ML20100G573
| ML20100G573 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 02/15/1996 |
| From: | Mcintyre B WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| To: | Quay T NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML19355C684 | List: |
| References | |
| AW-96-927, NUDOCS 9602230258 | |
| Download: ML20100G573 (38) | |
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Westinghouse Energy Systems Ba 355 Pittsburgh Pennsylvania 15230-0355 Electric Corporation AW-%-927 February 15,1996
- Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555 t
ATTENTION: T.R. QUAY APPLICATION FOR WITHHOLDING PROPRIETARY i
INFORMATION FROM PUBLIC DISCLOSURE
SUBJECT:
CONSERVATISM IN MODELING OF THE PCS FILM IN THE DBA i EVALUATION MODEL AND COMPARISON OF THE RANGE OF FILMS PARAMETERS IN THE PCS TEST DATA WITH AP600
Dear Mr. Quay:
i The application for withholding is submitted by Westinghouse Electric Corporation (" Westinghouse")
pursuant to the provisions of paragraph (b)(1) of Section 2.790 of the Commission's regulations. It contains commercial strategic information proprietary to Westinghouse and customarily held in confidence.
The proprietary material for which withholding is being requested is identified in the proprietary i version of the subject report. In conformance with 10CFR Section 2.790, Affidavit AW-96-927 l accompanies this application for withholding setting forth the basis on which the identified proprietary i information may be withheld from public disclosure.
Accordingly, it is respectfully requested that the subject information which is proprietary to Westinghouse be withheld from public disclosure in accordance with 10CFR Section 2.790 of the .
Commission's regulations.
Correspondence with respect to this application for withholding or the accompanying affidavit should ,
reference AW-%-927 and should be addressed to the undersigned.
Very ly yours, Bria Intyre, Ma 'er Advanced Plant Safety and Licensing
/nja cc: Kevin Bohrer NRC 12HS 2683A 9602230258 960215 PDR- ADOCK 05200003 A PDR l
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AW-96-927 AFFIDAVIT [
i COMMONWEALTH OF PENNSYLVANIA:
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COUNTY OF ALLEGHENY: t Before me, the undersigned authority, personally appeared Nicholas J. Liparulo, who, being by me duly sworn according to law, deposes and says that he is authorized to execute this Affidavit on behalf of. Westinghouse Electric Corporation (" Westinghouse") and that the averments of fact set forth l in this Affidavit are true and correct to the test of his knowledge, information, and belief, i i
f '
L.
g Nicholas J. Lipa 1 Manager Regulatory and Engineering Networks Sworn to and subscribed before me this / day l of J.I+e asM ,1996 8w/bd r Notary Public N&c! %!
RosoMaria Pera ?Wy Pub 5c MonroaaEa Batc. . ..jry Crianty ,
M/ Commiston E); min 4,199G 2mA Member, Pennsytyma/sooanon at Notanes ,
AW-96-927 ,
l (1) I am Manager, Regulatory and Engineering Networks, in the Nuclear Services Division, of the Westinghouse Electric Corporation and as such, I have been specifically delegated the function of reviewing the proprietary information sought to be withheld from public disclosure in connection with nuclear power plant licensing and rulemaking proceedings, and am authorized to apply for its withholding on behalf of the Westinghouse Energy Systems Business Unit.
l (2) I am making this Affidavit in conformance with the provisions of 10CFR Section 2.790 of the Commission's regulations and in conjunction with the Westinghouse application for withholding accompanying this Affidavit.
(3) I have personal knowledge of the criteria and procedures utilized by the Westinghouse Energy-Systems Business Unit in designating information as a trade secret, privileged or as confidential commercial or financial information.
(4) Pursuant to the provisions of paragraph (b)(4) of Section 2.790 of the Commission's regulations, the following is furnished for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld.
(i) The information sought to be withheld from public disclosure is owned and has been held in confidence by Westinghouse.
(ii) The information is of a type customarily held in confidence by Westinghouse and not customarily disclosed to the public. Westinghouse has a rational basis for determining the types of information customarily held in confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain types of information in confidence. The application of that system and the substance of that system constitutes Westinghouse policy and provides the rational basis required.
Under that system, information is held in confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential competitive advantage, as follows:
2684A
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AW-96-927 :
(a) The information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.) where prevention of its use by any of Westinghouse's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies.
(b) It consists of supporting data, including test data, relative to a process (or !
component, structure, tool, method, etc.), the application of which data t secures a competitive economic advantage, e.g., by optimization or improved marketability.
(c) Its use by a competitor would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.
(d) It reveals cost or price information, production capacities, budget levels, or commercial strategies of Westinghouse, its customers or suppliers.
(e) It reveals aspects of past, present, or future Westinghouse or customer funded development plans and programs of potential commercial value to Westinghouse.
1 (f) It contains patentable ideas, for which patent protection may be desirable.
There are sound policy reasons behind the Westinghouse system which include the following:
(a) The use of such information by Westinghouse gives Westinghouse a competitive advantage over its competitors. It is, therefore, withheld from disclosure to protect the Westinghouse competitive position.
(b) It is information which is marketable in many ways. The extent to which such information is available to competitors diminishes the Westinghouse ability to sell products and services involving the use of the information.
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. . . ~ . ... - . - - - _. - . ... - - - - - . . . . ~ - - . . - - . _-
F AW-%-927 I (c) Use by our competitor would put Westinghouse at a competitive disadvantage j
- by reducing his expenditure of resources at our expense. [
f (d) Each component of proprietary information pertinent to a particular l competitive advantage is potentially as valuable as the total competitive j advantage. If competitors acquire components of proprietary information, any ;
one component may be the key to the entire puzzle, thereby depriving l Westinghouse of a competitive advantage. j
, (e) Unrestricted disclosure would jeopardize the position of prominence of Westinghouse in the world market, and thereby give a market advantage to the competition of those countries.
l (f) The Westinghouse capacity to invest corporate assets in research and i development depends upon the success in obtaining and maintaining a competitive advantage.
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(iii) ' The information is being transmitted to the Commission in confidence and, under the l provisions of 10CFR Section 2 72, it is to be received in confidence by the Commission.
(iv) The information sought to be protected is not available in public sources or available ;
information has not been previously employed in the same original manner or method to the best of our knowledge and belief.
(v) Enclosed is Letter NSD-NRC-%-4646, February 15,1996 being transmitted by l Westinghouse Electric Corporation (E) letter and Application for Withholding l
Proprietary Information from Public Disclosure, Brian A. McIntyre (E), to Mr. T. R. Quay, Office of NRR. The proprietary information as submitted for use by Westinghouse Electric Corporation is in response to questions concerning the AP600 plant and the associated design certification application and is expected to be applicable in other licensee submittals in response to certain NRC requirements for justification of licensing advanced nuclear power plant designs.
2684A
_ . _ . _ - . ~ . _ _ _ _ . . _ _ _ _ . . _ _ . _ _ . _ . _
AW-%-927 This information is part of that which will enable Westinghouse to:
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(a) Demonstrate the design and safety of the AP600 Passive Safety Systems. !
(b) Establish applicable verification testing methods. !
[
t (c) Design Advanced Nuclear Power Plants that meet NRC requirements. l i
(d) Establish technical and licensing approaches for the AP600 that will ultimately result in a certified design. ;
t (e) Assist customers in obtaining NRC approval for future plants. !
i, Further this information has substantial commercial value as follows: j (a) Westinghouse plans to sell the use of similar information to its customers for r
purposes of meeting NRC requirements for advanced plant licenses, I
(b) Westinghouse can sell support and defense of the technology to its customers l in the licensing orocess. t l
Public disclosure of this proprietary informetion is likely to cause substantial harm to .
l I
the competitive position of Westinghouse because it would enhance the ability of competitors to provide similar advanced nuclear power designs and licensing defense services for commercial power reactors without commensurate expenses. Also, public disclosure of the information would enable others to use the information to meet NRC j requirements for licensing documentation without purchasing the right to use the j l
information.
l l
i 2nMA
AW-96-927 The development of the technology described in part by the information is the result of applying the results of many years of experience in an intensive Westinghouse effort and the expenditure of a considerable sum of money.
In order for competitors of Westinghouse to duplicate this information, similar l technical programs would have to be performed and a significant manpower effort, having the requisite talent and experience, would have to be expended for developing analytical methods and receiving NRC approval for those methods.
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Further the deponent sayeth not.
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ENCLOSURE 2 l NSD-NRC 96-4646 i
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- 26AJA .
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, Westinghouse Proprietary Class 3
.. Preliminary 1
. l Conservatism in Modeling of the PCS Film in the DBA Evaluation Model and l Comparison of the Range of Film Parameters in the PCS Test Data with AP600 ;
February 15,1996 R. P. Ofstun J
i l
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Westinghouse Proprietary Class 3 Preliminary Summary The conservatism in the modeling of th,e evaporating film in the DBA evaluation model is examined in this report. An assumed 660 second delay in application of the PCS film in the DBA evaluation model is the sum of the maximum 53 second delay to establish the film flow plus an additional 10 minute delay to establish steady state film coverage, as measured in the Water Distribution Tests. The assumed delay conservatively neglects a minimum of 350,000 BTUs of heat removal during the 10 minute period needed to establish a steady state film coverage.
The expected AP600 shell temperature response during the 10 minute time period to establish steady state coverage is estimated. At the actual time of initiation of PCS flow rate to the shell surface (less than 60 seconds after initiation of the DBA event), the external surface temperature will have increased by less than 10*F. The dry, extemal shell surface temperature will have increased by less than 50*F at the time the first weir fills and begins to spill and by less than 70*F at the time the second weir fills and begins to spill. Tests run during the PCS testing program verified the ability of the water film to wet and rewet a hot surface (temperature exceeding 240*F) coated with the inorganic zinc compound to be used on the AP600 containment shell.
The range of the PCS film coverage test data parameters is tabulated and compared with the expected range for the AP600. With the exception of the maximum evaporating film temperature and maximum sidewall Ren. number, the test data bounds the expected range of the AP600 film parameters. It is more important to bound the lower expected film temperature with the test data, than the higher expected film temperature since the film is less stable at lower film temperatures.
Also, it is more important for the tests to bound the minimum sidewall Re n for evaluating the film stability model. Therefore, even though the test data does not bound the expected maximum film temperature or maximum Ren , the ranges are sufficient for evaluating the Zuber-Staub film .
stability model.
The method used to determine the bounding margin value for the Zuber-Staub film stability model is described. He margin value obtained by this method bounds data from the unheated Water Distribution Tests and the heated baseline and Phase 2 Large Scale Tests.
The sensitivity'of the Zuber-Staub film stability model to wetting angle, film temperature and heat flux is presented. He minimum stable film flow rate predicted by the Zuber-Staub model decreases with increasing film temperature and increases with wetting angle. De minimum stable film flow rate becomes less sensitive to heat flux as the assumed wetting angle increases and is relatively constant for heat flux less than 10000 BTU /hr-ft 2at wetting angles greater than 20'.
A sample calculation for the applied PCS film flow rate input to the DBA evaluation model is provided to show how the Zuber-Staub film stability model is used to create a conservative film input flow rate for the DBA evaluation model, as described in Ref 11.
1
.~ . . __. - _
- Westinghouse Proprietary Class 3
. Preliminary Introduction s
A large portion of the energy released to containment following a postulated accident in the AP600 is removed by evaporation of an' applied water film from the outer containment shell i surface. Several questions have been raised on the level of conservatism in the DBA modeling assumptions related to the coverage and stability of the evaporating film. The purpose of this report is to address questions related to:
- 1. The conservatism in the DBA evaluation model assumed time delay for application of the i PCS film;
- 2. A comparison of the range of film coverage parameters for the PCS tests with the range expected for AP600
- 3. The method used to determine a conservative, bounding margin value (1%) for the Zuber-Staub film stability model;
- 4. The method used to determine a conservative, bounding minimum applied PCS flow rate for the DBA evaluation model.
Conservatism in the Assumed Time Delay for Application of the PCS Film in the DBA Evaluation Model The Water Distribution Tests were used to test the ability of various weir designs to cover a large fraction of the containment shell with water and to estimate the time to establish steady state film coverage on the AP600. A full scale test section representing a 1/8 sector of the containment dome was built. Based on a review of the video tapes for the phase 3 (improved weir design) water distribution tests, the time to fill and begin to spill over the first weir with a flow rate of 27.5 gpm (equivalent to 220 gpm flow rate on AP600) was estimated to be about 2.5 minutes, the time to fill and begin to spill over the second weir was estimated to be about 5 minutes, and the total time to establish steady state coverage of the dome and sidewall was estimated to be about 10 minutes.
The maximum time for water to begin flowing onto the shell surface, following a postulated event that actuates the PCS, is 53 seconds and is based on a maximum 20 second valve stroke time plus 30 seconds to fill the pipes and 3 seconds to fill the bucket. Therefore, for the DBA evaluation model, steady state film coverage is conservatively assumed to occur at 11 minutes after event initiation. The 11 minute coverage delay time assumed in the DBA model is conservative in that it neglects energy removal from the shell while steady state film coverage is being developed. An assessment of the amount of conservatism in the predicted energy removal is provided in the calculations that follow.
2
1 Westinghouse Proprietary Class 3 Preliminary Wall Temperature and Heat Removal Calculations q The time for the dry outer shell to reach a given temperature can be tabulated as a function of the internal energy transfer coefficient using the properties of the [ ]" steel shell and i Figure 4-8 from Kreith (Ref.1). The initial shell temperature will be assumed to be 120*F and I the time for the outer shell to reach the boiling point for water (212*F) will be calculated with j the following input: ;
T = 212*F Ti = 120*F l T., = 250*F l
{ = (T - T )/(T i - T ) = 0.292 k, = 25 BTU /hr-ft-F L =[ ]" ft !
a 2
= 0.49 ft /hr Msume the internal energy transfer coefficient (condensation in air) is much larger than the externd heat transfer coefficient (forced convection) such that the dry outer shell surface can be considered adiabatic (insulated) over the time period of interest. This assumption should lead to a minimum value for the time to reach 212*F. The results of the calculation are tabulated below.
l 2 2 U (BTU /hr-ft -F) 1/Bi at/L t (seconds) 5 34.3 43 5792 10 17.1 23 2%3 50 3.43 $ 673 100 1.71 2.6 350 Based on previous calculations assuming perfect mixing inside containment, the average internal 2
energy transfer coefficient is expected to be around 60 BTU /hr-ft-F. The transient value in steam rich regions (if the containment stratifies quickly) could be higher, and a 25-50% increase is not unreasonable. Therefore, the time for the dry outer containment shell temperature to reach the boiling point following a LOCA event is estimated to be between 400 and 600 seconds.
I A WGOTHIC AP600 model was run for comparison with the hand calculations. The calculated temperatures at the top of the dome, before application of the PCS film, are shown in Figure 1.
The WGOTHIC calculation of the time for the shell surface temperature on top of the dome to reach 212*F (about 450 seconds) agrees reasonably well with the estimate above. The heatup rate 2
is about 0.2*F/sec and falls between the 50 and 100 BTU /hr-ft-F internal energy transfer coefficient values assumed in the hand calculation. During the 10 minute transient time after the initial blowdown, the containment temperature (and therefore the maximum possible internal shell temperature) is limited to about 260*F by condensation on the heat sinks inside containment.
3
Westinghouse Proprietary Class 3 Preliminary Assuming the maximum delay in application of water to the dome (53 seconds), the outer shell temperature will have increased by less than 10*F at the time water is first applied at the top of the dome. Using a nominal 33 second application delay time and the weir fill times determined in the phase 3 Water Distribution Tests with the 220 gpm PCS flow rate (based on the single failure criteria), the temperature of the dry ponion of the outer shell will have increased by less than 50*F at the time the first weir begins to spill (about 183 seconds) and less than 70*F at the time the second weir begins to spill (about 333 seconds). Therefore, the sidewall temperature will be less than 200*F at the time the water film begins to advance down the vertical surface.
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Containment Atmosphere + 1nside Shell Surface
+ OutsIde 5he1i Surrace Figure 1 - Shell Temperatums at the Top of the Dome (without PCS Film Flow)
The WGOTHIC code predicts the average energy transfer coefficient for the internal shell surface at the top of the dome to be about 67 BTU /hr-ft2 -F over the first 3 minutes. It continues to decrease after that as the shell temperature increases. The code calculated internal energy transfer 1 coefficient is only about 10% higher than the 60 BTU /hr-ft 2-F assumed in the hand calculations.
The bulk of the internal energy transfer for the dome surface is by condensation mass transfer i as shown in Figure 2. Therefom, the heat flux to the steel shell is limited by the condensation ;
rate.
4 i
Westinghouse Proprietary Class 3
. Preliminary
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CorwectIon + condensetIon Figum 2 - Comparison of Internal Condensation and Convective Energy Transfer at the Top of ne Dome The temperatures of both the wet and dry portions of the shell will continue to increase during the time required to establish steady state water coverage (10 minutes). Based on the shell temperature predictions shown above, the outer shell surface temperature for the dry regions of the dome and sidewall will not exceed 240*F before steady stae water coverage is established.
Tests run during the PCS testing program verified the ability of the water film to wet and rewet I a hot, dry surface (temperature exceeding 240'F) coated with the inorganic zinc compound to be used on the AP600 containment shell. Herefore, water coverage is not adversely affected by application of the film to a hot, dry shell surface.
In an attempt to quantify the amount of energy removal neglected during the development of i l steady state film coverage, the WGOTHIC base case described above was extended out to 1800 l
seconds to compare the shell temperature and heat removal results to a second case in which the l assumed water coverage delay time (for the top of the dome) was reduced to a more realistic j value. For the base case, the water film was applied at 660 seconds and for the second case, the water film was applied at 60 seconds. In both cases, the input water coverage fractions for the 3 portions of the dome (PCS bucket down to the first weir, between the first and second weirs, and from the second weir down to the springline) were set to 25%,70% and 90% to match the measured values from the phase 3 Water Distribution Tests.
5
Westinghouse Proprietary Class 3
. Prehmmary l f
Note, the WGOTHIC code assumes steady state water coverage develops instantaneously at the
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time the film is applied, i.e, the time required to fill the weirs and develop steady state coverage is bounded by the assumed 660 second time delay in application of the film. Although the second chse, with a more realistic estimate of the film application delay time for the top of the dome, will give a more accurate estimate of the heat removal from the top portion cf the dome, it will overestimate heat removal from the rest of the dome and sidewall since the code does not <
model the time required to fill the weirs and establish the steady state water coverage. Therefore, !
only the heat removal fmm the top of the dome will be compared to give a minimum value for the heat removal neglected.
I The transient inner and outer shell temperatures of the wet portion on the top of dome down to the first weir for both assumed PCS delay times are shown in Figure 3. The wet outer shell temperature increases to only about 165'F in the more accurate,60 second delay case. It is also interesdng to note that about 5 minutes after water is applied in the 660 second delay case, the wet shell temperatures decrease to about the same values as the 60 second water coverage delay case and that the difference in the coverage delay time doesn't seem to have much impact on the containment temperature.
The transient inner and outer shell temperatures for the wet and dry areas at the top of the dome for the 60 second delay case are shown in Figune 4. WGOTHIC models 1-D conduction (thmugh the shell) so conduction between the wet and dry areas is neglected. If azimuthal conduction were modeled, the temperature of the dry area would be lower and the temperature of the wet area would be higher. More water would be evaporated at the higher elevations so the amount predicted to reach the lower elevations (or runoff the shell) over time would be lower. Derefore, the use of a 1-D conduction model in the evaluation model results in a higher predicted runoff flow rate and reduces the amount of evaporative heat removal from the shell.
Figures 5 and 6 compare the transient and integrated energy removal rate from the top of the j dome as a function of time. Dere is very little difference in the energy removal rates for the l
first 300 seconds (due to the relatively long time constant of the shell), but the earlier application i
. of the water film does significantly increase heat removal after 300 seconds. He heat removal l rate for the 660 second delay case increases rapidly after the liquid film is applied and matches the heat removal rate of the 60 second delay case about 5 minutes later. Approximately 350,000 BTUs more energy is released from the top portion of the dome due to the earlier application of j water on the dome. The energy release from the lower portions of the dome and sidewalls (if j calculated with the proper weir fill delay times) would cause this difference to increase l significantly. Therefore, the assumed 10 minute water coverage delay time conservatively neglects the energy removal from containment during the initial water coverage transient.
6
Westinghouse Proprietary Class 3
. Preliminary 1
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Figure 3 - Comparison of Wet Shell Temperatums at Top of Dome (with PCS Film Applied at 60 and 660 Seconds) 7
Westinghouse Proprietary Class 3 Preliminary 8
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. Preliminary 8
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Westinghouse Proprietary Class 3 Preliminary Summary of the PCS Wetting Tests Observations and/or measurements of film coverage on the prototypical inorganic-zine coated surface were made in several PCS tests. This section provides a description of each test and a summary of results. Table 1 presents a summary of the ranges of the test parameters that characterize the film coverage for all the PCS wetting tests.
Water Film Formation Tests The Water Film Formation Tests (Ref. 3) were performed to show the wettability of the selected exterior coating for the AP600 containment shell and to characterize general requirements for forming a water film over a large surface area. An 8-ft, long,4-ft. wide steel plate was placed on a pivoting frame to simulate the various angles on the containment dome and sidewall. The ,
steel plate was painted with the selected inorganic zinc coating. A stream of water was applied I to the center top edge of the plate. Various film spreading mechanisms were investigated, but no source of heat was modeled.
1 With a flow rate of I gpm from a 1/2-inch diameter tube pointed vertical to the surface, the water I spread to form an initial 1-ft. wide stripe of film. The initial width appeared to be independent of the plate angle. The initial film thickness was not uniform near the point of application; it I was thinnest just below the application point and thicker on both sides. The film continued to i spread (more slowly as the surface became more vertical) and a very thin, wet region was created at the edges as the film traveled downward.
Water Distribution Tests The Water Distribution Tests were used to determine the water coverage fraction and estimate the time to establish steady state film coverage on the AP600. A full scale test section representing a 1/8 sector of the containment dome was built. There was no soume of heat to simulate energy removal by evaporation for these tests. Various weir distribution systems were tested before the design was frozen and tested in the phase 3 Water Distribution Tests (Ref. 4).
The water coverage fraction for the 27.5 gpm flow rate (equivalent to 220 gpm on the AP600) was estimated to be 25% from the top of the dome down to the first weir, and 70% between the first and second weirs, based on a review of the video tapes for the phase 3 water distribution tests (with the improved weir design). The entire vessel was wet at the bottom of the dome, but only the width of the visibly flowing water stripes were measured. A 90%, flowing water i coverage fraction was measured at the springline (below the second weir). The phase 3 test data l is summarized in Table 2.
11
Westinghouse Proprietary Class 3 Preliminary Table 1 - Test Film Coverage Parameter Ranges Large Scale Test Data Ranges Min. h ab6 Avg. Wet Surface Temperatum
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Applied Film Temperature F Runoff Film Temperature F Peak Dome Heat Flux BTU /hr-ft2 Peak Heat Flux at Bottom BTU /hr-ft2 Applied Film Flow rate Ibm /hr Top Sidewall Film Flow rate Ibm /hr-ft Bottom Sidewall Film Flow rate Ibm /hr-ft Exit Film Reynolds Number _ _
STC Wet Flat Plate Test Data Ranges
. -%jbo
- Wet Surface Temperature F Applied Film Temperature F Runoff Film Temperatum Average Heat Flux BTU /hr-ft2 Applied Film Flow rate Ibm /hr Top Plate Film Flow rate Ibm /hr-ft l
Exit Film Flow rate .
Ibm /hr-ft Exit Film Reynolds Number ,
Small Scale Test Data Ranges
. Avg. Wet Surface Temperatum F
bkO Applied Film Temperature F Runoff Film Temperature F Average Heat Flux BTU /hr-ft2 Applied Film Flow rate Ibm /hr Top Sidewall Film Flow rate Ibm /hr-ft Bottom Sidewall Film Flow rate Ibm /hr-ft Exit Film Reynolds Number , ,
Phase 3 Water Distribution Test Data Ranges g Applied Film Flow rate Ibm /hr i
Top Sidewall Film Flow rate Ibm /hr-ft Top Sidewall Reynolds Number -
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Westinghouse Proprietary Class 3
- Preliminary Table 2 - Summary of the Water Distribution Tests Water Distribution Tests (Cold)
Measured Tf-in Tf-out Exit Avg.
Test Coverage (F) (F) Flow-GPM lbm/hr Gamma Qflux
- - %bh !
13 9
10 11 12 14 1
l At the 220 gpm equivalent flow rate for the modeled 1/8 sector of the dome, there am [ ]" flow streams (with an average flow rate of about [ ]" gpm per stmam) from the fir:,t weir and [ ]"
streams (with an average flow rate of about [ ]" gpm per stream) from the second weir. ;
Closeups of the flow from the weir show how the water spreads radially outward from the point of application on the dome before merging with the streams on either side and flowing downward. The width of the stripes of water film increases as they fall between the first and ,
second weirs. .
l.
Assuming each stream from the first weir spreads out about 1-ft (based on the Water Film Formation Tests), the water coverage and film Re numberjust below the first weir (at the [ - ]"
radius) can be estimated for the scaled 220 gpm PCS flow rate as follows: i l
l Fractional Coverage = [ ]" = 0.92 F=[ ]" = 0.2 lbm/ft-s Re = 4*F/p = 4*0.2/.458E-03 = 1810 If the stripes of film did not spread at all (i.e. the thickness and width remained constant), the ]
coverage fraction just above the second weir (at the [ ]" radius) would be half this value, j 0.46. This is much less than the observed value of approximately 0.7 because the film stripes l were observed to spread significantly between the first and second weirs on the inclined (but not vertical) surface of the dome.
After passing through the second weir, the water coverage and film Re number are estimated similarly as follows (assuming the spread is only 0.5 ft per stream at the lower flow rate):
Fractional Coverage = [ ]" = 0.92 F = 0.1 lbm/ft-s Re = 4*F/p = 905 13
Westinghouse Proprietary Class 3 Preliminary if the stripes of film did not spread at all, the coverage at the springline (65-ft. radius) would be:
Fractional Coverage = [ ] = 0.70 This is less than the measured value of 0.9, so the film stripes also spread on the nearly vertical surface between the second weir and the vertical sidewall. The film Re number at the springline ,
f is estimated as follows: ,
P=[ ] = 0.0827 lbm/ft-s i
Re = 4*F/p = 722 -
Figure 7 presents the measured sidewall coverage as a function of the applied water flow rate for all of the Phase 3 Water Distribution Tests. The coverage decreases as the applied flow rate decreases. The flow rate was not. adjusted to account for the water lost at sampling points upstream of the springline. This correction would shift the data points slightly to the left. i
_ d,d
~
Figure 7 - Phase 3 Water Distribution Test Coverage as a Function of Sidewall Flow Rate 14
1 Westinghouse Proprietary Class 3
. Preliminary STC Wet Hat Plate Tests The primary purpose of the STC wet flat plate tests was to generate evaporation heat and mass transfer data with representative temperatums, heat flux, air velocity and film flow rates to bound the expected conditions on the AP600 containment shell. A secondary purpose was to observe the film hydrodynamics including possible formation of dry patches due to surface tension ;
instabilities.
Tests were performed in 2 orientations; vertical and 15 degrees from horizontal with various combinations of air velocity, film flow rate and heat flux. A wavy laminar water film was formed easily on the hot coated steel surface, even in the vertical orientation. Once formed, the film showed no instability or tendency to form rivulets. His was true at all tested water flow rates. A description of the test section and msults from the various tests are given in Ref. 5. The test data is summarized in Table 3. ,
Two of the heated flat plate tests wem run with vey low film flow rates at relatively high heat flux and the film did dryout before reaching the end of the test section. He observations are given in Ref. 5 (pages 36-37). "The upper part was 80% wetted and fingers of water film extended down four feet to within two feet of the end of the heated plate. The bottom of the fingers slowly moved up and down. The dry patch between fingers was between one quarter of an inch and one and one half inches wide. Rese tests showed that the end point of water films on the containment would still be stable film e vaporation, even with very thin films and high heat fluxes."
Small Scale Integral Tests l The small-scale integral tests wem designed to provide heat and mass transfer data for both the j inside and outside of the test vessel. He test apparatus consisted of a 3-ft. diameter,24-ft. high I steel pressure vessel that was heated by steam supplied at various pressures. The pressure vessel was surrounded by a clear, plexiglass shield that fonned a 15-in. wide annulus for either forced or natural circulation driven air flow and allowed observation of the applied extemal film flow.
The tests were conducted with vaging steam supply flow rates, water film flow rates, water film temperatures, inlet air flow rates, inlet air temperatum and humidity. Instrumentation was provided to measure intemal steam condensation rates, extemal water evaporation rates, inner and outer wall temperatures, film temperatures, air velocity, temperatures and humidity. A summary of the test data from Ref 6. (for tests with measumd water coverage) is provided in Table 4.
The following conclusions and observations (with aspect to the water film) were drawn from ;
these tests.
i
. The water film behavior was stable at average, evaporating heat fluxes in the range of those expected on the AP600.
15
Table 3 - Summary of STC Wet Flat Plate Tests STC Flat Plate Evaporation Tests Measured Measured Avg.
Test Coverage Tf-in Tf-out Mdot-in Mdot-out Inlet Exit Qflux Avg. Wet Plate Tem
(%) (F) .(F) (1bm/hr) (Ibm /hr) Ganna Gantna (B/hrft2) Max Min 13
~ - . . _ _ _ _ _ _ _ _ _ .
~ aj h) c 10 .
14 29 22 11 16 15 23 27 I o
17 g, 30 g 18 32
, g c
19 y$
R 25 20
~
- 26
{@G g.
21 3E3.p 12 Q 28 n
- ~
24 g
31
- ta STC Flat Plate Tests with film completely evaporated by exit
% Plate Tf-in Tf-out Mdot-in Mdot-out Inlet Avg. Wet Dry Avg. Wet Plate Tem Test Coverage (F) (F) (Ibm /hr) (lbm/hr) Ganna Qflux Plate Tem Max Min 8
a) b) c 9
O
- - - - -~ ,w ,,,w _ _ _ ,_
Table 4 - Summary of Small Scale Tests Small Scale Tests Approx. Measured Test Coverage Tf-in Tf-out Mdot-in Mdot-out Inlet Exit Avg. Avg. Wet Shell Tem
(%) (F) (F) (lbm/hr) (lbm/hr) Gamma Gamm,a Qflux Max Min 107A-15U _ p#
107A-5P 111-5P .
132B-15U Small Scale Tests with Film Completely Evaporated at Exit Approx.
(
g Coverage Tf-in Tf-out Mdot-in Mdot-cut Inlet Avg. Avg. Wet Shell Tem g-Test 9 4-ft El (F) (F) (lbm/hr) (Ibm /hr) Gamma Qflux Max Min se 105-15U
-------- ----- - _ g b c, ? ,
107C-15U '
J gy q 106-15U 132A-15U (7f m
109B-150 121-15U $ O' 114B-15U f
O iT w
O
, __ _. - __ _ _o-_ --_______m_~ __ _ __ _ _ _ _ _
,e_-_ _- _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _
Westinghouse Proprietary Class 3 Preliminary
- A uniform water film was easily formed on the coated steel surface using simple weirs.
. The water film on the vertical side walls of the coated steel surface of the vessel had no tendency to become less uniform o'r form rivulets, so that no water film redistribution was i required on the vertical walls.
Large-Scale Integral Tests The Westinghouse large-scale PCS test facility was built to provide test data fer a geometrically similar model of the AP600 containment vessel and PCS. He tests provide experimental data that can be used for evaluating the physics in containment, determining the relative importance of various parameters that affect heat and mass transfer and validating computer codes. Three series of tests were run at the Westinghouse large-scale test facility. He steady-state pressure, annulus air flow rate, water coverage, steam flow rate, injection velocity, location and orientation, and noncondensible gas concentration were varied between the tests.
The large-scale PCS test facility uses a 20-ft. tall,15 ft. diameter pressure vessel to simulate the AP600 containment vessel. He geometry is approximately a 1/8-scale of the AP600 containment vessel. A plexiglas cylinder is installed around the vessel to form the air cooling annulus. Air flows upward through the annulus via natural convection to cool the vessel, resulting in condensation of the steam inside the vessel. A fan is located at the top of the annulus shell to provide the capability to induce higher air velocities than can be achieved during purely natural convection. A liquid film is applied to the outside of the test vessel to provide evaporative cooling.
Test conditions (pressure, steam flow rate, cooling air flow rate, water coverage, etc.) were selected to provide heat and mass transfer validation over a range of conditions representative of a DBA. He Baseline and Phase 2 test data related to water coverage from Ref. 7 and Ref.
8 (excluding the tests with forced water coverage) is summarized in Table 5.
The liquid film was applied to the elliptical dome surface by J-tubes to produce a series of unifonnly spaced water streams. At water flow rates scaled to the initial PCS flow rate on the AP600, the water streams spread within a few inches of their application point to form a relatively thick, continuous wavy laminar film. At lower scaled PCS flow rates, the individual source streams were not able to spread to complete circumferential coverage. Evaporation and spreading on the inclined surface of the dome caused the thickness of the steams to decrease and the width (or coverage area) to increase as they flowed down the outer surface of the elliptical dome. De stream width was observed to remain relatively constant as it flowed down the vertical sidewall.
18 1
Table 5 - Summary of Large Scale Tests Largs Scale Tests Measured Test Cov. rage Tf-in Tf-out m-in m_out Exit Dome Max Exit Max Avg. Wet Shell Tem Baseline 1) (F) (F) (lbm/hr) (1bm/hr) Gamma Qflux Qflux Max Min
___.____ ________ ________ ________ ________ ________ ________ ________ ________ _________ qbc 201.1~
202.1 -
203.1 207.2 201.2 202.2 203.2 204.1 205.1 206.1 (
207.4 3 210.1 .
211.1 G ,o o
Test Phase 2 gh U 5f 202.3 EN 203.3 212.1A h k' 212.1B 212.1C O 213.1A h 213.1B w 213.1C 214.1A 214.1B 215.1A 215.1B 217.1A 217 .1B 218.1A 218.1B 219.1C 221.1A 221.1B --- _ _ . _ _ _ _ ~ -__-... _-._- _.
4 Westinghouse Proprietary Class 3
. Preliminary Expected Film Coverage Parameter Ranges for AP600 It is necessary to estimate the expected film coverage parameter ranges for AP600 to compare with the ranges of the PCS tests. The estimates for the maximum and minimum values of the film parameter range were determined using the simple approach described below.
The initial gravity driven PCS film flow rate (assuming a single failure of I of 2 valves to open) is 220 gpm. The transient PCS film flow rate for the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is shown in Figure 8. The minimum PCS flow rate is 55 gpm and occurs after about 3 days.
The minimum sidewall F value would be 0 lbm/hr-ft, assuming complete evaporation of the applied film. To detennine a maximum sidewall F, only 25% of the film is assumed to evaporate on the dome. It is likely that them would be mom evaporation from the dome, which would reduce the film flow rate to the sidewall, but this could also result in a lower sidewall coverage fraction. Assuming 25% evaporation of the applied PCS flow rate, the maximum sidewall flow rate would be 80000 lbm/hr. Based on measurements from the unheated, phase 3 Water Distribution Tests, a 75% coverage at the top of the sidewall is used.to obtain a maximum sidewall F of 256 lbm/hr-ft. At the predicted maximum 200*F film temperatum, the sidewall Ren , would be 1400. The Re n. and F values on the dome will be higher than the sidewall values since F decreases as the diameter increases. A more detailed comparison of the expected AP600 Re n value with test data is given in Ref. 9.
The shell heat flux decreases from the point of PCS film application, on the subcooled region of the shell, downward through the evaporating region of the shell and into the dry portion of the shell. The steady state shell average heat flux and film temperature were calculated for the subcooled, evaporating and dry portions of the shell assuming perfect mixing within containment and an ambient air and film temperature of 120*F. These calculations were performed at the containment design pressure,60 psia, to bound conditions at the expected DBA peak pressure and at 38.2 psi, for conditions representative of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after blowdown. The results are tabulated below.
Containment Avg. Subcooled Avg. Evaporating Avg. Dry Pmssure Heat Flux Temp. Heat Flux Temp. Heat Flux Temp.
(psia) 2 (BTU /hr-ft ) (.F) (BTU /hr ft ) (*F) (BTU /hr-ft 2
) (.p) 60 7740 155 5500 190 455 260 38.2 3700 147 2500 175 300 220 The maximum wet shell heat flux is conservatively estimated to be 50% higher than the average 2
subcooled value (at 60 psia), about 11500 BTU /hr-ft. The minimum wet shell heat flux is conservatively estimated to be 50% lower than the average evaporating value (at 38.2 psia), about 1300 BTU /hr-ft2 . Note, the minimum wet shell heat flux could be even lower if the pmssure at 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is lower than assumed, however, the minimum wet shell heat flux is not a bounding value anyway.
20 i
Westinghouse Proprietary Class 3
. Preliminary
- 4) C 1
l 1
l Figure 8 - Gravity Driven PCS Flow Rate as a Function of Time i
21
Westinghouse Proprietary Class 3
, Preliminary Per the Technical Specifications, the initial PCS film temperature is expected to be between 50 and 120*F. He 120*F value is used in the DBA evaluation model to minimize the benefit of sensible heat removal by the subcooled film. The film temperature will increase as the film i flows down the dome and onto the sidewall. The maximum evaporating film temperature was calculated to be less than 200*F. Since the resistance to heat transfer in the thin film is very small (compared with the mass transfer and internal resistance, as shown in Ref.12) and the heat flux is relatively low, the maximum wet surface temperature is expected to be less than 20*F higher than the maximum film temperature.
The expected range of the AP600 film parameters is summarized in Table 6. A comparison with !
the PCS test data ranges shows that, with the exception of the maximum evaporating film temperature and maximum sidewall Re n, number, the test data bounds the expected range of the AP600 film parameters.
It is more important to bound the lower expected film temperature with the test data, than the higher expected film temperature since the film is less stable at lower film temperatures. Also, it is more important for the tests to bound the minimum sidewall Re.m c for evaluating the film stability model. Herefore, even though the test data does not bound the expected maximum film temperature or maximum Ren ., the ranges are sufficient for evaluating the Zuber-Staub film ;
stability model. Also note, the test data for the maximum sidewall Ren . number is within the .
wavy laminar flow regime, while the maximum AP600 sidewall value is in the transition to l turbulent flow regime. Heat transfer within the turbulent flow regime is better than in the laminar flow regime, so even though the tests did not cover the transition regime, the test results are cons;rvative with respect to evaluating the heat transfer.
Table 6 - Expected Range of AP600 Film Coverage Parameters AP600 Composite of Test Data Min Mas. ~
Min Mia AA Wet Surface Temperature 220' F ~F Wet Surface Heat Flux 1300 11500 BTU /hr-ft2 BTU /hr-ft2 Applied Film Flow rate 55 220 gpm Sidewall Film Flow rate 0 256 lbm/hr-ft Ibm /hr-ft Applied Film Temperature 50 120' F F Evap. Film Temperature 200* F F Sidewall Film Reynolds Number 0 1400 . .
22
Westinghouse Proprietary Class 3
. Preliminary Determination of a Bounding Stability Margin (R,,,) Value To provide a conservative estimate of the initial sidewall water coverage for AP600, it is necessary to determine an upper boundin'g value for the minimum stable film flow rate on the dome. In the Westinghouse film coverage model, the local Zuber-Staub minimum stable film flow rate on the dome, F., is multiplied by a stability margin value, R,,,, to detennine an upper bound, below which a continuous film on the dome will split (Ref. I1). He stability margin multiplier is used to account for the effects of subcobling, plate misalignment and the method of film application on the initial film splitting behavior.
The stability margin value that is used in the Westinghouse film coverage model to determine the initial film coverage on the sidewall was obtained by bounding the film coverage test data from the unheated, full-scale Water Distribution Tests and the heated 1/8-scale Large Scale Tests covering a wide range of film flow rates and heat flux. The method used to determine a bounding N, value of the test data is outlined below.
- 1. The Zuber-Staub stability model is used with: a wetting angle of [ ]", the measured peak dome heat flux, the initial film flow rate at the point of application, and the initial film temperature to determine' a maximum value for F.. This F. value is multiplied by N, to determine the dome cin:umference, CI, at which the average film flow rate becomes unstable.
- 2. The wetted coverage (width of the film stripes) at the circumference of the vessel .
springline, CSL, needs to be estimated for comparison with the measured test data and l was predicted using the following approximation-WDL = (CI + CSL)/2 j
- 3. Based on observations from the Large Scale Tests, the width of the film stripe mmains relatively constant from the springline down to the point of measurement (at the vessel gutter). Herefom, the predicted film coverage at the springline is compared with the ;
measured film coverage and the R,,, value is varied until all of the data is bounded.
]
This approach yielded a bounding R,,, value of [ ]" at the assumed [ !" wetting angle. The results are shown in Figure 9. De ratio of the predicted-to-measured film coverage is shown ;
as a function of the maximum heat flux in Figure 10. His shows that this method for determining the coverage bounds the measured test coverage values over a larger range of heat flux than is expected on the AP600 shell.
i l
I l
e 23
Westinghouse Proprietary Class 3
. Preliminary 0
I nu m m m -
g l m !
1 m
m A mW m m 5 m
mu - g i
.* , m m k a m u l H
89 g c e o m 8,m ,
O u a m e b m .
g g-8 -
8 R
i i i i i ;, .
2 r
8 e
E S S R 7 C%) eSeJeAog peloipe;d .
Figure 9 - Bounded Water Cov rage Data 9
24
Westinghouse Proprietary Class 3
- Preliminary N
M M
~
M g g M
M u.
M
- p T
%" =* Is
, o M
w *"
M g*
- gu o Is 2-O 6- U-
. tr}
I 4J E M d b
i X
W .
n MM M
I l I I I I h
e " 9 9 9 9 e t e e t e Q Q o o o O O O O 11x3 gu uoigonJd e6nse^og peunsuon/pegogpeJd Figure 10 - Bounded Test Coverage Data as a Function of Heat Flux 25
I i
Westinghouse Proprietary Class 3 i Preliminary Sensitivity to the Assumed Wetting Angle The sensitivity of the predicted Zuber-Staub r value to the wetting angle is shown as a function of heat flux in Figures 11 and 12'(for film temperatures of 120 and 200*F mspectively).
Using a higher wetting angle or lower film temperature would cause the Zuber-Staub P., value to increase, which would cause the bounding R,,, value to be lower (since the test data is bounded by the product of F., and R,,,). Therefom, the method for determining the bounding coverage at the vessel springline is conservative at any assumed wetting angle.
The surface wetting angle (advancing film) was measured as a function of temperature and age of the surface. These results am pmsented in Ref.10 and show the advancing film wetting angle for this surface is between [ ]. A value of [ ]'* was chosen for the film stability calculations because it is the upper bound of the measured, steady state values for a heated, weathemd surface. Other test data, presented in Figure 11 and shown in Tables 3,4 and 5, indicate that the surface wetting angle, which should be used in the Zuber-Staub stability model, should be smaller. ;
l 1
l 1
l 26
Westinghouse Proprietary Class 3
- Preliminary i 1
o l
i I
1 a
8 <j
$9
~
C 1
++ h 3 I g
i U !
E i i '
U l a
l o u + I- l}
e o +
+ 2 u.
dl O II ll m
5 I
' 1 t g i
' r g g o o 8
n e e m .i e
\\ n C14-J4 /WAl ) tuww)
{
Figure 11 - Minimum Stable Film Flow Rates Pedicted by the Zuber-Staub Model Showing Sensitivity to Heat Flux and Wetting Angle at 120*F Film Temperature l
27
Westinghouse Proprietary Class 3 Preliminary l
e I
i a
<l e
I
+ h 3 I
<i , ,
g i s :
i s
3 5 1
<i o n+ r Hg a E U +
u.
'I (f If fl a
- I I
- g
! ! ! 5 !f
,, a Cu-su /wqi ) auwoo Figure 12 - Minimum Stable Film Flow Rates Predicted by the Zuber-Staub Model Showing Sensitivity to Heat Flux and Wetting Angle at 200*F Film Temperature 28
. - - - . - . - - - . . . . - . - . - - - _ .- .. . . . - - _ . _ . _ _ - =-
4 .
Westinghouse Proprietary Class 3
, . Preliminary Sample PCS Film Flowrate Calculation The gravity driven PCS film flowrate is conservatively calculated assuming one of two PCS drain valves fails to open. The gravity driven flowrate is based on the PCS water storage tank level and is shown as a function of time in Figum 8. A suitable, maximum value for P that bounds heat fluxes up to 10000 BTU /hr-ft2 -F and film temperatures greater than 120 F (the initial film i temperature) for a wetting angle of [ ]" was selected from Figure 13.
3 The wetted perimeter at the springline is calculated by first detemiining the point on the dome where R,,,P ,is reached and the film is predicted to split r# 2nR g
=
t i
The wetted perimeter at the springline is given by the minimum of the vessel cimumference, t 2 n r,,,,,, and .
P = n(r,+ ry The film evaporates as it flows down the venical sidewall, causing P to decmase. The average heat flux, Q,,", is assumed to remain constant over the entire wetted sudace. A conservatively low value for Q,," is used to minimize the evaporation rate and maximize the amount of film that is calculated to run off the surface. 'Ihe distance down the venical sidewall at which the film reaches P, is calculated as the minimum of ,
(% - r.'J h, .
Z* = P l 4"s=amdm ,
and the sidewall height. From this point on, the wetted perimeter (or film coverage) is conservatively assumed to decrease as the film continues to evaporate at the constant stability limit, P,.. This assumption is conservative because, in the PCS tests, the film stripes were observe 4 to continue to thin while maintaining a relatively constant width until they were completely evaporated.
29 .
e Wesdnghouse Proprietary Class 3
. Preliminary The rate of change of the film flowrate with height is related to the evaporadon rate dP " Q""
r* dz - r" hh Solving for P(z) gives the exponendal function r(z) = r e
-4" The film mnoff flowrate at the bottom, Z,. , is
=
- r,r , -d",g,,- z,y,g He PCS flow that will be applied in the evaluation model is the difference of the gravity driven PCS flowrate and the runoff flowrate. The calculations are summarized in Table 7.
l 1
30
': : - t ;: y ;
$aEDoh ga:2 n h O a <a a t
. T2ysoQ 0
s 0
0
. 0 0 -
1 0
0 i
0 )
0 1 2' t
f
- F r
h
/
0 2
U 1 -
T
. - B ;
(
x u
l F
F 0
t 0 0
a 2
= 0 e 0
1 H :
I m
I F
- ' - 0 0
1 0 0 0 o a 0 5 0 s
2 1 O%iL# hS U f@
1&
1 ! . 2 . 3 3=in oE C . E..B5cB v>E tea 2 3 ]oE g Br, ga,nsc o 9a NcX.,0[# o / C
.. : r 1 N' ,rac<{ 0lIaN2cMgo2B aByagg E , - - I,g,5 Ngo
Table 7 - Input PCS Flowrate for the DBA Evaluation Model Rref =
Zmax =
[
83.458
]
hfg = 1000 Time PCS Flow Gammin Wsprng Avg. Q Zmin Wexit Runoff PCS Net (s ) (1bm/s) (1bm/hr-ft) (ft) (BTU /hr-ft2) (ft) (ft) (1bm/s) (1bm/s) g,> g, o > 120 327.4468 7000 30.60318 15.00116 0.500039 600 120 327.217 4500 47.51855 85.02066 2.834022 1200 120 326.9873 4500 47.43203 84.68576 2.822859 1800 120 326.7576 4400 48.42142 90.4271 3.014237 2400 120 326.5278 4200 50.63424 103.5116 3.450387 3000- 120 326.2981 3800 55.86127 136.1715 4.53905 16 3600 120 326.0684 3400 62.31803 179.1353 5.971176 3 7200 120 324.69 2300 83.458 324.69 10.823 @-
18000 120 320.4738 1500 83.458 320.4738 10.68246 TF 19800 120 267.7711 1400 64.86209 215.5473 7.184909 0 32400 120 266.3116 1300 66.99671 222.8138 7.427127 }fh 54000 120 263.8792 1200 67.3493 224.6187 7.487291 75600 120 261.2846 1200 61.6628 210.1157 7.003856 3
=r.o, 3
77400 120 253.3387 1200 43.5233 169.9289 5.664297 5' 93600 -
120 251.8792 1200 40.06714 163.2105 5.440351 d! ]*],
u, . -. -
N O
m
_________s,w _ - - __- r, - -
. ., ys w -,- - -_ _
, a Westinghouse Proprietary Class 3 o Preliminary References
- 1. Frank Kreith, " Principles of Heat Transfer",3rd Edition,1973
- 2. W. A. Stewan, " Natural Convection Cooling of AP-600 Containment", Westinghouse R&D Report 87-8J0-PASIV-RI, April 1987
- 3. A. T. Pieczynski, W. A. Stewan, WCAP-13884, " Water Film Formation on AP600 Reactor Containment Surface", February 1988
- 4. J. E. Gilmore, WCAP-13960, "PCS Water Distribution Phase 3 Test Data Repon",
December 1993
- 5. W. A. Stewan, A. T. Pieczynski, L. E. Conway, WCAP-12665 Rev 1, " Tests of Heat Transfer and Water Film Evaporation on a Heated Plate Simulating Cooling of the AP600 Reactor Containment", April 1992 6 R. E. Batiste, WCAP-14134, "AP600 Passive Containment Cooling System Integral Small-scale Tests Final Repon", August 1994 7 F. E. Peters, WCAP-13566, "AP6001/8th Large Scale Passive Containment Cooling System Heat Transfer Test Baseline Data Repon", October 1992
- 8. F. E. Peters, WCAP-14135, " Final Data Repon for PCS Large-Scale Tests, Phase 2 and .
Phase 3", July 1994 ;
l
- 9. D. R. Spencer, Enclosure 2 to Westinghouse I.etter NTD-NRC-94-4100, " Liquid Film Model Validation", January 1994
- 10. R. Wright, PCS-GSR-003, "A Method for Determining Film Flow Coverage for the i AP600 Passive Containment Cooling System", July 1994 l l
- 11. R. Ofstun, i.etter NTD-NRC-%-4635, " Summary of Applicability of the Zuber-Staub Film stability Model and Method to Address Water Coverage in the AP600 PCS Evaluation Model", January 1996
- 12. D. R. Spencer, WCAP-14190, " Scaling Analysis for AP600 Passive Containment Cooling System", October 1994 33
_ _ - _ _ _ _ _ _