ML20071P610

Nonproprietary Verification of CP&L Ref BWR Thermal- Hydraulic Methods Using Fibwr Code

ML20071P610
Person / Time
Site:	Brunswick
Issue date:	05/18/1983
From:	Kunita R, Michael Pope CAROLINA POWER & LIGHT CO.
To:
Shared Package
ML19268B607	List: ML20071P605 ML20071P610
References
NF-1583.04-(NP), NF-83-139, NUDOCS 8306080083
Download: ML20071P610 (41)

Text

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NF-1583.04 NONPROPRIETARY VERSION VERIFICATION OF CP8L REFERENCE ,

BWR THERMAL-HYDRAULIC flETHODS IISIflG THE FIBWR CODE TOPICAL REPORT MAY 1983 I

Cp&L Carolina Power & Light Company hh6080003830531 p ADOCK 03000324 PDR

NF-1583.04 SERIAL: NF-83-139 Verification of CP&L Reference BWR Thermal-Hydraulic Methods Using the FIBLTR Code M. A. Pope May 1983 Approved By 8, [, U R. K. Kunita f /7/G (Date)

Principal Engineer - Surveillance & Accountability Carolina Power & Light Company 411 Fayetteville Street Raleigh, North Carolina 27602

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DISCLAIMER OF RESPONSIBILITY This document was prepared by Carolina Power & Light Company and is b211rtved to be completely true and accurate to the best of our knowledge and information. It is authorized for use specifically by Carolina Power & Light Company Ior the appropriate subdivisions within the U.S. Nuclear Regulatory Covcission only.

With regard to any unauthorized use whatsoever, Carolina Power & Light Company and their officers, directors, agents, and employees assume no liability nor make any warranty or representation with regard to the contents of this document or its accuracy or completeness.

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ACKNOWLEDGEMENTS The author wishes to acknowledge the code development and qualification w:rk performed by Yankee Atomic Electric Company.

Special appreciation is extended to K. E. Karcher and B. J. Gitnick for the many valuable comments and suggestions on the use and understanding of the code.

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ABSTRACT The verification of a steady-state core flow distribution code (FIBWR) is described for applications specific to Carolina Power & Light Company's Brunswick nuclear station. The ability to predict core pressure drop, bypass flow, and inter-assembly flow distribution is demonstrated by comparisons to

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plant measured data and process computer calculations. The ability to GItablish critical power ratios (CPR) as a function of fuel assembly power is clso demonstrated by comparisons to vendor data.

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TABLE OF CONTENTS Page 1.0 Introduction . . . . . . . . . . . . . . . . . . . . . . . I 1.1 Description of FIBWR . . . . . . . . . . . . . . . . I 1.2 FIBWR Applications . . . . . . . . . . . . . . . . . 2 2.0 CP&L FIBWR !!ethods . . . . . . . . . . . . . . . . . . . . 4 2.1 Geometric Models . . . . . . . . . . . . . . .. . . 4 2.2 Determination of Form-Loss Coefficients . . . . . . . 5 2.3 Determination of Bypass Flow Coefficients . . . . . . 5 2.4 Hydraulic Models . . . . . . . . . . . . . . . . . . 7 3.0 CP&L FIBWR Benchmarking . . . . . . . . . . . . . . . . . . 14 i

3.1 Verification of FIBWR Pressure Drop Predictions . . . 14 l 3.2 Verification of FIBWR Leakage Flows . . . . . . . . . 15 l

! 3.3 Verification of FIBWR Flow Distribution . . . . . . . 17 l

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3.4 Verification of FIBWR CPR Methods . . . . . . . . . . 17 1

4.0 Summary and Conclusions . . . . . . . . . . . . . . . . . 31 l  !

i 5.0 References . . . . . . . . . . . . . . . . . . . . . . . . 33 l l

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LIST OF TABLES Trble Number Description Page 1 Brunswick Plant Specific Data and Rated Conditions . . . . 9 2 Form-Loss Coefficients Used in FIBWR . . . . . . . . . . . 10 3 Summary of Flow Fraction Through Bypass Flow Paths . . . . 12 4 Summary of Leakage Coefficients for Bypass Flow Paths. . . 13 5 FIBWR Comparison to Process Computer Core AP , . . . . . 19 6 FIEWR Comparison to Measured AP . . . . . . . . . . . . . 21 7 FIBWR Comparison to Process Computer Bypass Flow . . . . . 23 l

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LIST OF FIGURES l

Figure Number Description Page 1 BWR Bypass Flow Paths . . . . .. . . . . . . . . . 11 2 FIBWR Comparison to Process Computer Core 21P . . . 20 3 FIBWR Comparison to Measured zip . . . . . . . . . 22 L

4 FIBWR Comparison to Process Computer Bypass Flow. . 24 5 FIBWR Comparison to Process Computer Flow . . . . . 25 Distribution 6 Critical Power Ratio vs. Bundle Power . . . . . . . 29 7 FIBWR Comparison to Vendor Critical Power Ratio . . 30 i

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1.0 Introduction .

The purpose of this report is to demonstrate the capability of Carolina Power & Light (CP&L) to perform independent, steady-state BWR analysis, using the FIBUR code. The qualification and verification report (Refer-ence 1) on FIBWR was submitted in December of 1980, by Vermonc Yankee Nuclear ?ower Corporation, and subsequently reviewed by the NRC Core Performance Branch (Reference 2). The Yankee submittal which contains the qualification of the hydraulic models in FIBWR, as well as a compari-son to a fully verified thermal hydraulics code, has been published as an EPRI report (NP-1923, Reference 3). For this reason, this topical report will not repeat the FIBWR qualification, but will concentrate on the use of FIBWR.by CP&L and its application to our Brunswick nuclear plant.

1.1 Description of FIBWR FIBWR (Flow In Boiling Water Reactors) is a steady-state thermal-hydraulic computer code developec to model the pressure drop, enthalpy rise, void fraction, critical power ratio (CPR), and flow distribution in a BWR. The code solves the equations of mass,

! momentum, and energy while iterating between core pressure drop and required core flow, calculating variations in leakage and water-tube

! flow during each iteration. FIBWR was written by Vermont Yankee and j made available to CP&L through the Electric Power Research Institute. l I

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1.2 FIBWR Applications CP&L intends to use FIBWR in the following applications to the Brunswick Plant:

Calculation of the bypass flow splits for the system transient analysis code (RETRAN)

Hot bundle analysis of slow transients Hot bundle initial conditions for systen transient evaluations Calculation of steady-state thermal-hydraulic core conditions for use in the nodal simulator (PRESTO-B), training simulator, and plant process computer Investigation of core anomalies (e.g., local power peaks, flow maldistribution)

Calculation of pressure drops across internal components, such as channel walls, core support plate, and core shroud l

i Bypass boiling analysis

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Evaluation of CPR-power relationships l

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This topical will demonstrate the ability of the CP&L FIBUR model to accurately perform calculations required by the above applications.

Section 2.0 is an overview of the methods used for steady-state hydraulic simulations and a discussion of FIBWR input. Section 3.0 provides a verification of the FIBWR capability to match vendor-calculated and plant-measured pressure drops, flow rates, and critical power ratios.

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l 2.0. CP&L FIBWR Method l

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FIBWR has great flexibility in the way it can model vertical parallel channels, allowing for an accurate representation of unique flow condi-tions. The BWR core can be divided into as many as 100 channel types, with a common bypass region. Single channels can be defined as a sepa-rate region for specific study, or can be analyzed individually with controls on the leakage flow to depict active bundle power and flow.

Additional flexibility enables the user to either specify total core flow and havo FIBWR solve for the pressure drop, or specify pressure drop and allow the code to solve for core flow.

2.1 Geometric Models Geometric modeling of each fuel assembly is quite detailed, includ-ing inlet orifice, fuel support piece, lower tie plate, heated and unheated rodded regione, spacers, water tubes, upper tie plate, and ,

exit region. The CP&L FIBWR model includes the actual physical dimensions of the fuel and core compenents at the Brunswick Plant.

l Much of this data was taken from fuel outline drawings, while the l

lower internals and core design data were obtained primarily from Brunswick specific documents and published General Electric reports.

A summary of Brunswick Plant data and rated conditions is given on Table 1.

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2.2 Determination of Form-Loss Coefficients Single-phase form-loss coefficients are required as input for all locations along the vertical channel where there are changes in the channel cross-sectional area. All loss coefficients are referenced to the flow area of the fuel assembly. The Brunswick form-loss coefficients for both the interior and peripheral orifice zones,

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along with their respective flow areas, were provided by General Electric. in Reference 4.

The form-loss coefficients for the lower tic plate, spacer grids, and upper tie plate are those provided in Table 5-1 of the FIBWR Oualification Report (EPRI-NP-1923). These values are fuel-specific, and were developed for application in the FIBWR code. The entrance loss coefficients for the water tubes were determined by running FIBWR to match the water tube flow to that stated by GE (Reference 5) for given bundle power and conditions. -Table 2 is a list of form-loss coefficients used in the CP&L FIBWR model.

2.3 Determination of Bypass Flow Coefficients The complex system of BWR leakage flow paths is illustrated in Figure 1. The leakage flow in each path is represented in FIBWR

, by the equation:

W = C1 ? P + C2 - AP + C3 AP , Eq. I where

W = flow through the leakage path (Ibm /hr) F w

AP = driving pressure differential for the W

w leakage path (psi) --

C1,C2,C3,C4 = analytically or empirically determined -

leakage coefficients F_

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The method described in Section 5.1.4 of EPRI-NP-1923 was used to calculate leakage coefficients for the CP&L FIEk'R model. However, N

-=^

the flow through each leakage path was expressed in terms of the _-

e flow through the lower tie plate holes (path 9) rather than flew P

r g

through the finger springs (path 8; see Figure 1). A form of

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Equation 1 for the flow through path 9 is given in Reference 6. -

From this equation, the leakage coefficient, C1, for path'9 was E defined, and leakage coefficients for each of the other paths were i*

then determined by the ratio of their respective bypass fractions.

Table 3 shows how the flow fractions generated from a FIBb'R run A compare favorably with the intended CE values (Reference 5). [

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.w Leakage flow through the finger spring path is known to increase as N w_

a function of exposure due to fuel channel deflection. An effort

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was made to represent this effect in the CP&L FIBWR model by estab-lishing separate path 8 leakage coef ficients fc.r new and used fuel. E m

The flow fraction for the finger spring path provided by GE for >

F Brunswick 2, Cycle 5, as well as the coefficient C1 calculated for L

this path, represents a mixed core of new and used fuel; whereas, the coefficients defined in EPRI-NP-1923, Section 5.1.4.1, for path [

8 were developed from a flow test involving clean fuel.

By weighting _y_

M N "

m

w .?

. <.y , v. m - ..s ,...,.v:. m- .n.

.< -,u > . . r .- .: ~ ~ . r . - - - .o- r  :. ..,

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e, the flow through the finger spring path by the number of new and ?i[ '

fr . .

used fuel assemblies in-core during Cycle 5, a leakage coefficient . ./c, ~

y

f."el. .

representative of used fuel was determined as shown:  : j.- -

c i.M. j

, ,. ' :1 (A) Wmixed - (B) Wnew = (A-B) Wused Eq. 2

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(A) Cl mixed AP - (B) 702 AP* = (A-B) Cl used AP Eq. 3 s .,

q_.,...

Solve for C1 i '+ '~ n 7 used a.

where A = total number of assemblies . f.# $

s _ ... . ,

B = number of new assemblies "if <C,{.

p.,, . . ., <

AP= differential pressure across channel wall " 4. : '

? , R; ,

,., :Q' ..

q .jQF '

9 A summary of leakage coefficients used in FIBUR is shown in Table 4. 1:h f' . .;..

$$'?W l  ?, ,;m.Q

.. . s e 2.4 Hydraulic Models 1.'.,;Wl q% .; ,

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. ,v  :}. ,'7. -

A,'

3.~$'s .[

l FIBWR includes a selection of friction multipliers and quality f' \ ' -

, s

'? x :: .

.I relationships available as input options. The following models i': 'n.,- -

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were selected for use in CP&L's steady-state methods: . . , .

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E ., : '. * .: . .

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a. Blausius single-phase friction factor expressed in the Hr.d' - -

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.9 e .s =3.

t- t$;_- ,.', q. q ,.

y". % . 2, : .

,;3jy'.-

f = AR, B Eq. 4

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81

- r rx  %, , ;.w '

where R e = single-phase Reynolds number -t . " -

x _ : . ., ;,

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1 A,B = input coefficients provided in Reference 7  !.t

,e.y e .,

+; .

9;='  ; .. ? ' ,-

g; . .-

'*' ~

9 - ';;.

'6.,,

.'*r_

f

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W.

. .'[ E . t'

. . , .  ?. Y*

? ' . ', y*Nh . .

' { ,.,. '?.'Y '

^N_

.. ~ hy'*3 W-'~I,')..',*'-.K

, . . ~ '.. ., - '

• .,,-4 *'

,' l. 'a :5 .

. W . . . . .*?

, '.) '*

.-c_;,r,-sn, .

.,.,.e.  :.- -

8.. .~........ .o. .,-.,.,w. -. s. - . . _ .x <. . , . ,

.c . , ,

+ - - - - - - . ;_ , ,-

W. ~*a..

_g_ - %

m_

.3- .

4 .e . ,y; *'..

b. "* '

Homogenious two-phase, form-loss multiplier (Reference 8),

5.~__ c.,

given as (,,

r.-

.e , - wn O

2-phase local

= 1 + X ( #,/.

1. 8 -1) Eq. 5 4

. \ , .,. .

v f -

.. 4 i - 1 3 _ -. .

with x = flow quality ' ;; 2, .

< ^

> # ,# = saturation densities 1 8 -[ i * -.

- s ,

y .- .. ' - e 6; q ,, . i.

4 h'k ,l:

~{ c. Baroczy two-phase friction multiplier. FIBWR interpolates , K ' /* --

- .. ..e. -

i to a value of the friction multiplier, which is graphically f].b ,' : .c j.~ , -+ y..,:( e i

expressed in Figures 5-16 and 5-17 of Reference 8. $ ;. - , r' A -t (

[  ;;;;, . .

,- , . *g , ;-

-2

d. EPRI void model (Reference 9) for void quality and initia- w. 7 -.u . \.f.-- .

.-s '. " :7-

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tion of sub-cooled boiling. i?.

. , , - 3, I j.: .. t

s. ,

,r..

These hydraulic models are those recommended for use by the FIBWR .,

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Qualification Report and were included in the NRC review of the . u f , sg4. ,3;. ,

c Vermont Yankee submittal. V.

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pg a 1 ' ,  ;

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A5 , t b-n .. . g .

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-9 TABLE 1 BRUNSWICK PLANT SPECIFIC DATA AND RATED CONDITIONS Core Thermal Power 2436 MWe Core Flow 77 Mlb./hr.

Total Number of Assemblies 560 Number of Control Rods 137 Number of Incore Instruments 31 Number of Central Assemblies 484 Number of Peripheral Assemblies 76 Unit 1 Central Orifice Diameter

• Unit i Peripheral Orifice Diameter Unit 2 Central Orifice Diameter Unit 2 Peripheral Orifice Diameter '

Number of Spacers per Assembly 7

• Bracketed information is General Electric Company Proprietary.

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_c* _ _ _ _ _ _ _ . _ _ _ . - - - _ - - . _ . - - . - - - .

TABLE 2 FORM LOSS COEFFICIENTS USED IN FIBWR m

7x7 _

7x7 Orificed 8x8 8 x 8R -

Orifice, Unit 1 Central

• Orifice, Unit 1 Peripheral Orifice, Unit 2 Central [

Orifice, Unit 2 Peripheral j -

Lower Tie Plate 7.58 [ ] 7.56 7.86 ,

Spacers 1.21 1.21 1.38 1.24 Upper Tie Plate 1.35 1.35 1.41 1.46

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Water Rod Entrance ] i Note 1: K's for the orifice, lower tie plate, upper tie plate, and spacers are based upon the flow area of the fuel type they are listed under.

Note 2: K's for the entrance of the water rods are based upon the flow area of the water rod of the fuel type they are listed under. 3 Note 3: 120 initial core assemblies contained a 1.3-inch diameter orifice in -

the lower tie plate.

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• Bracketed information is General Electric Company Proprietary.

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FIGURE 1 BWR BYPASS FLOW PATHS Top of Core h

j ZCH1 e

ZUHA a o -

h ZHET l l supports are welded into the core support plate. For these

- bundles, path numbers 1, 2, Channel 5 and 7 do not exist.

V Spring Plug ZUHB

_ ore Support J 8 a

Lower H Tie 9 ZGEO Plate f 6.

'h v

- "U ,3 t Bottom Id of core ZSTU

- -N A"?- ,,

Fuel Support Control - Shroud lb Rod Guide Core Length = ZCHI + 6 Tube Fuel Length + ZGEO

1. Control Rod Guide Tube - Fuel Support Fuel Length = ZUHA + 2. Control Rod Guide Tube - Core Support ZHET + ZUHB o 5 P

Plate 7 3. Core Support Plate - Incore Guide Control Rod Tube Drive Housing 4. Core Su'pport Plate - Shroud

5. Control Rod Guide Tube - Drive Housing

6. Fuel Support - Lower Tie Plate

7. Control Rod Drive Cooling k'acer

8. Channel - Lower Tie Place

9. Lower Tie Plate Holes

10. Spring Plug - Core Support

' Figure 1-2. Fuel Bundle Geometry and Various Leakage Flow Paths (Front Reference 3)

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TABLE 3

SUMMARY

OF FLOW FRACTION THROUGH BYPASS FLOW PATHS Fraction of Fraction of Bypass Flow Bypass Flow ath Number Path Description (FIBWR) (CE, B2CS)

A 1 Fuel Support Casting / Control Rod Guide Tube '

3 2 Core Support Plate / Control Rod Guide Tube .

0.350 5 Control Rod Guide Tube / Control Rod Drive Housing , _

3 Core Support Plate / Instrument Guide Tube 0.002 's 4 Core Support Plate / Core Shroud 0.001 -

6 Fuel Support Casting / Lower Tie Plate 0.015

}

7 Control Rod Drive Cooling Flow 0.004 j 8 Channel / Lower Tie Plate 0.278 9 Lower Tie Plate Holes 0.345 10 Plugged Holes in Core. Support Plate 0.005 T

racketed information is General Electric Company Proprietary. -

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- A

1 -

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TABLE 4 5

SUMMARY

OF LEAKAGE COEFFICIENTS FOR 5 BYPASS FLOW PATHS

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Flow Path Description C1 C2 C3 C4 2 Channel - LTP (Path 8) New Feel 0.0 702.0 0 . 0' O.7106 Old Fuel 1624.2 0.0 0.0 0.0 2

LTP Holes (Path 9) 1782.0 0.0 0.0 0.0 -

Fuel Support - LTP (Path 6) 77.25 0.0 0.0 0.0 $

Control Rod Paths (1, 2, 5) 4380.0 0.0 0.0 0.0 Instrument Tube (Path 3) 120.1 0.0 0.0 0.0 Core Shroud (Path 4) 1861.7 0.0 0.0 0.0 -

Plugged Support Plate Holes (Path 10) 120.9 0.0 0.0 0.0 1

• The Coefficients C1, C2, C3, and C4 are constants in the equation: .

W = C1 AP + C2 AP + C3 AP j where W = Flow through the leakaga path (1bm/hr) 2 AP = Driving pressure differential for the leakage path (psi,

=

A

=

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3.0 CPOL FIBWP. Benchmark I

L Comparisons were made to vendor-calculated and plant-reaserts data in g order to verify the CP A FIBUR model. The Brunswick 'lant p ro c s.s s computer served as a source for plant operating conditions, such as power, flow, pressure, inlet sub-cooling, and potrir shapas; as well as benchmarking data in the form of pressure drope and bur /Le flow ra:es.

Vendor data was available in the form of process ccapoter input a n.:

supplemental reload licensing submittels for the Brurswick Plant.

3.1 Ve d fica t tor of StBRh F-essure Drop Predictions f IBM compat iscas were ma :e to the core pressure u op obtained from the >l edit of the plant process compt.?et. Bet 1 moc' e ls use an iterati"e ulculaticnal technique to determine cate p essure drop

.w d a s setub !.v flow rates. Unlike FlBWR, now.'ar, the process cotopu-ter model does not have a complete there11-hyornulii. representation of the core and fuel. The leakage flow, for example, is auutrically omitted; and the core pressure drop is corrected for this by cdjust-ments to the orifice loss coefficients. In addition. +he tso-phase friction model actaally utilized by the process computer is a curve fit to data points aased on a more detailed pressure drop model.

Table 5 shows the FIBWR-calculaced and process computer-calculated core pressrra drops at variou flow and power conditions for each cycle of Brunswick operatior. The average ratio of process computer to FISWR values is 0.99, with a at mdard deviation ci 0.05, illus-

=

mm.y y n. .m

4

-C

t. rated gt3phically in ?ig.re 2. The differenca between the two -

- mod >.11 for brunsaitk 2, Cycle 3, is due to the calculated coeffi- .

e cients for th:e hydrau'ic model utilized by the process couputer.

The process compocer da;abov: indicates that these coef fi:'s ts were - 4 h-g different For Cycle 3 than tho.:e ese) in previous cycles and tor tra _

a-g following cy le.

F S FIBWR alco calculares the p re s st. re drop across the core support _-

g plate. ~hia can be ccmpmred directly with plant-measured data.

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Several cases from 3 run swick 1, Cycle 3 (Table 's and Figure 3T, .-

g  :

y exemplify the difference between FIBWR-predicted and measured core K s- -

L -

{ support plate pressure drops. It can be seen from Figure 3 that if g- FIBWR shows better agreement with ceasured data at higher ficus rhan s lc -

E ar low-flow condi,tions. Jet-puttp flow measurecents at Peach Bottom E

(Reference 10) indicate that the process computer uses a jet-pump -.

{ flow calibration method that rccurately represents Flow at rated _

_ corditions, but conservatively underegrimates flow a .: lower flow E

rates, result ing fn FIBWR pressure drop predictions below the __

seasured values. The average c.easurc3-to-FIBWR tut 2cs for the data .

in Table 6 is 1.06, wf th a standard devit tion of 0.06.

=-

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3.2 verificad s o_f_JI_ BUR Ledage Fl.ows b

= -

{ An addit ionc i ^.cTparison was me.te tc den on stra te the ability of the JP&L FILWR u.edel t7 7.redict the : ore bypass flow. ine Brunswick a.: -

=

P!arir p ccess computer databnok pcovidas cycle-specific bypass : low

.h mi

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R:

1 as a function of total flow along the 100-percent rod line of -

the power flow map. From this data, bypass / total flow curves are j generated for each cycle. Although these curves can be used to -

estimate leakage flow from a given core flow, they do not correctly ,

model bypass flow away from the 100-percent rod line.

Bypass flow rates were calculated by FIBWR for various power and flow conditions for each of the Brunswick operating cycles. The }

total flow rate for each case was then used to estiente the bypass 1

flow from the bypass / total flow relationship. A comparison of the l l

two methods is shown on Table 7 and Figure 4. The distribution of  ;

i the data points produced an average ratio equal to 1.00; however, approximations by the bypass / total flow curves resluted in a stand-ard deviation of 11 percent.

i High-flow, low-power conditions have void fractions below those .

typically expected when operating along with 100-percent rod line.

A decrease in voids with a constant core pressure drop results in an increase in the active flow, and therefore reduces bypass flow. For those cases near the 100-percent power-flow line, FIBWR-calculated -

bypass flow rates are in agreement with bypass flow rates predicted from the process computer databook. As expected for those cases .

with power levels below the load line core power for a given flow, f bypass flow rates calculated by FIBWR are lower than if estimated i

from the bypass / total flow curves. Several such cases from Bruns- -

uick 1. Cycle 1, are clearly shown on Figure 4. i i

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=

1 m

--isumme --- - um=

d

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3.3 Verification of FIBWR Flow Distribution In a steady-state system of parallel vertical flow channels, the y pressure drop from inlet plenum to exit plenum is constant, regard-i-

less of the flow path. For this reason, in a BWR core with many m

channels of similar geometry, the flow distribution is a function of the density distribution and therefore ultimately dependent upon the power distribution.

The process coraputer provides cora-wide, bundle-specific rcdial it peaking factors and bundle flow races. Eighth-core synnetric,

}

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75-ch;nnel FIBWR modelc were established matching the core power

[ and flew conditions, and specifying the independent Sundle power factors from the process computer edits. Both high-flow and lor-flow cases were selected from each Brunswick Unit. Figures 5A

=

through SD compare the resulting channel flow rates to- the process T computer values. RMS differences between FIBWR and the process h computer flow distributions were calculated from the data on these figures. The largest RMS difference was found to be 1.58 K1b/hr,

[

which represents only about 1.3 percent of the channel flow rate.

3.4 Verification of FIBWR CPR Methods L

E The GEXL (Reference 11) critical power correlation has been included in FIBWR for use in CP&L's steady-state methods to calculate CPRs.

I A FIBWR model of Brunswick 2, Cycle 5, at rated conditions was

._ established with a single interior channel designated as a hot I

E

channel. By increasing the relative power of the hot channel, the bundle power /CPR relationship, shown in Figure 6, was developed. In this way, the FIBWR : ode can be used to establish limiting bundle conditions for a specific critical power ratio. Several data points from Brunswick 2, Reload 4, licensing submittals are also shown on this figure. The best-estimate FlBWR values agree with the vendor data points within about one percent. This slight variation is largely due to the difference between the FIBWR and Vendor's pressure' drop models which determine channel flow rates, and therefore the critical power ratio of the hot channel.

In order tc assure that the GEXL correlation had been correctly E

installed in the FIBVR code, CPRs were calculated by FIBWR for a number of channel conditions defined in reload 1.icensing submittals.

Data was obtained from both Brunswick Units and all channel types, and each of the channel conditions were explicitly input into a -

single-channel FIBWR model to test the correlation specifically.

The results, plotted on Figure 7, show an average ratio of 1.00, and -

a standard deviation of 0.5 percent, within round-off of the vendor-supplied data.

TABLE 5 FIBWR Comparison to Process Computer Core AP (psi) h FIBWR P1 FIBWR -

Unit Cycle  % Power  % Flow Core AP Core AP P1

- 1 1 72.45 100.61 21.45 21.98 -0.53 I 1 1 99.63 99.12 22.93 23.73 -0.80 1 1 61.82 94.92 19.35 19.74 -0.39 1 1 98.15 94.16 21.51 22.34 -0.83 1 1 50.70 79.61 14.67 15.25 -0.58

^

1 1 69.95 64.94 11.76 12.63 -0.87 1 1 55.25 50.52 8.44 9.17 -0.73 1 2 80.71 100.47 22.05 21.22 0.83 1 2 94.83 99.70 22.85 22.15 0.70 1 2 99.30 97.18 22.46 21.87 0.59 1 2 85.26 87.23 18.02 17.82 0.20 1 2 88.51 73.23 14.88 15.11 -0.23 f 1 2 76.35 57.57 10.76 10.94 -0.18 7 1 3 99.67 99.66 21.60 21.02 0.58

[e 1 3 99.14 93.83 20.80 20.11 0.69 1 3 59.56 92.33 20.45 20.03 0.42 1 3 82.04 73.43 13.71 13.65 0.06 2 1 3 S0.17 65.74 12.14 12.20 -0.06 4

1 3 63.01 50.74 8.74 8.94 -0.20 f

= 2 1 89.78 10G.C0 31.28 31.68 .40 4

2 1 93.11 94.45 29.03 29.12 .09 l 2 1 94.54 87.38 25.50 25.67 .17 5 2 1 59.65 77.81 20.05 20.53 .48 g

2 1 78.37 65.42 16.06 16.59 -.53 2 1 70.24 55.84 12.68 13.29 .61 p 2 1 41.75 45.58 9.17 9.51 .34 b 2 2 99.63 100.08 28.67 27.45 1.22

_ 2 2 94.09 94.23 25.95 24.78 1.17 y 2 2 64.66 74.29 17.18 16.73 0.45 2 2 67.41 64.29 13.99 13.80 0.19 2 2 56.61 53.48 10.74 10.72 0.02 2 2 18.75 42.60 8.04 8.31 -0.27 s

2 3 90.89 100.05 28.64 24.15 4.49 2 3 87.36 97.23 26.26 .'2.11 4.15 2 3 84.61 76.68 18.81 16.04 2.77

- 2 3 84.69 65.84 15.31 13.93 1.38 2 3 43.39 59.09 11.63 11.85 -0.22 e 2 3 64.29 49.35 9.86 9.17 0.69

=

0 2 4 81.44 99.43 27.01 25.76 1.25 2 4 87.89 92.26 24.41 23.52 0.89 6 2 4 77.59 85.98 21.48 20.70 0.78 e 2 4 74.34 77.95 18.42 18.03 0.39 2 4 74.63 63.17 13.74 13.83 -0.09 2 4 53.53 40.99 7.93 8.07 -0.14 E

b-

FIGURE 2 FIBWR COMPARISON TO PROCESS COMPUTER CORE AP 3 5--

P  :

R 30_

O  :

C -

E - 3 S 3 X S 25- 3

- x '

C - 0 x '

C

• 18f 3

M  :

P 2 0 -- /*

U -

/

T E

/

4 -

R 3 +

15 _

0

- 3

+

D P  :

1el -

x = 0.99 p +

S ' = 0.05 I 3 5

,.........,.......................... s s s s te is 2e 2s se 35 FIBWR CORE AP < PSI)

' a BSEP1 CYCLE!

• BSEP1 CYCLE 2 Ap process computer

+ BSEP1 CYCLES

• " a p riswR a BSEP2 CYCLE 1 4 BSEP2 CYCLE 2

+ BSEP2 CYCLES X BSEP2 CYCLE 4

TABLE 6 FIBWR Comparison to Measured AP (psi)

FIBWR Measured FIBWR -

% Power  % Flow CSP AP CSP AP Measured AP 74.28 100.00 16.14 16.02 0.12 99.68 99.66 16.87 17.12 -0.25 98.73 99.52 16.88 16.99 -0.11 99.14 99.41 16.76 16.92 -0.16 80.44 99.08 16.36 16.35 0.01

.77.77 99.08 16.18 16.27 -0.09 91.23 98.90 16.61 16.93 -0.32 99.54 97.62 16.'27 16.40 -0.13 95.59 96.56 16.00 15.82 0.18 92.28 95.43 16.19 16.95 -0.76 99.14 93.83 16.09 16.94 -0.85 94.53 92.62 14.75 15.00 -0.25

99.56 92.33 15.73 16.42 -0.54 97.09 90.73 14.31 14.81 -0.50 94.23 89.85 14.48 15.10 -0.62 94.51 88.68 14.19 14.92 -0.73 94.81 88.54 14.17 15.07 -0.90 92.35 70.27 11.17 12.27 -1.10 75.55 76.41 9.84 10.62 -0.78 82.04 73.43 8.91 10.29 -1.38 79.60 71.67 8.93 10.49 -1.56 73.14 68.07 7.82 8.68 -0.86 i

80.17 65.74 7.34 8.46 -1.12 76.23 64.24 7.01 8.25 -1.24 59.83 54.58 4.72 5.91 -1.19 63.01 50.74 4.03 5.46 -1.43 51.14 47.40 3.24 3.90 -0.66 50.20 44.16 2.56 4.18 -1.62 O CSP - Core Support Plate 5

/

FIGURE 3 FIBWR COMPARISON TO MEASURED AP l

20- -

es e

M 18- -

M

.E  : a A -

0 S 16-U - -

, g  : ga

e. _

D 1 4--

t C

S -

a

'p 12 _

m P -

g D i 1 0--

~

P

'S  : DD D

x - 1.06 I 8- -

a- 0.06 4

m 6- ,... ,....,....,.... ..

6 8 10 12 14 16 18 20 FISWR CSP AP CPSI) l 7, A P measured 6P FIBWR l

l l

l

TABLE 7 FIBWR Comparison to Process Computer (PC) Bypass Flow (Mlb/hr)

FIBWR PC FIBWR -

Unit Cycle  % Power  % Flow Bypass Leakage PC 1 1 72.45 100.61 7.33 8.90 -1.57 1 1 99.63 99.12 7.98 8.63 -0.65 1 1 61.82 94.92 6.72 8.25 -1.53 1 1 98.15 94.16 7.67 8.20 -0.53 1 1 50.70 79.61 5.34 6.63 -1.29

1. 1 69.95 64.94 4.51 5.05 -0.54 1 1 55.25 50.52 2.93 3.75 -0.82 1 2 80.71 100.47 8.28 8.30 -0.02 1 2 94.83 99.70 8.65 8.22 0.43 1 2 99.30 97.18 8.64 8.00 0.64 1 2 85.26 87.23 7.27 7.00 0.27 1 2 88.51 73.23 6.44 5.60 0.84 1 2 76.35 57.57 4.59 3.95 0.64 2 3 99.67 99.66 6.39 8.40 -0.01 1 3 49.14 93.83 8.3L 7.90 0.48 1 3 99.56 02.33 6.32 7.75 0.57 1 3 82.04 73.43 5.96 5.60 0.15

, 1 3 E0.17 65.74 5.39 5.05 0.34 1

1 3 53.01 50.74 3.67 3.40 0.27 2 1 89.75 105.08 5.08 5.30 -0.28 2 1 98.11 94.45 4.91 5.15 -0.24 2 1 94.54 87.38 4.49 4.68 -0.19 2 1 59.65 77.81 3.65 4.10 -0.45 2 1 78.37 65.42 3.19 3.25 -0.06 2 1 70.24 55.84 2.59 2.68 -0.09 2 1 41.75 45.58 1.72 2.05 -0.33 2 2 99.63 100.08 8.51 7.85 0.66 2 2 94.09 94.23 8.00 7.40 0.60 2 2 64.66 74.29 5.82 5.47 0.35 2 2 67.41 64.29 4.74 4.50 0.24 2 2 56.61 53.48 3.47 3.44 0.03 2 2 18.75 42.60 2.38 2.35 0.03 2 3 90.89 100.05 8.71 8.10 0.61 2 3 87.36 97.23 8.04 7.97 0.07 2 3 84.61 76.68 6.62 5.85 0.77 2 3 84.69 65.84 5.75 4.74 1.01 2 3 43.39 59.09 3.88 4.05 -0.17 2 3 64.29 49.35 3.43 3.05 0.38 2 4 81.44 99.43 8.34 8.40 -0.06 2 4 87.89 92.26 7.96 7.70 0.26 i 2 4 77.59 85.98 7.22 7.00 0.22 l

2 4 14.34 77.95 6.48 6.20 0.28 2 4 74.63 63.17 5.15 4.67 0.48 2 4 53.53 40.99 2.61 2.30 0.31

FIGbH 4 FIBWR CO}TARISON TO PROCESS C019 UTER BYPASS FLOW (MLB/HR) 9_ D

_- a

• ~

a a g x D' .

P 7-C l

1 a Si -

t

_. A g_ -

a a +  ;

A X +

_ t 42--

4+ c D

4 o +

S__

X g ic = 1.00 i .

_ a = 0.11 1-l 1 2 3 4 5 6 7 8 9 FIBWR BYPASS FLOW CMLB/HR)

, a BSEP1 CYCLE!

• BSEP1 CYCLE 2 BYPASS FLOW (pc) o BSEP1 CYCLES BYPASS FLCW (FIBWR)

A BSEP2 CYCLE 1

+ BSEP2 CYCLE 2

+ BSEP2 CYCLES X BSEP2 CYCLE 4

FIGURE 5A

........... BlBOLE FLOW RATES (1000 LBM/HR)

129A : BRUNSWICK 2 CYCLE 4 3/11/82 0 129.2 : 83.13% PCWER

0.2  : 98.99 FLOW

134,5 : 127.8 :

D: 136.2 : 128.6 :

-1. 7 : -0. 8 :

s.........:.........:..........

127.7 : 133.2 : 124.6 :

e : 127.4 : 135.0 : 125.3 :

0. 3 : -1.8  : -4.7  :

, t.........:.........:.........:..........

126.9 : 125.7 131.4 : 172.6 :

a- 125d : 125.9 : 133.6 : 123.2 :

l  : 0.5 : -0. 2 : -2.2 : 46 :

1&1 : 125.5 122.8 : 128.8 : 122.3 :

18 111 : 125.7 124.4 : 131.9 : 122.1 : ,

a t.0  : -0. 2 -1. 6 : -3.1  : -0.1  : .#

se........:.........:.........eM4+##M M.........:..........

138.6 : 125.5 : 129.9 a 121.1 e 129.6 : 121.9 :

16 138.8 : 125.8 : 132.7 e 123.0

• 131.8 : 122.3 :

-9. 2 : -0. 2 : -2.8 e -1. 9 e -2.2  : -0. 4 :

.........:.........:.........et M******+.........:.........:..........

134,3 : 1&1 : 125.5 : 124.9 : 123.1 : 124.2 : 125.0 :

h: 133.4 : 125.6 : 125.0 : 124.4 : 123.3 : 124.6 : 125.0 :

0.9  : 0.5  : 0.5  : 0.5  : -0. 2 : -0. 4 : 2.3  :

132.9 : 125.1 : 132.1 : 125.1 : 131.0 : 127.1 : 129.7 : 128.3 :

[2 : 134.4 : 124.9 : 133.7 : 124.9 : 133.1 : 128.7 : 129.7 : 128.3 ::

-1. 6 :

-1.5 0.2 1 -1. 6 : 0.2  : -2.1  : 0. 0 0.0

.  : 122.0 : 122.6 : 123.1 : 123.3 : 125.4 : 129.3 : 130.6 : 130.6 : 135.1 :

Et 122.2 : 122.9 : 122.9 : 123.3 : 125.5 : 129.6 : 131.9 : 130.3 : 135.2 :

-0. 2 : -0. 3 : 0.2  : 0. 0 : -0.1  : -0. 3 : -1.3  : 0.3  : -0.1  :

122.8 121.8 : 123.5 : 124.2 : 127.0 : 128.7 : 132.0 133.5 : 137.6 : 75.3 :

p i  :

123.1

-0. 3 :

122.1 : 123.2 : 124.2 : 126.6 : 129.0 : 132.2 : 133.7

-0. 3 : 0.3  : 0.0 0.4  : -0. 3 : -0. 2 : -0. 2 137.4 : 75.1 :

0.2 0. 2 :

I 123.4 : 124.8 : 126.2 : 127.8 : 132.4 : 139.8 : 75.1 : 75.4 : 75.7 :

p i 122.7 123.7 : 125.3 : !&5 : 131.8 : 139.8 : 74.9 : 75.1 : 75.6 :

0.7  : 1.1  : 0.9 : 1.3  : 0.6  : 0.0 0.2  : 0.3 0.1  :

l .........:.........:.........:.........:..................:.........:.........:.........: ...........

!  : 127.8 : 127.5 : 130.4 : 131.6 : 136.5 : 75.1 : FIBWR :

D 1&1 : 126.3 : 128.8 : 130.1 : 135.8 : 74.9 :  : PC

.a l  : 1.7 1.2  : 1.6  : 1.5  : 0.7  : 0.2  :  :

I l  : 74,5 : 74.2 : 74.9 : 75.2 : 75.6 :

[3 74.3 0.2 :

72.8  :

1. 4 :

74.7 0.2

75.0 0.2 75.6 0.0

RMS DIFF.=1.00

.........:.........:.........:.........:.........: e HOT CHAMEL 27 29 31 33 35 37 39 41 43 45 1

FIGURE 5B

........... BLMDLE FLCW RATES (1000 LBM/HR)

50.4 : BRUNSWICK 2 CYCLE 4 12/21/88 D: 51.8 : 49.73% POWER

-1.4 : 38.83% FLOW

.  : 25.0 : 51.0 54 : 56.6 : 52.2 :

-1.6 : -1. 2 :

52.9 : 53.2 : 47.4  :

22 53.8 : 55.7 : 48.7 : ,

s -0. 9 : -2.5  : -1. 3 3

49,6 : 50.3

• 50.7

• 47.9 :

it 51.0 : 51.3 e 53.7 e 49.0 :

-1. 4 -1. 0 * -3. 0 * -1.1  :

s e . . . . . . . . l . . . . . . . . 9684 f+##+#4. . . . . . . . . : . . . . . . . . . .

6923 : 47.8 49.f.  : 51.8 48.1  :

18 5J.1 : 49.4  : W.4 54.6 : 48.9  :

-0. 8 : -1.6  : 4.9  : -2.8 : -0. 8 :

55.3 : 51.1  : 52.5 : 53.2 : 54.7 : 49.3 :

16 56.3 : 51.1  : 55.3 4 54.3 56.6 : 50.2 :

-1.8 : -1. 0 -2.8 : -1.1 -1.9 : -0. 9 :

53.3 49.2 : 50.5 : 52.8 : 52.1 : 49.1 : 46.5 :

14 : 54,2 : 59.5 : !!.? : f4.0 5'.9 : 54.4 : 49.3 :

1 -0. 5 : -1. 3 : -4.7 : -1. 2 -9. 8 : -!.3  : 47 :

.........:.........f.........:.........:.........:.........:......... ..........

53.0 50. 4 : 53.7 : 51.5 : 53.2 : 58.6 : 48.3 : 49.7 12 55.7 : 51.3 : 56.3 : 52.4 55.8 : 51.4 49.5 : 50.4 :

-2.7 : -0. 9 : -2.6 : -0. 9 : -2.6 : -0. 8 : -1.2  : -0. 7 :

4949 : 49.1  : 49.4  : 49.1  : 59.5 : 49.6 : 50.0 50.2 : 52.5 :

10 : 50.6 : 50.4  : 50.0 50.4  : 51.3 : 50.8 : 58.7 : 51.4 : 53.2 :

-0. 7 : -1.3  : -0. 6 : -1. 3 : -0. 8 : -1. 2 : -0. 7 : - 1. 2 : -0. 7 :

.........:......... .........:.........:.........:.........!.........:.........:.........:...~......

4  : 52.8 : 50.9 : 49.4 : 51.6 : 50.6 : 51.7 : 51.6 : 54.1 : 54.6 : 36.6 :

C3 : 500 : 51.8 : 50.7 : 52.6 : 51.9 : 52.6 : 52.4 55.4 : 55.7 : 32.9 :

-1. 2 -0.9 : -1.3  : -1. 0 -1. 3 : -0. 9 : -0. 8 : -1.3  : -1.1  : 2.7 :

54.4 : 51.1 : 51.2 : 51.6 : 54.0 : 55.4 : 35.2 34.1  : 32.8 :

06 : 55.7 : 52.2 : 51.9 : 52.9 : 55.3 : 57.3 : 33.0 32.5 : 32.6 :

-1. 3 : -1.1  : -0.7  : -1. 3 -1. 3 : -1. 9 : 2.2 1.6  : 0.2  :

FIBWR :

52.5 : 53.2 : 52.6 : 53.5 54.6 : 35.1  :

94 53.9 : 54.1 : 53.5 : 54.8 : 55.7 : 32.6 :  : PC  :

-1. 4 : -0. 9 : -0. 9 : -1. 3 : -1.1 : 2.5  : :A  :

35.2 : 35.6 : 34.9  : 34.5 33.6 :

82 a 33.0 32.3 : 33.0 32.7 33.0 : RMS DIFF.=1.51

2.2 3.3  : 1.9 1. 8  : 0.6  :

I

.........:.........:.........:.........:.........: 45

• HOT CHAM E.

27 29 31 33 35 37 39 41 43 l -

FIGURE SC

........... BLMDLE FLOW RATES (1000 LBM/HR)

134.1 : BRIESWICK 1 CYCLE 3 2/01/82

$3 : 135;2 : 98.985 PCWER

-1.1  :  % 82% FLCW

132.5 : 129.1 :

14 : 133.9 : 130.4 :

-1. 4 : -1.3  :

123,1 : 125.3 118.7 22 : 125.1 : 127.0 : 121.1 :

-2. 0 : -2. 0 : -2.4  :

123.7 121.8 121.4 : 119.0 20 125,7 123.3 : 124.2 : 129.7 :

-2. 0 : -1. 5 : -2.8  : -1. 7 :

11 % 7 : 121.9 : 116.9 : 119.4 : :23.6 :

18 : 121.4 : 124.8 : 128.6 : 122.7 125.1 :

-1.7 : -2.9 : -3.7 : -3. J : -3.1 :

.........:........ 4.........:......... .........:..........

121.7 120.6 : 119.9 : 116.9 : 125.8 : 125.6 :

16 : 124,4 : 122.5 : 123.1 : 113.6 : 128.5 : 123.5 :

-2.7 : -1. 7 : -3.2 -1.7 : -1. 7 : -2.1 :

. . . . . . . . : . . . . . . . . . . . . . . . . . 8. . . . . . . . . i . . . . . . . . . : . . . . . . . . . H et e MH H 129.2 : 122.9 : 125.9 : 123.1 : 229.8 : 123.8 e 116.6 e 14 : 122.4 : 124.4 : 127.5 : 12?.4 : 122.3 : 124.9 e* 119.1 e

-2.2  : -1. 6 : -1. 6 : -1. 3 : -1. 5 : -1.1 -1. 5 e f.........:..................i.....-............:.........HHMH#H..........

125.8 : 132.8 : 137.9 : 128.0 : 125.8 : 124.8 : 123.8 : 118.8 :

12 : 127.9 : 133.7 : 137.7 : 128.6 : 127.4 : 127.1 : 126.2 : 120.1 :

-2.1 : -0. 9 : 0.2 : -0. 6 : -1. 6 : -2.3  : -2.4  : -1.3  :

127.7 : 138.0 : 131.4 : 125.0 : 121.8 : 126.5 : 122.1 : 124.3 : 129.3 :

-10 129,3 : 138.2 : 133.2 : 125.9 : 123.3 : 128.2 : 124.6 : 125.4 : 130.2 :

-1. 6 : -0. 2 : -1.8  : -0. 9 : -1. 5 : -1.7  : -2.5  : -1.1  : -0. 9 :

131.1 : 129.2 : 127.2 : 123.3 : 127.8 : 125.4 : 125.0 : 126.1 : 135.1 : 66.6 :

O: 131.7 129.8 : 128.6 : 124.6 : 129.2 : 126.9 : 126.2 : 127.6 : 135.2 : 66.3 :

-0. 6 : -0. 6 : -1. 4 : -1.3  : -1. 4 : -1. 5 : -1.2 -1.5 : -0.1 : 0.3 :

125.9 : 127.5 : 125.2 : 126.9 : 128.1 : 131.0 66.5 : 67.1 : 68.0 :

O 126.7 127.8 : 126.1 : 127.2 : 129.2 : 131.4 : 66.2 : 0.4 66.7: : 67.6  ::

-0. 8 : -0. 3 -0.9 : -0.3 : -1.1 : -0.4 : 0.3 : 0.4

FIBWR :

131.3 : 131.0 : 131.8 : 131.0 : 135.7 : 66.2 :  : PC  :

94 : 1131.1 : 130.8 : 131.6 : 131.3 : 135.7 : 66.0 :

0.2 0. 2 0.2  : -0. 3 0.0 0.2  : 6  :

67.2 67.2 : 67.4 : 67.5 : 68.2 :

C2 : 66.7 : 66.7 : 66.9 : 67.0 :: 67.9 0.3

RMS DIFF.=1.58

0.5  : 0.5  : 0.5  : 0.5

.........:..................:.........:.........: 35 37 39 41 43 45

• HOT CHAMEL 27 29 31 33

- - - - -- .,n- , -- , . . - -

FIGURE 5D

........... BLMDLE FLOW RATES (1000 LBM/HR)

60.9 : BRUNSWICK 1 CYCLE 3 9/27/81 9: 61.7 : 54.385 POWER

-0. 8 : 44.68% FLOW

62.4 : 60.2

$4 : 64;0 61.1  :

-1. 6 : -0. 9 :

63.3 : 59.6 : 58.7 :

3: 64.2  : 60.7 : 60.1

-1. 2 : -1.1 : -1. t

59,2 : 58.5 58.8 : 58.3 :

29 : C.4 : 59.'i  : 59.4 : 39.4 :

-L. 3 -1. 0 -1. 4 : -1.1  :

.........:.....s...:.........!.........:..........

58.8 : 57.8 : 57.4 27.9 : 59.2 :

18 : 59,2 53.2 : 59.2 : 59.3 : 62.5 :

-1.2 : - 1. 4 : -1. 8 : -1.4 : -1.3 :

6!.5 : 57.3 : 57.8 : 61.4 : 51.9 54.8  :

16 : H.4 : 59.0 : 59.2 : E2.0 52.9 : 60.2 .-

3.5: -1.2 -1.4 t 0. 6 : -1.0 : -1. 2 :

61.8 : 57.5 : 53.2 : 61.4 : E2.2 : !8.6 : 55.3 :

'14 (3.8 * : "8.

. 7 : 59.7 : 62.4 : 53.3 : 59.6 : 58.0 .:

-1. 2 : -1. 2 : -1.5 : -1. 0 : -1.1 : -1. 0 : -1. 7 :

57.6 : 56.7 : 57.8 : 57.9 : 58.6 : 58.1  : 56.5 : 56.7 12 : 59 2 : 58.1 59.3 : 59.1 : 59.8 : 59.5 : 58.1 : 58.3 :

-1. 6 : -1. 4 : -1.5  : -1. 2 : -1.2  : -1. 4 : -1. 6 : -1. 6 :

s........:........ 9##########......... .........:.........:.........:.........:..........

58.1 : 57.8 e 55.6

• 56.8 : 56.8 : 57.2 : 56.2 : 57.4 : 60.7 :

10 59,8 : 59.3

• 57.6 e 58.6 : 58.6 : 58.5 : 57.9 : 58.5 : 61.8 :

-1. 7 : -1. 5 * -2. 0 * -1. 8 : -1. 8 : -1. 3 : -1. 7 : -1.1 : -1.1 :

.........:.........fe#########.........:.........s.........:......... ......... .........:..........

61.5 58.3 : 57.2 : 59.7 : 60.1 : 58.6 : 57.3 58.6 : 62.2 : 36.1  :

C3 62.6 : 59.5 : 58.9 : 51.5 : 61.3 : 60.1  : 58.5 : 59.9 : 62.8 : 33.5 :

-1.1 : -1. 2 : -1.7 : -1. 8 : -1.2 : -1. 5 : - 1. 2 : -1.3 : -0. 6 2. 6 :

62.8 : 60.0 : 59.2 : 61.3 : 62.5 : 51.5 : 36.1 35.9 : 35.3 :

^3  : 64.0 : 61.1 : 60.8 : 62.4 : 63.4 : 62.3 33.4 33.4 : 33.6 :

-1.2 : -1.1  : -1. 6 : -1.1  : -1.1  : -9. 8 2. 7  : 2.5  : 1.7  :

61.8 : 61.4 : 61.2 : 61.8 : 53.0 : 36.1  :  : FIBWR :

84 : 62.5 : 62.1  : 61.9 : 62.8 : 63.7 : 33.2 : PC  :

-0. 7 : -0. 7 : -0.7 : -1. 0 : -0. 7 : 2. 9  : :A  :

3630 36.0 : 35.5 : 35.3 : 34.3 :

82 : 33.2 : 33.2 : 33.2 : 33.1 : 33.2 : R*S DIFF.=1.58

2. 8 : 2. 8 2.3  : 2. 2  : 1.1  :

\ 2.........:..................:.........:.........: + 60T CHM NEL 27 29 31 33 35 37 39 41 43 45

+

D

-.-w

. FIGURE 6 Brunswick 2 C CriticalPowerRatio(GkXLfcle5 vs. Bundle Power FIBWR Hot Channel Analysis

1. CS :

1 . 4 E-3.

i \

1 . 4a." _

FIBWR 3

• VdNDOR 1.CEi -

3 e

~

1.Ca *

=

\ *

1. GE ~

e

e

1. Ce-2

• 1.15" 1.1 e-E

1. C5-5 i.

1. Ce " . . . . . . .- .

E.Em E.7E s.se e.2E e.Em s.7E 7.ee 7.2E suNDLE PcWER CMWT3

, FIGURE 7 FIBWR Comparison to Vendor Critical Power Ratio 1.SS-

. A

. as

. A

, i t.sm- a A

. AA

~

/

. E t . 20-

. e

. i

. 8

- AA

' ~

As " l 00 t.=S a

$ a # = 0.00 5

. 85 l .

1 .

1.tC- .

1.15 1.38 1.25 1.38 1.35 CRZTZCAL POWER MATIC CFZ5WR) i CPR vendor O 7x7

%=

• 8x8 CPR FIBWR a 8x8R

4.0 Summarv and Conclusions A CP&L model of the FIBWR code was developed to perform steady-state thermal . hydraulic simulations of the Brunswick plant. A series of verifications to vendor models and measured data was dcne to evaluate the capability of the code to be used for its intended applications.

The ability of the CL FIEWR model to calculate pressure drops was demonstrated by comparisons to the Brunswick Units 1 and 2 process computer P1 cdits. This comparison verified the accuracy of FIBWR i

results to both the process computer calculated plenum to plenum pressure drop, and to the measured core support plate pressure drop.

The FIBWR code has been shown to accurately predict BWR flow distribu-tions between active channels and between tha active and bypass regions.

In a comparison to process computer bundle flow rates as a function of bundle power, FIBWR predicted the channel flow distributions to within 1.5 percent of the process computer values. Bypass flow rates calculated by FIBWR agreed well with the bypass / total flow relationship developed from the process -computer databook for the same core power and flow conditions. FIBWR differed, as expected, from the process computer bypass relationship for conditions where this relationship did not apply.

L A comparison of vendor critical power ratiop data with FIEWR results has i

demonstrated that the GEXL CPR correlation has been properly installed in the FIBWR code. A hot bundle CPR analysis was performed using this

(

correlation in FIBWR to verify good agreement with vendor-calculated,

limiting-bundle powers for given critical power ratios.

The CP&L FIBWR model has been shown to accurately calculate pressura.

drops, flow distributions, and critical power ratios for steady-state thermal-hydraulic applications to the Brunswick nuclear plant.

103 I

i e

5.0 REFERENCES

(1) Vermont Yankea. Nuclear Power Corporation; " Methods for the Analysis of Boiling Water Reactors, Steady-State Core Flow Distribution Code (FIBWR);" YAEC-1234; December 31, 1980.

(2) Letter from Domenick B. Vassallo, Chief of Operating Reactors Branch No. 2, to J. B. Sinclair; Vermont Yankee Nuclear Power Corporation; September 15, 1982.

(3) EPRI; "FIBWR: A Steady-State Core Flow Distribution Code for Boiling Water Reactors;" NP-1923; July 1981.

(4) General Electric Company; " Brunswick Steam Electric Plant Units 1 and 2, -

Reload Fuel Supply and Related Services, Technical Description;"

Volume 11, Part 1; July 25, 1979; Pages 3-17. (GE Proprietary)

(5) Letter free J. E. Craven, General E3cetric Company, to L. H. Martin, Carolina Po ter & Light Company;

Subject:

CP&L Reload Fuel Proposal Technical Information; February 25, 1982. (GE Proprietary)

(6) General Electric Company; " Brunswick Steau Electric PIant tinit 1 Safety Ar.alysic Eeport for Plant Modifications to Eliminate Significant In-Coro Vihretions: NEDC-21215; Harch 1976; Section 4.2.3. (GE Proprietary)

(7) General Electric Ccmpany; "Genarcl Electric Standard Application for Reactor Fuel (United States Supplement);" NEDE-24011-F-A-4-US; January 1982; US.B-103. (GE Proprietary)

(8) R. T. Lahey and F. J. Moody; " Thermal Hydraulics of a Boiling Water Nuclear Reactor;" American Nuclear Society; 1973; Page 242.

(9) G. S. Lellouche and B. A. Zolocar; " Mechanistic Model for Predicting Two-Phase Void Fraction for Water in Vertical Tubes, Channels, and Rod BundI:s;" EPRI NP-2246-SR; February 1982.

(10) EPRI; " Low-Flow Stability Tests at Peach Bottom Atomic Power Station Unit 2 During Cycle 3;" NP-972; April 1981; Pages 3-1 and 3-3.

l l (11) General Electric Company; "GEXL Correlation Application to BWR/2-6 l

Reactors;" NEDE-25422. (GE Proprietary) 106 I

l

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