected reading from the gauge pressure transmitter, followed by the stan dard deviation of this reading, followed by the accuracy of this reading . For the first two runs, this was connected to and located level with the entrance pressure tap . The vertical distance between the pressure taps was 24.97" (63.4cm) . For the remaining runs this pressure transmitter was connected to and located level with the exit pressure tap .

The twelfth column , " DP test section", is the reading from the delta pressure transmitter, followed by the standard deviation of this reading, followed by the accuracy of this reading. The high side 36

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A of this gauge was connected to the lower pressure tap, while the low side of the gauge was connected to the upper pressure tap . This transmitter and the lines to it were bled of air before starting the experiment, to result in a zero reading at zero test section flow . Thi s measurement was used to calculate the exit pressu re for the first two tests (where gauge transmitter was located at lower pressure tap) .

The fifteenth column, " mass flux", is the mass flow rate generated by the Coriolis flow meter divided by the flow area, followed by the standard deviation of this measurement, followed by the error in this measurement. The accuracies of the flow meter and flow area were considered to attain the proper error values .

The eighteenth column, "rod pow", is the power supplied to the rod, followed by the standard deviation of this measurement, followed by the error in this measurement. Voltage and amperage measurement accuracies were considered to attain the proper error values .

The twenty first column, "actual heat flux", is the heat flux applied to the rod, followed by the standard deviation of this measurement, followed by the error in this measurement. Rod power and heated surface area accuracies were considered to attain the proper error values . Note that the values of the "actual heat flux" highlighted in maroon, are the heat flux values at which CHF occurred .

The twenty fourth column, "Estimated CHF", is the value at which CHF is predicted by Groeneveld et al. (2007) LUT to occur at the testing conditions, followed by the error in this measurement. This error was calculated by offsetting flow rate, heat flux, and fluid qualities (due to temperature errors) in both directions, by the maximum error, to both maximize and minimize predicted CHF . All predictions were done in F-Chart Software, Engineering Equation Solver, via the integrated "CHF Local" look-up tables. These tables are based on Groeneveld et al. (2007)

LUT and utilize the suggested diameter correction .

The last column,"% difference", is the difference between predicted and actual CHF values. Note the maroon shaded rows are where CHF actually occurred . This valu e was attained by the equation : lOO*(Actual CHF-Estimated CHF) I (Actual CHF) . It is fe lt this value represents the agreement between this testing and the Groeneveld et al. (2007) LUT.

Examples of the error calculations are included in appendix three . The base and processed data will be provided to General Atomics, via a hard drive, due to the size of the video files.

37

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Discussion:

Eight distinct conditions were tested for CHF values. One condition was repeated. Exit temperatures at C-=--:l CHF varied between - to * . Mass flux at CHF was varied between - and . Exit ~

pressures at CHF varied from . to - abs. Optical imaging at various frequencies was acquired throughout the testing .

At all of these test conditions, as noted in the last column of our table, there is reasonable agreement between the testing performed and the 2007 Groeneveld et al. LUT prediction . For all tested conditions, the CHF predictions were well within ten percent of the actual CHF. The repeated test (conducted with a different heater rod) resulted in a CHF value that was within two percent of the original test.

The optical imaging with the Ametek Phantom camera framing at 12,696 frames per second revealed some interesting phenomena . From these video files it is obvious the vapor generation is not uniform with time (there is some oscillation of the vapor generation at high heat flux at conditions below CHF) . There are obvious times of maximum vapor present, and obvious times of minimum vapor present. The frequency of the oscillation between the two states was investigated and did not seem to be uniform. It also did not seem to be necessarily sinusoidal, as the peak generation time was often present for longer than adjacent periods.

Quality imaging of the actual CHF event was difficult. One camera was available with the capability to frame with enough speed to produce a quality image. This camera position dictated what side of the rod was imaged . The CHF event azimuthal initiation point seemed to be random, and if the camera was not in the correct position (the location where CHF initiated), it was difficult to see the event. Another issue was that the intensity of the light that was produced during CHF typically saturated the camera . . Even with this limitation, some very interesting high speed videos were acquired that show the existence of the vapor bubble at the initiation point and a hot spot on the rod beneath the vapor bubble .

Rod failure at CHF was a major issue . Two thermocouples were placed in the rod to measure wall temperature . If the CHF did not initiate at the azimuthal and axial location of one of these thermocouples, the wall of the rod would melt before CHF could be detected and the power shut down . Even if the CHF initiated near one of these thermocouples, the rod was discolored (at the least) in a somewhat ci rcular area where the CHF had occurred . At these high heat flux levels, preserving a heater rod after a CHF event was difficult, or a matter of chance .

Several modeling procedures were attempted and the TRACE code was used to try to predict the CHF . It was however found that this code uses the 1997 LUT and resulted in significant under prediction of the CHF. This is discussed in detail in appendix 1. Predictions with the 2007 Groeneveld LUT however were found to be quite accurate and in all cases predicted the CHF within 10%. Under two sets of conditions we were unable to reach CHF even at a value that was larger than 10% higher than predicted .

38

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Appendix 1: Trace Code 39

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 /A GENERAL ATOMIC TRACE CRITICAL HEAT FLUX ANALYSIS Juliana Pacheco Duarte February 28, 2017 TRACE Overview The TRAC/RELAP Advanced Computational Engine (TRACE - formerly called TRAC-M) is the latest in a series of advanced, best-estimate reactor systems codes developed by the U.S .

Nuclear Regulatory Commission for analyzing transient and steady-state neutronic-thermal-hydraulic behavior in light water reactors. It is the product of a long-term effort to combine the capabilities of the NRC ' s four main systems codes (TRAC-P, TRAC-B, RELAP5 and RAMONA) into one modernized computational tool.

TRACE has been designed to perform best-estimate analyses of loss-of-coolant accidents (LOCAs), operational transients, and other accident scenarios in pressurized light-water reactors (PWRs) and boiling light-water reactors (BWRs). It can also model phenomena occurring in experimental facilities designed to simulate transients in reactor systems. Models used include multidimensional two-phase flow , non-equilibrium thermo-dynamics, generalized heat transfer, reflood, level tracking, and reactor kinetics.

TRACE takes a component-based approach to modeling a reactor system. Each physical piece of equipment in a flow loop can be represented as some type of component, and each component can be further nodalized into some number of physical volumes (also called cells) over which the fluid, conduction, and kinetics equations are averaged. The number of reactor components in the problem and the manner in which they are coupled is arbitrary. Reactor hydraulic components in TRACE include PIPEs, PLENUMs, PRIZERs (pressurizers), CHANs (BWR fuel channels),

PUMPs, JETPs Uet pumps), SEPDs (separators), TEEs, TURBs (turbines), HEATRs (feed water heaters), CONTANs (containment), VALVEs, and VESSELs (with associated internals).

HTSTR (heat structure) and REPEAT-HTSTR components modeling fuel elements or heated walls in the reactor system are available to compute two-dimensional conduction and surface-convection heat transfer in Cartesian or cylindrical geometries. POWER components are available as a means for delivering energy to the fluid via the HTSTR or hydraulic component walls. FLPOWER (fluid power) components are capable of delivering energy directly to the fluid (such as might happen in waste transmutation facilities) . RADENC (radiation enclosures) components may be used to simulate radiation heat transfer between multiple arbitrary surfaces.

FILL and BREAK components are used to apply the desired coolant-flow and pressure boundary conditions, respectively, in the reactor system to perform steady-state and transient calculations.

40

Attachment 1O Critical Heat Flux Testi ng at the University of Wisconsi n Final Report 3044 1 R00041 I A EXTERIOR components are available to facilitate the development of input models designed to exploit TRACE's parallel execution features.

TRACE CHF Correlations The point where the maximum heat flux occurs in the idealized boiling curve shown is denoted as the CHF point, (q" CHF , T CHF), and is characterized by both the critical heat flux and the wall temperature at which it occurs. This is the point where the heat transfer regime transitions from that where the liquid phase wets the wall (i.e., nucleate boiling), to the post-CHF regimes where liquid-wall contact is either transient (transition boiling) or non-existent (film boiling).

In TRACE, the role of the CHF model is two-fold:

1) Determine the transition point for the heat transfer regime, and

2) Serve as an anchor point for the transition boiling wall heat flux.

To serve both these roles, the CHF model in TRACE must provide a continuous estimate of the CHF over a wide range of conditions with reasonable but conservative accuracy. This range of conditions must extend from the high pressure, high-flow conditions typical of operating PWRs and BWRs, to the low pressure, low-flow conditions.

For the analysis of anticipated transients, such as a perturbation in the core flow or inlet sub cooling, the metric is the departure from nucleate boiling (DNB) margin. DNB is one of the types of CHF and for each fuel type there are specific DNB correlations with high accuracy.

Most of these correlations employ the boiling length concept, in which the core inlet quality or enthalpy explicitly appears in the correlation. During many transients and postulated accidents, however, the use of boiling length correlations is not appropriate. For example, during a cold-leg-break LOCA, the core experiences a flow reversal thereby rendering the definition of the core inlet ambiguous. In addition, these correlations are unsuited for general use in TRACE because they are highly empirical with a limited range of validity, and are unreliable when extrapolated outside their original database.

Therefore, for the default CHF model in TRACE the 1995 AECL-IPPE CHF look-up table [2]

was selected. It is based on an extensive database of CHF values obtained in tubes with a vertical up flow of a steam-water mixture and provides the value of the critical heat flux as a function of the local conditions. As described below, a correction factor is included to improve the accuracy of this table when applied to rod bundles. This look-up table allows for a reasonable predictions of CHF based on the local flow conditions for a wider range of conditions than would be possible with either empirical correlations or phenomena based models.

The method of determining the value of the critical heat flux was selected for TRACE because of its reasonable accuracy and wide range of applicability. The AECL-LUT CHF table is based upon an extensive database of CHF values obtained in tubes for a vertical upward flow of a steam-water mixture. While the database covers a wide range of flow conditions, the look-up 41

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A table was designed to provide CHF values for 8 mm tubes at discrete values of pressure, mass flux, and quality.

TRACE Analysis of GA Subcooled CHF Experiments The TRACE model for the annular test section was developed based on the test facility specifications, input conditions, and the simulation method as discussed in Appendix A. The current simulations use the hydraulic diameter for the characteristic length in the heated transfer calculations. The hydraulic diameter for the annular flow channel is found to be equal to the outer channel diameter minus the inner channel diameter; i.e., 10.31 mm. This is used in the simulation as well as in the K 1 diameter conection term instead of the recommended heated diameter. The reason for this choice is based on our analysis of the TRACE user guidelines and the determination that the recommended use of the heated diameter for the conection factor in the CHF look-up table [2, 3] is inappropriate. The use of the conventional heated diameter (defined as four times the flow area divided by the heated perimeter) underestimates the critical heat flux and, as suggested by Ref. [3], the hydraulic diameter should be used (see Appendix B for details)

CHF = CHFTABLE x K, (1)

The TRACE results using the 1995 Look-up Table [2] are shown below. More recent CHF data for highly subcooled conditions are only incorporated into later data sets not used in TRACE [3].

This seems to be the only reason that TRACE underestimates the experimental observed CHF point.

Inlet Temp.

oc 30 ......

Mass flux kg/m2 -s Local quality CHF MW/m2 30 40 40 .. - ** B References

1. USNRC, TRACE VS .840 THEORY MANUAL, Field Equations, Solution Methods, and Physical Models, Dec. 2014.

2. Groeneveld, D. C., et al , "The 1995 look-up table for critical heat flux in tubes", Nuclear Engineering and Design, 163, 1-23, 1996.

3. Groeneveld, D. C., et al., "The 2006 CHF look-up table", Nuclear Engineering and Design, 237, ppl90-1922, 2007.

42

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Appendix A - Test Facility Specs, TRACE Input Parameters and Simulation Method Table A.1 - Test section parameters Parameter Value Units Channel outer diameter 16.66 mm Cladding tube OD/Channel ID 6.35 mm Cladding wall thickness 0.51 mm Cladding material IN-625 2

Nominal heat flux MW/m Heated length m B

Inlet temperature Inlet pressure Minimum mass flux Nominal mass flux

....* oc kPa kg/m 2-s kg/m2-s Table A.2 - TRACE input parameters Parameter Value Units Hydraulic diameter 10.31 mm Heat diameter (assumed) 10.31 mm Flow area 186.32 mm2 Minimum mass flow Maximum mass flow Outlet pressure

--* kg/s kg/s kPa B Maximum time step 0.01 sec Minimum time step 10*12 sec The TRACE input model and associated boundary conditions are shown in Figure A.1 . Flow channel length is equal to 558.3 mm divided in sixty uniform mesh size and the heated length started at 56.6 mm. The heated length has a structured mesh that is uniformly divided in 45 nodes. A power component for the heated structure, not shown in the figure , is used to uniformly 43

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA heat the clad with thickness 0.51 mm and inner of the heated cylinder is filled with Boron Nitride. The IN-625 properties were included as a user-defined material from GA information.

10 - HEAT STRUCTURE (simulates the heated rod) 60 - PIPE (simulates the flow channel) 10 70 - BREAK (pressure boundary condition) 80 - FILL (inlet mass flow and temperature boundary conditions)

Figure A. l - TRACE model and boundary conditions.

The onset of CHF was determined by increasing the total power by 1kW at each 50 seconds as it was assumed to occur during the experiment operation. The temperatures of the wall at the end of the heated length (tsurf-10A44), the liquid (tln-60A50) and the local heat flux (qppo-10A44) are shown in Fig. A.2 for the nominal mass flux and at the higher inlet temperature condition.

44

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A

- tsurfo- 10A44

- tln-60ASO

- tsat-60ASO

- qppo- 10A44

- qchfo- IOA44 0 50 100 150 200 250 100 150 200 250 300 Time(s) Time (s)

Figure A.2 - CHF fo r the nominal mass flu x and 40 °C inlet temperature.

45

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Appendix B Hydraulic and heated equivalent diameters in heat transfer correlations Summary Hydraulic and heated equivalent diameter are approximations to take into account different geometries in thennal-hydraulic analysis. These concepts can be misinterpreted and they are discussed here based on well-known heat transfer correlations.

Nomenclature A- Flow area Pw- wetted perimeter P he - heated perimeter D hy - hydraulic equivalent diameter D he - heated equivalent diameter D 0 - outer diameter in an annular geometry D; - inner diameter in an annular geometry D e - equivalent diameter D - rod diameter P - pitch cP - specific heat G - mass flux m - viscosity k - thermal conductivity h - heat transfer coefficient Nu - Nusselt number Re - Reynolds number L - square channel width N - number of rods in a bundle Introduction The hydraulic and heated equivalent diameters are widely used in friction and heat transfer coefficients in nuclear thermal-hydraulic calculations. Most of the correlations used in nuclear reactor systems codes (e.g. TRACE, RELAP, MELCOR, etc.) and sub channel codes (e.g. COBRA, VIPRE, etc.) are empirical correlations or phenomenological models based on data collected in heated tubes. To apply these correlations to different geometries, such as annular channels and rod bundles, the concept of equivalent diameters is used. Although it is simple in concept, it is very common to mistake them and a more careful attention is required in this context.

46

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Discussion The hydraulic diameter is well defined and explained in many engineering textbooks (e.g., Kazimi and Todreas, 2012 & El-Wakil 1978) as a value equivalent to the round tube diam eter, i.e. , four times the flow area divided by the wetted perimeter, Eq. (1), where the wetted perimeter is defined as the sum of all perimeters in contact with the fluid.

(1)

Eq. (1) is, in general, accepted and used in most friction factor correlations for internal flow . Note that, for a pipe geometry, the hydraulic diameter is the diameter of the pipe. For a square rod bundle with width L and N rods of radius R, the hydraulic diameter is 2

L2 -N(nR )

D =4--~~ (2) h.v 4L + N (2nR)

The misunderstanding arises when heat transfer correlations are used. Kazimi and Todreas (2012) , and El-W akil ( 1978) suggest to use the hydraulic diameter as the characteristic length for heat transfer correlations for geometries other than circular, which is in agreement with Weisman (1959) correlation.

Weisman (1959) correlation is a we11-known correlation based on square and triangular lattice rod bundles where the Nusselt and Reynolds numbers are evaluated using an equivalent diameter equal to the hydraulic diameter, Eq. (3). The fluid properties are evaluated at the film temperature except cP.

(Dµ aJ (c J' 08 13

-hD- - c hy -

-- hy

• -pµ

- (3) k k where C = 0.026(P I D )-0.006 for 1.1:'.S:P I D:'.S:1 .5 (triangular pitch lattices)

C = 0.042(P I D )-0.024 for 1.1:'.S:P I D:'.S:1.3 (square pitch lattices)

A more recent correlation for square lattices (El-Genk et al , 1993) uses the heated equivalent diameter to evaluate the dimensionless coefficients and the mean bulk temperature for water properties. Dingee et al (1955) also use the heated equivalent diameter to evaluate the dimensionless numbers for the heat transfer calculation in rod bundles of different geometries. The authors ca11 the heated diameter as an infinite array diameter reasoning that for heat transfer calculation the effected of the non-heated wall can be disregarded . The heated diameter is defined as four times the heated area divided by the heated perimeter, Eq. (4).

(4)

Again, for a heated tube, the heated diameter is equal to diameter of the tube. For a square rod bundle with N heated rods, the heated diameter is given by 47

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A L2-N(7rR 2)

D = 4-----'---'- (5) he N(2trR) which it is greater than the hydraulic diameter.

Kim and Li (1988) shows a semi-analytical solution for infinity square arrays and the Nusselt number in laminar flow evaluated using both the hydraulic and the heated perimeter. The results are plotted in Figure 1, where constant properties were assumed.

15 Q)

.D E

~ 10 Q5 I/)

I/)

J z

5 1.0 1.33 1.5 2.0 2.5 P/D Figure 1 - Semi-analytical solution for laminar flow along circular rods (Kim and Li, 1988).

It is worth noting that Weisman (1959) and El-Genk et al (1993) correlations predicts closer results when they are evaluated using the same characteristic length as shown in Figure 2 (for G = 1000 kg/m2s, water properties at 15.5 MPa and 310 °C, and L = N xP).

48

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA 800

• Weisman (1 959)- Ohr

• Weisman (1959)- Dhe

.t. El-Genk et al (1993) - Dhy

.... 600 Ci>

• El-Genk et al (1993)- D11e

.0

• E

J **

-c:

Qi I/)

400 z

I/)

J

• 200

• I I

I I

1 0

1.0 1.1 1.2 1.3 1.4 1.5 PIO N

- .:it:.

E I

Weisman (1959) -

Weisman (1959) -

D hy Dhe El-Genk et al ( 1993) - D hy 25

~ *

--.:it:.

c

"' El-Genk et al (1993) -

D he Q)

• o I 20

!E

• Q)

~

0 u

L..

I/)

15

"' "' "'* I * * "' "'

c

--ro L..

ro Q)

c 10 I I I I I 1.0 1.1 1.2 1.3 1.4 1.5 P/D Figure 2 - Comparison of turbulent single-phase heat transfer coefficient evaluated using the hydraulic and the heated diameters in a square bundle.

For annular flow geometry internal heated, it seems like the hydraulic di ameter is more commonly accepted as the characteristic length for heat transfer calculations. McAdams et al ( 1949) studied the heat transfer from an electrically heated element to water flowing in annular channel. The equivalent diameter in this case, simplifies to (6)

For critical heat flux (CHF) prediction, a widely used method is the look-up tables developed by Groeneveld et al (1986, 1989, 1999, 2007). The CHF experiments were perfonned in heated tubes for a 49

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsi n Final Report 3044 1 R00041 IA broadly range of pressure, mass flow and local qualities, and normalized to an 8 mm tube. The effect of the tube diameter is taken into account by a correction factor (7)

The first papers (Groeneveld 1986; 1989) suggest the heated diameter as correction factor while a more recent one (Groeneveld, 1999) suggest the hydraulic equivalent diameter is more appropriate.

For annular geometry the hydraulic and heated diameter can be significantly different. For example, the experiment #95 from Barnett (1966), the rod dimeter is equal to 0.375 in (9.53 mm) and the surround unheated tube 0.875 in (22 .2 mm) giving D he = 42.3 mm and Dhy = 12.3. Using Eq. (7) and the more recent CHF look-up table (Groeneveld, 2007), the predicted CHF is equal to 3348 kW/m 2 (12% higher than the experimental data presented by Barnett, 1966). However, when the heated diameter is used , the K 1 factor is equal to its minimum value of 0.57, which reduces the predicted CHF to 2405 kW/m 2

• For a rod bundle geometry, the different between hydraulic and heated diameters may not be as large as for annuli. In both cases, however, the hydraulic diameter should be used , in the lack of experimental data, as indicated by Groeneveld (1999).

Conclusion The hydraulic and heated equivalent diameters are approximations used to translate more complex flow geometries into equivalent circular tube geometries. The diameters should not be used interchangeable but accordingly with the suggestion by whomever developed the correlation in the case where no experimental data is available. Although the definitions are not always clear, it is a general assumption to assume the heated diameter for rod bundle geometries and the hydraulic diameter for annular geometries as the appropriate characteristic length in heat transfer calculation. In the case of the Look-up table for critical heat flux developed by Groeneveld et al (2007), the author (Groeneveld et al, 1999) explicitly suggest a correction factor based on the hydraulic diameter and, therefore, the use of the heated diameter underestimates the critical heat flux.

References Barnett, P. D., "A correlation of burnout data for uniformly heated annuli and its use for predicting burnout in uniformly heated rod bundles", AEEW-R 463, 1966.

Dingee, D. A. , Bell , W. B. , Chastain, J. W. , and Fawcett, S. L., " Heat transfer from parallel rods in axial flow' ', Battelle Memorial Institute, Report BMI-1026, 1955.

El-Genk, M. S., Su, b., and Guo, z., "Experimental Studies of Forced, Combined and Natural Convection of Water in Vertical Nine-Rod Bundles with a Square Lattice," Int. J. Heat Mass Transfer, 36, 2359-2374, 1993.

Groeneveld, D. C., Cheng, S. C., and Doan, T. , "1986 AECL-UO Critical Heat Flux Lookup Table," Heat Trans. Eng., 7, 46-62, 1986.

Groeneveld, D. C., et al , "Computation of single- and two-phase heat transfer rates suitable for water-cooled tubes and sub channels", Nuclear Engineering and Design, 144, 61-77, 1989 Groeneveld, D. C., et al , "The 2006 CHF look-up table", Nuclear Engineering and Design, 237, 1909-1922, 2007 .

50

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Groeneveld, D. C., et al., "A General Method of Predicting Critical Heat Flux in Advanced Water-Cooled Reactors," Proceedings of the 9th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-9), San Francisco, California, October 1999 Kim, J.H. , and Li, W.-H., "Heat Transfer in Laminar Flow Along Circular Rods in Infinite Square Arrays," J. Heat Transfer, 110, 252-257, 1988.

McAdams, W. H., et al. , "Heat Transfer at High Rates to Water with Surface Boiling," Ind. Eng. Chem .,

41 , 1945-1955, 1949.

Weisman, J. , "Heat Transfer to Water Flowing Parallel to Tube Bundles," Nuclear Science and Engineering, 6, 78-79, 1959.

51

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041/A Appendix 2: Operational Procedure 52

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A OPERATIONAL PROCEDURE

1. Turn on computer and open labview program controlling experiment

2. Turn on VFD's controlling primary and heat exchanger pumps

3. Visual check that all instrumentation is working properly

a. TC's, Pressure, Flow meters, etc.

4. Fill reservoir with deion ized water to level slightly above test section return port

a. Open ball va lve at water storage tank

b. Open ball valve at test rig inlet

c. Open ba ll valve at primary pump outlet (water can now flow to test loop)

d. Turn on primary pump to fill reservoir to desired level - pump flow >0.5kg/s

e. Close ball valve at test rig inlet and water storage tank

5. Energize glycol chiller for heat exchanger cooling

a. Ensure that chiller pump starts and VFD is outputting 40Hz

6. Turn on heat exchange pump to flow reservoir water through heat exchanger, adjust pump speed to achieve a flow rate of ~5 0GPM

7. Open return side cooling valve (va lve is for wate r returning from the reservoir), leave sup ply side closed

8. Open pneumatic ball valves at the entrance and exit of the test section

9. Energize and adjust primary pump to achieve a flow rate of -1kg/s through test section and let run for a minimum of 5 minutes in order to remove any air entrained w ithin the system

10. Adjust regulator to pressurize system to desired pressure level

11. Bleed air from the high pressure and low pressure sides of the differential pressure transducer

12. Zero coriolis flow meter

a. Shut off primary pump, allow system flow to stabilize

b. Close pneumatic ball valves

c. Utilize flow meter transmitter to zero flow meter

i. Enter Setup mode ii. Enter Calibration mode iii . Enter Flow Zero mode iv. Push "O" to calibrate flow meter

v. Accept calibration - write down zero value vi . Return to Measu re mode

d. Open pneumatic ball valves

13. Energize and adjust primary pump to achieve flow rate for desired testing conditions

14. Prepare to turn on main power supply

a. Turn on power su pply disconnect switch

b. Check labview to verify that the power level is set to 0

c. Check controller to verify that no signal is present

d. If 0 voltage present, turn on power supply at power supply main controller panel

e. Power supply can now be operated from labview control screen

15. Increase power level in labview to reach desired rod power, (-20-30kW), for preheating water in reservoir to desired te sting conditions

16. While waiting for reservoir to reach temperature

a. Setup lights to ill uminate test section 53

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A

b. Setup high speed cameras and SLR camera

c. Verify that thermal trigger and optical trigger are functioning

17. Once the desired reservoir temperature is reached verify that the mass flow and pressure are also within specifications, adjust if needed

18. Adjust glycol flow through heat exchanger to maintain desired inlet water temperature by partially opening (1 full turn to start) the supply side cooling valve

19. Once inlet temperature stabilizes slowly lower heater rod power level to zero

20. Allow inlet temperature to drop 0.5°C below

21. Increase power level to reach desired heat flux according to test matrix

a. Increase data collection to 0.1 seconds while heating

22. Adjust glycol flow through heat exchanger to limit the temperature increase to less than 1°C/5minutes

23. Allow inlet temperature to rise 0.5°C above desired inlet temperature

24. Slowly lower heater rod power level to zero

a. Decrease data collection to 1 second while cooling

25. Allow inlet temperature to drop 0.5°C below desired inlet temperature according to the test matrix

26. Repeat steps 21-25 unti l all runs within the test matrix are completed or a CHF event has occurred 54

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Appendix 3: Sample Error Calculations 55

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A

Example Error Calculations T;n Error Calculation Example Error+/- =Tin+/- 1.1*

• Special Limits of Error for K-Type Thermocouples Tout Error Calculation Example Error+/- =Tout+/-1.1*

• Special Limits of Error for K-Type Thermocouples Pout Error Calculation Example Error+/- =(Pout+/- 0.414**)

• • Calculated from Reference Accuracy Equations from manufacturer

+/- (0.0075* ([URL/Span]) % of Span URL = 800 psi Span = 50 psi 0.06psi = 0.414kPa DP Error Calculation Example Error +/- = (DP +/ - 0.076**)

• • Calculated from Reference Accuracy Equations from manufacturer

+/ - (0.005+0.0035* ([URL/Span])% of Span URL= 300 psi Span = 10 psi 0.0llpsi = 0.076kPa Mass Flux Error Calculation Example Error+/- = Mass Flux+/- Accuracy ***

• • • Calculat ed from Accuracy Equation from Manufacturer

+/ - 0.10% + ((Zero Instability/Mass Flow Rate)

• 100)% of mass flow Zero Instab ili ty = 7.56666* 1011 -5 kg/s 56

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041/A Example error calculations for Heat Flux, Mass Flux, and Rod Power calculated using EES software F'do:C:\Users TH De top\GA error ~ations .EE S 3/&'2017 I :36:55 PM Pago 1 EES Ver. 0.203. 1100 FOi' use only by Studonts and Faculty, Colloge of Engineenng U!Vversi1y of Visoonsm . Madison L_error*sm*****

t; 17 .85" conven(ln,ml d_~0.25029 d_l_error**

. .*con ven 111

..ifm*.m l i)ll d_0=.6S6"conv d_o_error..1

. ert. 1!Ull.m l*

1 l *

~&itS'4*; . 0"2--0 i"2) m dot error.ft.£1\

Voll=sJ.30607 volt error.om AmP,.111 5.009 Amp_error.. 0.01 power=VO amp H_a.. L"d_i" pi#

h_fklx=power/h_a mass_fll><=m_dotlflow_a Pa'1ial derivatlvo  % of uncenaintY I Amp

• 7433 37 .SS Cl'.

I d *

• 1 304E~OO 6.00 o/.

J1W/ildo .. 0 O.OO o/.

ill /ill " -1.829E*07 18 89 o/.

1am.. .41eE. 10 o.oo er.

1avo11 = 123134 37 S6 o/.

()naSSb/il Amp = 0 o.oo cr.

(mJ ()naSS... / i)d,

• 265603 3.43 Cl'.

(m) <rnass.....,ildo " -6961 40 04.33 "*

[mJ i)'llassa.Jill

• 0 0.00 o/.

[k!>'s) ;rnass-..1am . S367 2.24 er.

Voll = 67.31+/--0.6731 M i)'llass 1ilVolt .. O o.oo cr.

or 1aA.rrfJ .. 67.3 S0.00 41'.

(m) if>ON91' f()d = 0 o.oo cr.

(m) if>ONor t do

• 0 o.oo cr.

[mJ or 1aL " o O.OO o/.

m= [ki>fsJ -;poNor tam= o O.OO o/.

Volt = 67.311-0.6731 M iJXNll!K 1aVo1t "' 1I 1S S0.00 o/.

57

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Appendix 4: Calibrations 58

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R0004 1IA 1/8" Thermocouples Fonn:053-0005-3 Rev.C Certificate Of Calibration for University of Wisconsin-Madison ust. P.O. #: GAIOIOJ6 Report #: OM-121123315 Test Item: KMQ316S -125U- 12-CAL-3 WO : s 00215380 Recal Date: Per System Application Ref. J.D.: WK140410-02 CAL-3 Omega Engineering, Inc. certifies that the above instrumentation has been calibrated and tesied lo meet or exceed the published speci fi cations. This calibration and testing was performed using instmmentatioo and standards that are traceabl 10 the Nationa l Institute of Stand ard and Techno logy. Calibration has been performed in compl iance with ISO 10012-1 , I 0 9001 and AN I/NC L Z540-l-1994 as well as ASTM E 230 and AN I MC96.J. This Certificat Report shall 001 be reprodu.c ed, except in full, Y.~lhout writtell consent of Omega Engineering Inc.

Test Conditions: Temperature 73 °F Relative Humidity 29%

Procedure used: QAP-2 100 The maximum calibration un enainty is calculaied to be 0.3C from -2SC 10 SOO and 0.55C from 500C to 11 OOC.

I STRUME TS USED:

~ ~ CAL P UE DATE N.I ST NVMBERS RTD (Bums) 745098 06129117 N PR-100-01 RTD (Donis) 16SS6S 06129/ 17 N PR- 100-05 RTD (Bums) 765566 06129/ 17 NNPR- 100-06 Agilent 34401A US36027293 041021 17 N DM-100-3 1 TRClll 1-0012 0 10/ 17 CL--098-31 DP2S I 2 193-022-2473 06129117 NNDP-100-10 Nom ina l Actual Test l odicuted Probe No.

Temper a ture Tempcralu re Temper ature I 2 12 Of 212.Q Of 2 11.7 °F I 392 °F 392.0 Of 393 .3 Of I 752 °r 752.0 Of 753.0 °F

~ JI Ai""'~.. j Metrology Technician Q ua lity As ur11nce In spector Ca libration Date: 1 0 16 P<lg l of 2 OMEGA Eng ineering, Inc., One Omega CitQe, P.O. Bo* 336. Bnd eport, NJ 08014*0336 Telephone: (856) 467-4200

• FAX: (856) 467* 1212 www.omega.com e-mail: lnfo@omega.com 59

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A 1/8" Thermocouples: continued

• 0 >1au. .....,,_ , _ <*M,..** Fonn:OSJ-0005-3 Jlev.C ontinued Report # OM- 1211 233 15 Nominal dual Test lndicaled Probe No.

T emperature Temperature T emperature 2 2 12 °F 212.0 *p 2 11.7 °F 2 392 °F 392.0 °F 393.3 °F 2 752 °F 752.0 *r 753 .1 °F P g 2 of 2 OMEGA En gineering, Inc., One Omega Circle, P.O. BoK 336. 6ridgepon, NJ 08014-0336 Telephone: (856) 487-4200

• FAX: (856) 467-1212 www.omega.com e-mall: /nfo@ome9a.com wa ""'"

60

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A 1/16" Thermocouples :

Form; 053-0001-3 Rev. E Certificate Of Calibration for University Of Wiscon in - Madison Cust. P.O.#: GA Report II: OM- 121123377 Test Hem: KMQ316 -062 -1 8- A 3P WO : s 00224992 Rccal Date: Per S stem Application Ref. l.D. : VK141013-07 CAL-4 Omega Engine ring, Inc. certifies that the abo e in tnunentation bas been calibrated and te ted to meet o r exceed the published specifications. This calibration and testing was perfonned using instrumentation and s1andards that are traceable to the N11tlonal Institute of Stand ard a nd Technology. alibration ha been performed in compliance with ISO 100 12-1 , ISO 9001 and A . l/NCSL Z540- l -1994 as well asASTM E 2 Oand ANSI MC96. I . This Certificate/Report shall not be reproduced, e cept in foll, without written consent of Omega Engineering Inc.

Test ondit ions: Temperature 72°F Relati ve Humidity 21 %

Procedure used: QAP-2100 The ma.,imum calibration uncerrainty is calcula1 d to be 0.3C !Tom -25C 10 500 C and 0.55 !Tom SOOC 10 11 OOC.

INSTRUMENTS IJ D :

.s.E.filA.L. CAL DUE DAT!i Agilent 34401A US36127770 0410 17 NNDM-1 00-32 01'251 3010-0 18-1409 12107/16 NDP-09X-02 DP2SI 1360-007-924 06101117 NNDP- 100-12 TRCll l s 06/ 1 !7 N 'CL-098- 19 RTD(Dums) 912379 0611 6117 PR-100-1 RTD (Rosemount) 5061 06/0 1117 PR-100-18 RTI:> (ASL) B448 07 06/29117 NPRB- 100-0 Pro be No. Nominal Actu al Test Indicated Temperature Temperature Tempe rature 0°C 0.00°C 0.60°C 99.83°C 299.74° Metro1ugy Techni cian It td<-~*-76 A ~* --~-

Quality Ass urance lnsp ctoT Calibratlon Date: 11/28/ 6 Page 1 2 OMEGA Engineering, Inc., One Omega Circle. P.O. Box 336. Bridgepon, NJ 08014-0336 Telephone: (856) 467-4200

• FAX: (856) 467-1212 www.omega.com e-mail: lnfo@omega.com 61

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA 1/16" Thermocouples : continued

• '" o.w:ca T_ ......,,,.. ,,..,,....,, Foml: 053.0001-3 Rev.

Conti.nucd Report # OM - 12 11 23 77 Probe No. Nomina l Actual T est Indicated Temper ature Temperature T empcrut ure 2 0°C 0.00°C 0.58° 2 100°c 100.00°c 99.82° 2 300°C 300.00° 299.65°'

---

*-- -- -- -------~ --- ---*----- -----*-**-*

Page 2 of2 OMEGA Engineering, Inc ~ One Omega Clrtlo, P.O. Box 336, Bridgeport, NJ 0801 4*0336 Telephone: (856) 467-4200

• FAX : (856) 467-1212 www.omega.com e-mail: lnfo@omega.com 62

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Shunt:

CERTIFICATE OF CALIBRATION UNIVERSITY OF WISCONSIN 1500 ENGINEERING DR MADISON, WI 53706 Model ' umb<r Serial Numbu u cripc.ion RAM METER 22M NIA 1200AMP 50MV Ctlibrarioo Du ~ Oare ....b upcrvi11o r 10/18117 TODDRUTILA ~~

R m M ter Num~1' Ambient Tanpcri1;t1PR RtlaliR Humidity Within SR-0005420 73°F 64%

~rt_ifi ~ don Ram Meter Inc. certifies that the Instrument listed above has been calibrated to the Manutacture~s specifications (tolerances). The calibration of our laboratory standards used In calibrating your Instrument Is traceable to the National lnstiMe of Standards and Technology or other national physical measures recognized as equivalent to NIST. The NIST numbers of traceability are listed below.

IST N*mb<r *)

2358200002 T FINAL READING: 0.000041650 2358200001 T 0120 11

• 2 ELR001 : 1340626375 Additiooa.I loform.a.tioo THE CALIBRATION SYSTEM TO CONTROL THE ACCURACY OF OUR MEASURING ANO TEST EQUIPMENT COMPLIES WITH MIL-ST0-45662A.

63

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Gauge Pressure Transmitter:

22 November, 2016 Emerson Procon Manegomont Rosemount Inc.

602 1 Innovation Blvd EMERSON. Shakopee, MN 55379 Callbratlon Data Shoot Conslstont with ISO 10474 3.1 or EN 10204 3.1 Customer Information Manufacturer Information Nam e : WISCONSIN u IVERSITY OF Salos Ordor: 4 74 66~

PO: CC-Ande!Son-09-Nov-16 Line: 2

-~-

Device Information Calibration Information Device Type : Pressure Tron...,* ter PDTag: Factory: SHAKOP E, M

• USA Station Name: SHAl<_INLINE_CALIBRATION_04 Sorlal No: 287 5322 Operator ID: 60525 Model No : 305 1 TG3A2 B2 1AQ*M~ Calibration Dato : 1112112016 t :53:26PM Module Serial No: 16 11 4932 Output: Llnoar Device ID: 16114932 1nterna1Re r

• 2oom14 llllmllll 1111 II IlllllDlllllllllll RlllHI Equipment Used le:>.oe3eQ ILOfd l!Ol! 17120!20 17 1!*35;00{\M

( p3.55 130 I PcMSUfe Contr'Qle!

Calibration Data Ra nge: 0.000 TO 800.000 PSI

'14 ol Rl "l!* AppKed Pres1ure Requested Applled Pre11ure Analog Output tmA )  % Span Error P1.1 11F1ll 100.000 ll00.000 PSI 800 0000 PSI 20.00010 O.OOOC3 PASS

[ 80 000 04 0.000 PSI 6'100000 PSI 18.79992

• D.00050 ""'SS I 80000 460 000 PSI '80 0000 PSI U .691188 -0.00076 ""'SS I CO 000 320.0CO PSI 3:20.0000 PSI t0,S9999 -0 .00012 ""'SS I 20.000 160.000 PSI 160.0000 PSI 7.2001 8 0.00113 Pl\SS

[ 0.000 0.000 PSI 0 0000 PSI 4.()()01

• o.oooes P"SS This is to certify that the listed product meets the applicable Rosemount Specifications.

Measuring and test equipment used in the manufacture and inspection of the listed product are traceable to the National Institute of Standards and Technology. The calibration system was designed to meet the intent of ANSI Z540- 1-1994 .

Kelly Klein Vice President of G lobal Quality, Approvals & EHS Page 1 of 1 JPG2875322_Q4-PRESSURE_RSK_ 1 64

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A DP Pressure Transmitter:

22 November, 2016 Emerson ProcoH Management Rosemount Inc.

• ' 602 1 Innovation Blvd EMERSON . Shakopee, MN 55379 1'1111" M.111 1111*111<*111 Calibration Data Sheet Conaiatont with ISO 10474 3.1 or EN 10204 3.1 Customer Information Manufacturer Information Name: WISCONSIN UNIVE RSITY OF Sales Order: 4748656 PO: CC.Andorson-09*Nov-16 Line: 1 Device Information Calibration Information Oovlco Typo: P1essure Tran~mlner Tag No: Factory: SHAKOPE ' MN, USA Station Name : S HA~CP LR_CALIBRATION_03 Serial No: 08873e' Operator ID: 45369 Model No : 3051S I CD4A2E1 2A 1AM50* Calibration Date: 11121/2016 8:22:* 4AM Modulo Serial No: 14409685 Output: Linear Internal Rel # 2004 111 3 1111111 UI I 1111 1111 II llJlll DOlll Equipment Used Calibration Data Range: 0.000 TO 300.000 PSI

%ot R1nge Applied Pre11 ure Rtaut 1t d Appt-.d Prt 11ure An*lov Output l""'l  % Spon E.nor P11.1Jf'1 ll 100 000 300.000 PSI 300.0000 PS I 20.000 10 0 00063 PASS 80.000 240.000 PSI 240.0000 PS I 18.80058 0 .00350 PASS 80.000 180.000 PSI 180.0000 PSI 13 !!0072 0.00450 PASS 40 000 120.000 PSI 120.0000 PSI 10.40092 0.00575 P>\SS 20.000 80.000 PSI 80,0000 PSI 7 .191132 -0 00* 25 PASS 0.000 0 000 PSI 0.0000 PS I 4.000!>2 0 00325 PASS This is to certify that the listed product meets the applicable Rosemount Specifications .

Measuring and test equipment used in the manufacture and inspection of the listed product are traceable to the National Institute of Standards and Technology. The calibration system was designed to meet the intent of ANSI 2540-1-1994 .

Kelly Klein Vice President of Global Quality, Approvals & EHS Page 1of1 JPEOB87364_Q4 -PRESSURE_RSK_1 65

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Reference Multimeter:

ICERTIFICATE OF CALIBRATION I P"g 1 01 Of 01 PRE ISION METROLOGY 7350 North Toutonla Avenue Milwaukee, WI 53209 (414) 351-7420

• FAX : (414) 351-74.29 11001960527 1 Cert! fi

• t Jon Nunll>Gr Gege ID HY41026086 .Manufacturer AGILENT Type NULTIHl!TBR AGILENT Jtt01A Model Number 3U01A Serial Number MY'1026086 comi>any UNIVERSITY Of WI

• MADISON/PHYSICS Size N/A Department N/A eel Date 0 1 /21/2017 Ca l ibrated By 1 MJQ Q&g* Calibrated a t Prec ioion H trolog y Next Cel Duo 01/20 18 Temp 73. 0 ' 1' Numidlty 29.0\RH Standard Uaed BD14H proc :MSP.0075 4(P)

This is to certify that the above instrument was ca librnted by Precision Metro logy u ing tandar*d lmccable IO the a tionnl Institute o f Sta ndards & Technology (N IST). The = ults indi tcd on this ccniticate relate only lo the item(s) c111ib111t d. Pn:ci ion Mclrology i accred ited to ISO/lEC 17025:2005 which sa t l~iici all req uirements of ISO 900 1:2008 & AN ' I/NC L Z.540-1:1994 . Un les

• otherwise shrted, ull o f the purnmetor.; cttlibrntcd on thi s cenifiCJ1te are within Precision Mctmlo&y's scope ofaccred itntion. The expa11ded me<isun:mcnt uncertainty i8 reported at km2, 95% confidence leve l. T his ccrtiticnte and auachmelll may not be reproduced, except in full , without the wrillcn approval of Precision Mctrology.

'ALlBRATlON STD(s) Ul!:SCRlll'IO N Cal Due Date Test Report#

ED034. 4 CALIBRATOR FLUKE 5520A WITH 600NH Z OPT 01/31/2017 1001 7 8 7551 TOLERANCE P8K MJ\N UP/\C't'UR~R ' S SPIJ Cl l' IC/\1'IONS SEE AT'l'ACHED SPREADSKBB1' F'OR RF.1\D I NGS CO l>ITlO RECEI VED WI 'TH I N MANUFACTURER'S SPBCfFICAT lONS RETURNED WITHIN MANUFACTURER ' S SPECI FI CAT I ONS Unless olhcrwl!ic stH1cd, '11(..il.!i:U rcn~n l:. h1 Yc bca1 compared to the umnod ifi cd loh.TMtK'-1.'ti. l\lld dimens iona l va l\1et m-e kfert>nct'd 10 68°P.

l'recis/011 Mc1ro/of!J"* ,...spo11sll>i/11y .1/toll /11 110 <'*'1!111. 11orfur n11y """*'" ll'ltni10t!1V!J' eraed 1/1e pm host price of1/Jis cerlificalio" um l'ng 1mi ss :r1ared

• • • • • • • * *********** ** ********--- *-----Last Page********* ****--**-*--**** -**- * **** **------ - -* **

CUa t no UNI:32D Control I 1001960527 Iuued1 01/2 4 /2017 1 3 119 134 Ce rt ed By i KJP 66

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Reference Handheld Thermocouple Reader:

lolliega.comI

~ .('EDMEGA"~

CERTI FICATE OF CALIBRATION Model: __H_H_S_OS_A_ _ Serial Number: __1_' _0 0_ 0_5 _66_

Omega Engineering. Inc .. certifies th at the above listod Instrument has been calibrated using standa rds whose accuracy Is traceable to the U.S National lnsbtute of standards and Technology, and meets or exceeds its pubhhed specifocabons. Calibration traceability of the above listed instrument is in full compliance with ANSVZ540-1-1994 standards and requirements ii' 20 m DATE L . Ii I. I.,. **c ng TESTED }

• I . ) i I ' ~

AUTHORIZED SIGNATURE 67

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Corio lis Flow Meter:

Foxboro by Schnelder Elecirlc I/A S*1riea Maaa l"lciwmeter CUSTOMER NAME ... . ... . UNIVERSITY OF WISCONSIN CUSTOMER DATA . . .. .. . . 03 - FE - 2002A.

FoxboroSAP, Number . . . 60166749/10 MODEL CODE . ...... ... . CFS10 - 08SCFNN-F Style . .. .... . .... . ... B Serial Number . ... . .. . 01063106 Calibration transmitter: CFTlO - .... s/n 6360040 .

Actual Flowrate Ind . Flowrate Error (lb/min) (lb/min) 193 . 5712 - . 046 193 . 6595 193.1751 193 . 1162 101.4576

-. 030 \

. 027 101.43 01 51 . 5955 51 . 5869 -. 017

20 . 1881 .066 20.1748 DENSITY and PLOW CONSTANTS Density Coefficient (DCll - 4 . 299400E+Ol Density Coefficient (DC2) +8.962600E+04 Density Coefficient (DC3) +l . 215900E - Ol Density Coefficient (DC4) - 2.555900E+Ol Flow Coeftici nt (PCl) ..... ... - 2.842200E - 04 Flow Coefficient (FC2) ... ..... +6.721100E - Ol Flow Coefticient (FC3) ... .. .. . - 6.9597006 - 07 Flow Coefficient (FC4) ........ +6.721100E - Ol Nominal Cap city .............. l. Sl AU. MSASUlllM&llT STA>IDAADS AJtll CALlllllATRD AT SCH I DUUD l llTlllVALS BY Tiii HATI OllA.I. lM.sTl'!Vn or STAMOIJU)S NII> TIOOIOLOOV INl ST) . ~ AQAfllS'I' ClltTIPllD STNll>AA.DS WHICH Alli TRAC'ICAllLll TO Tiii NATIOllA.I. JllSTJ1V1'1 or ST~S MID T'IOOIOt.OOY , l'OltHllLY HATiotlAL - u or ST.\llDIJUlS ( NU) .

Test Date ... .. . . 7/ll/2016 Calibrated by . . . LVN Approved by . . . .. . 7 /11 I

/1.6

~t FWd 0.vlc:ft, 38 lleporlMI A....

FOlllOIO. Ml 02035 USA T +I 11M17404Mn

"'""" r,. t *'

• r 68

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Appendix 5: Void Generation Sample Calculation 69

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A

1. Measure 0.25" lnconel Rod, set scale t o (6.35 mm)

2. Chop off (1.590 mm) from ea ch side of 0.25 11 rod~ leavi ng center region (w = 3.17 mm)

3. Looking at the cross section, shaded area is bubble measurement was taken. "y" cha nged slightly for each picture so splicing bubbles could be avoided - would be close to 3.5 mm.

y R, =H eater Rod = 3.175 mm Ro = Gius Rod (Inner diameter) = 8.017 mm A= Jll. i/% J Ri - x2 - J R; - xZ d

- Rd U9 A=

J - t .59 J 69.41 - xz - ho.OB - x2 dx A = 16.6745 mm*

Volume(totol) = A* y = 16.6745 mm 2 * ( 3.5) 58.4 mm 3 0.25 .

70

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Appendix 6: Rod Surface Roughness 71

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA A Zygo New View 6K White Light Interferometer (Figure 32: Zygo New View 6K White Light Interferometer was used to measure the surface roughness of the rods. The Zygo functions by directing white light at a surface and measuring the resulting interference caused by the reflected light to create a scan of the surface .

Figure 32: Zygo New View 6K White Light Interferometer Most rods were scanned in three places before and after testing to determine surface roughness .

These scans were done on the heated surface of the rod, namely the 0.25" diameter X 0.02"wall lnconel 625 tube . The first scan was near the bottom of the rod. The second was in the middle of the rod. The final scan was 1-2cm from the point of fa ilure. The software generates an image of the surface (Figure 33: Typical zygo scan of a rod surface) and calculates a root mean square (RMS) and roughness average (RA) which can be used to compare the rod before and after the test (Table 2 and Figure 34). The software is able to correct for the cylindrical shape of the rod so no extra calculations need to be done to the values.

72

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 /A Figure 33: Typ ical zygo scan of a rad surface Table 2: Surface Roughness Measurements RMS Before RA Before RMS After RA After

(µm) (µm) (µm) (µm)

Rod 1 (bottom) 0.726 0.575 Rod 1 (middle) 0.487 0.35 Rod 1 (top) 0.528 0.384 Rod 2 (bottom) 0.947 0.765 Rod 2 (middle) 0.461 0.331 Rod 2 (top) 0.583 0.437 Rod 3 (bottom) 0.287 0.234 0.527 0.416 Rod 3 (middle) 0.441 0.355 0.452 0.348 Rod 3 (top) 0.499 0.371 0.427 0.32 Rod 4 (bottom) 0.574 0.445 0.308 0.233 Rod 4 (middle) 0.373 0.274 0.314 0.245 Rod 4 (top) 0.458 0.37 0.318 0.24 Rod 5 (bottom) 0.357 0.279 0.442 0.343 Rod 5 (middle) 0.349 0.279 0.387 0.29 Rod 5 (top) 0.39 0.279 0.629 0.489 Rod 6 (bottom) 0.345 0.272 Rod 6 (middle) 0.284 0.224 Rod 6 (top) 0.303 0.225 73 I

J

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA RMS Change 0.3 0.2 0.1

• Bottom 0

• M iddle Rod 6

• Top

-0.l

-0.2

-0.3 Figure 34: RMS Change of Rods 3 -6 The change at the top of the rod is of particular interest because this is where the CHF occurs. It can be seen that the surface roughness typically decreases near the area where the CHF occurs, with rod 5 being an exception where the surface roughness appears to have increased . The middle of the rod is largely unchanged due to testing. The bottom of the rods indicate large variances.

74

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Appendix 7: List of Experimental Runs 75

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A CHF Run Conditions Index By date

• 01.05 .2017 o Conditions:

• Flow:-

• T;n(fixed): -

• Pressure: - i n l e t

• Notes on test results

• 01.10.2017 o Conditions:

• Flow: -

• T;n(fixed): -

• Pressure:--inlet

• 01.11 .2017 o Conditions:

• Flow:-

• T;n(fixed):- -

• Pressure:--inlet

• 01.26.2017 o Conditions:

• Flow: .

• Tout(fixed): -

• Pressure: - - outlet

• 01.27.2017 o Conditions: Data was not writing from NI (i.e. no NI data)

• Flow: -

• Tout(fixed): -

• Pressure : - - outlet

• 01.28.2017 o Conditions:

• Flow: .

• Tout(fixed): -

• Pressure: - - outlet

• 01.30.2017 o Conditions:

76

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA

• Flow:-

• Tou1{fixed): -

• Pressure: - outlet

• 02.09.2017 o Conditions:

• Flow:

• T0 u1{fixed): -

• Pressure: - outlet

• CHF at - failed rod #3

• High speed videos at

• 02.21.2017 o Conditions

• Flow:

• T;n{fixed) : -

• Pressure: - {actual pressure - due to neglected head pressure)

• Heat Flux:

• High speed videos at 3 locations; top, middle, and bottom of heater rod

• 02.21.2017 o Conditions

• Flow:

• T;n{fixed) : -

• Pressure: - inlet {actual pressure - due to neglected head pressure)

• Heat Flux:

• High speed videos at 3 locations; top, middle, and bottom of heater rod

• 02.21.2017 o Conditions

• Flow:

• T0 u1{fixed): -

• Pressure: - outlet

• CHF at - failed rod #4

• High speed videos at

• 02/23/2017 - Run 1 o Conditions :

• Flow:

• Tout{fixed) : -

• Pressure: - outlet

• CHF at 77

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA

• 02/23/2017 - Run 2 o Conditions :

• Flow:

• T0 u1(fixed): -

• Pressure: - outlet

• CHF at failed rod #5

• High speed videos at

• 02/24/2017 - 02/27 /2017 o Conditions:

• Flow:

• Tout(fixed) : -

• Pressure: - outlet

• CHF at 78

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Appendix 8: Mechanical Drawings (All Dimensions in Inches) 79

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Heater Rod Assembly: inches Lower Copper Fitting Lower Copper Lead Lower Voltage Sense Wire lnconel 625 Heater Element Internal Thermocouples (2)

Upper Copper Lead rr Upper Voltage Sense Wire Upper Copper Transition

( ; Upper Copper Tube

• 5.1450 17.97 2.2796 0.6000 Heater Rod Components, inches Lower Copper Fitting Lower Copper Lead r002soo

--00.1600 00.0938 lnconel 625 Heater Element 80

Attachment 1 O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Heater Rod Components, inches Upper Copper Lead 0 ~g 1~~0~ Z1 r o.1250 00.1700 ~I: 34° t).r-:-: =-== =~

- =-==-==-=-==-==-=-==-==-=-==-==-=--.

1210.0938 \ L 2.7546 .I Upper Copper Transition 00.6250 Upper Copper Tube

- - - - - - 1 9.0 0 - - - - - - -

.-------'/ - - - - - - - .

-- -.- -- --- -- -- -- - -- J

/

L ___ -- -- -- --- -- -- -- -

__ J______________ l,L_____________________ _

--1 00.3830 1

--' o .3000 7I ~Stamp this end 81

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Test Section Components: inches 1/16" Diameter Nea- Rod Top Thermoco~l e I ~WS, 150# 316SS Custom Blind Flang e

-1 "NPS Cone. Redocer 316SS Custom Blind Flange:

2"NPS,150lb, Blind Flange, 1 Required O-rin9 G move

1. 14 9 ring

~=--<-- 0. 1 250 Central Hole Orill 29164 Thru Tap 1/2-13 thru 0 .649 5 Smooth Finish\

This Surface I! ! i 82

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Test Section Components: inches 31688 Flange Beneath Test Section:

2"NPS ,150lb, Sch40 bore, Weld Neck Flange, 1 Required 1.5000 iI ,

i iI 0-ring Finish This Surface 00 .7500 4 Existing Holes Leave as Suppl iad Lower Transition 1 Req'd, 316 SS 1-11000 01112 H>**

t .S-0 Tlllll O*ll 4 llolHf:U Thru Tlp&-32 Thru Spo l ~ico41polli, .!0)(0.40p 83

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Test Section Components: inches Upper Test Section 1" Ultra Torr Fitting Mach ine Length to Dim(0.31 cril} Upper 1" Ultra torr spacer Tack in Spacer 316SS, Machine 0.875 to fit I 1 03100 0.9~

L~~00 00.8750 ((+)) ---

006- y Lower 1" Ultra Torr Fitting Leave at original Length Tack in Spacer Lower 1" Ultra torr spacer l~ I . ~I 316SS , Machine 0.875 to fit I 0.8100 I 1.8500 ---- ____ ;

((+)) a- ~----:-

Ll µ j

. : _J l

ostoo l..J.

o.stoo 00.8750 - : : : r 00.6560 L 1'"°"_J

• Upper Transition 1 Req'd, 316 SS

.9000 t

.3000 4Holff Odil TllnJ 1!32 Tapt111116-3.2 Spct Face 0.5"0, 0.037S"llp 84

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Test Section Components: inches Flange /lbove Test Section , 316SS:

2"NPS,1501b, Sch40 bore, Weld Neck Flange, 1 Required 45.00' 0 0.7500 4 Existing Holes Leave as Supplied 1.6794 Smooth Finish This Surface

\

i i i 0.1250 0.4076 Top Flange 316SS:

2NPS,150lb, Sch40 bore, Weld Neck Flange, 1 Required 00 .7500 4 Existing Holes Leave as Supplie d 85

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Test Section Components: inches Hex Spacers 4 Req'd , 6061AI Dril 5/16 Tap 316-16 1.2500 Borosmcate Glass Tube, 6 Req'd t ~ ~

1.5000  ; i

~

~--+---.-.

1~

• -~

Dril 17132 00 . 9850 ~

Tap 518 @

00.6560 ~

Upper Electrical Connector Blocks, Copper 2 matched pairs required "o.e25o

' I'

' I '

' !i!-0 :i:

' I

' I

' ' ' +

' I '

'I'

. ~ ! ' I

' I

002660

. . . . . . _ - - - - - - e.!iOoo------____..

86

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 /A Exit Plenum v'""..-.,&+----+n~--- 0. 383 0

~--1..-;---+fi'-*""---0_6 250

"--2"NPS, 15<J b, Sch40, 316SS 1116" o_Thermoco'-"le Weld Neck Fla-iges

, w r Pressure Tap~

0.2248 1_901 2 2.0262 Ulra Torr H l i n g - - -1 Glass Tu be -

87

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Entrance Plenum Tra.n Etbn 1D Hl!ilt!ll Rlld

~ D. s.aHd CDpper Round 2..22:9'"! 2.. D4 2 The-rm COOpll!' P rt'\.

.225 2 r2"11PS, SCf', SCll40, 3 6SS

I Cu&ta Weld Nect Flangl!'

.7500 ~~...,..,.....,.....--'17""":1

3. gs~

---2 -., .,\._:t"NPS, '° *ss R!'dU cer Cu EID Blind Fitngl!'

88

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A Appendix 9: Computer Platform and Software 89

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 IA Program Name Labview 2013 Version 13.0f2 (32-bit)

Developer National Instruments Special Cond it ion s None Type PC Ma nura cturer Dell Model Optiplex 780 Processor lntel 8 Core"'2 Duo CPU E8400 @3.00Ghz 3.00Ghz Installed Memory (RAM) 4.00 GB (3.87 GB usable), DDR3 1066Mhz/1333Mhz Memory Video Card ATI Radeon HD3450 CD/DVD drive HL-DT-ST DVD+ -RW GH50N Monitors (2) Dell ASUS VH222 VerH-P, DELL 1704FPZT 90

Attachment 10 Critical Heat Flux Testing at the University of Wisconsin Final Report 30441 R00041 I A

=Iii Wndowsedition Wn>>M17Pn:if~

Copyright Cl 20'5 Micrmoft COfP0'.6on. Al rights ttttr"M:d.

°"'

°""""'""

• I Windows &perimce Sncks lntet(R) COtt(TM)l Duo CPU EMOO 0 J.DOGHz J.00 GHz

........ .......,.~ 4.00G8 (3.17G8""'"<J ATAChtnndl ........ type ..... """"""* Sy<t....

Stan~rd Ou.. Ch.nnd PCI IOE Controller Pen Md Touch: No Pen or Touch Input is w1bblt: fortt"50dp&ly HO._.,.o..K.

• 0 Mice and other pointing dMcn

- 0 t<<>-compiant mouse Monitors Generic PnP Monitor CMn<<ic: PnP Monitor

~ c~ name ThermalHydnuli

• 'I -

r-<*

C11eo Any(.onnect Sewn: Mobiity Ch:nt Virtu.1 Minipoft Ad..pter for Www:toM i64

,.......... ~

__. lntd(RJ 12567l.M*J Gi~bit Ndwort Connection Wotkgroup: WOf!KGROUP

• 'f Ports (COMl!llPT)

Communications Port (COMl) w.ndows Kb.ration

- ECP Printer Port (l.PTI) ......,I>. ______

wr.dows is adW-.trd

- lnt<IOQ ..... "'"'9...,...T<<hnology-!Ol (COMJ)

• C Processors r-0 lntd(R) COfe(TM)l Duo CPU EMOO JJX>GH:o I. Q lntol(!Q C..e(TM)Z Duo CPU <MOO 0 J.llOGtU Sound, video Mld 9lf'l"lf: contrcnen SoundMAX r....-md o;,;t.i fi9" Star* controffet

°""'"""' .....

()- lnt<IOO ICHIR/IC~OIVOOIS s.riHIJ<<IO s.rin SATA RAID C -

V~ C~

Systtm~n ACPI f'oied k.turT Bufton ACPt Pf!Nttl Button Composite Bus Enurna'.tor

,. Dftd memotY teem cOfltrohr 91

Attachment 1O Critical Heat Flux Testing at the University of Wisconsin Final Report 30441R00041 /A Device Manager = @]

File Action View Help Ports (COM & LPn

~ *C Processors I> ** Sound, video and game controllers 1> .* - Storage controllers System devices ACPJ FDced Featu re Button ACPI Power Button Composite Bus Enumerator Direct memory access controller High Definition Audio Controll er High precision event timer Intel(R) 4 Series Chipset PC! Express Root Port - 2Ul Intel(R) 4 Series Chipset Processor to VO Controller - 2E10 Intel(R) 82801 Pa Bridge - 244E Intel(R) ICl-llO Family Pa Express Root Port 1 - 3A70 lntel(R) ICHlO Family PO Express Root Port 2 - 3A72 Intel(R) ICHlO Family SMBus Controller - 3/Jl/J Intel(R) ICHlODO LPC Interface Controller - 3A14 Intel(R) Management Engine Interface Microsoft ACPJ-Compliant System Microsoft System Management BIOS Driver Microsoft Virtual Drive Enumerator Driver Microsoft Windows Management Interface for ACPJ Iii NI Ethernet Device Enumerator Numeric data processor PO bus Plug and Play Software Device Enumerator Programmable interrupt controller Remote Desktop Device Redirector Bus System CMOS/ real time clock System speaker System timer UMBus Enumerator UMBus Root Bus Enumerator

.. .. Universal Serial Bus controllers lj Intel(R) ICHlO Family USB Enhanced Host Controller - 3A6A lj Intel(R) ICHlO Family USB Enhanced Ho!il Controller - 3A6C lj Intel(R) ICHlO Family USB Universal Host Controller - 3A64 lj lntel(R) ICHlO Family USB Universal Host Controller - 3A65 lj Jntel(R) JCHlO Family USB Universal Host Controller - 3Ati6 lj lntel(R) JCHlO Family USB Universal Host Controller - 3A67 lj Jntel(R) ICHlO Family USB Universal Host Controller - 3A68 lj lntel(R) ICHlO Family USB Universal Host Controller - 3A69 lj USB Root Hub lj USB Root Hub lj USB Root Hub lj USB Root Hub lj USB Root Hub lj USB Root Hub lj USB Root Hub lj USB Root Hub 92 0

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