ML20035E063

Summary of 920623-24 Meeting of ACRS Thermal Hydraulic Phenomena Subcommittee in Bethesda,Md to Continue Review of Westinghouse & NRC Proposed Test Programs in Support of AP600 Passive Plant Design Ceritification

ML20035E063
Person / Time
Site:	05200003
Issue date:	08/07/1992
From:	Catton I Advisory Committee on Reactor Safeguards
To:	Advisory Committee on Reactor Safeguards
References
ACRS-2830, NUDOCS 9304140230
Download: ML20035E063 (62)

Text

{{#Wiki_filter:- h-dg@ ' CERTIFIED BY: I. Catton - 8/7/92 DATE ISSUED: 7/27/92 F2% ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 9/f/(3 THERMAL HYDRAULIC PHENOMENA SUBCOMMITTEE MEETING TEST PROGRAMS IN SUPPORT OF H AP600 DESIGN CERTIFICATION JUNE 23-24, 1992 BETHESDA, MARYLAND EURPOSE: The purpose of the meeting was to continue the Subcommittee's review of the Westinghouse Electric Corporation's and the NRC staff's proposed test programs in support of the AP600 passive plant design certification. ATTENDEES: ACRS Westinchouse I. Catton, Chairman B. McIntyre T. Kress, Member L. Hochreiter D. Ward, Member E. Piplica "V.J." Dhir, Consultant L. Conway V. Schrock, Consultant N. Zuber, Invited Expert HEC E. Beckjord, RES B. Sheron, RES L. Shotkin, RES R. Jones, NRR i A. Levin, NRR MEETING HIGHLIGHTS, AGREEMENTS, AND REOUESTS June 23, 1992 Subcommittee Chairman's Comments Dr. Catton noted that the first day's presentations will be devoted to discussion of the Westinghouse (H) test and analysis programs that support the certification review for the AP600 design. The chairman noted that.. the Committee has been tasked by the NRC l Chairman to investigate the following issues: ~ Is the H-sponsored low-pressure facility located at Oregon e State University (OSU) adequate vis-a-vis the Agency's data needs? If it is not, what can be done? I e Will the high-pressure SPES facility provide adequate data? e What are the atypicalities associated with the ROSA facility? i In sum, the Subcommittee needs to determine if the combination of test programs planned by H (separate effects, OSU tests, and SPES) g ' \\ 9304140230 920807 E '* C b PDR ACRS 2830 PDR

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I r r 1 l 4 l T/H Phenomena Sub. Mtg. 2 June 23-24, 1992 ] will provide the necessary data to confirm that the AP600 design will perform as intended. j Dr. Catton said that H has not provided the Subcommittee with the l necessary documentation to address the above tasks. Westinchouse Presentation (Open Session) B. McIntyre noted the purpose of the day's presentations and j presented an overview of the H approach to its test and analysis program. In brief, H will perform a mixture of: scaled-to-full-scale design verification and component

tests, low-pressure l

l integral tests (OSU), and small-and larger-scale system tests (containment cooling tests) in order to obtain the needed data for l code validation in support of design certification. In addition to the above, H has entered into a cooperative integral system test program with the NRC. This program will include H-sponsored full-i height, full-pressure (FHFP) testing in the Italian SPES facility, and NRC-sponsored FHFP testing in the Japanese ROSA facility. In response to Dr. Catton's concern that no supporting written data j has been provided to the Subcommittee regarding the OSU and SPES ~ facilities (scaling analyses etc.), Mr. McIntyre indicated that j this work is still on-going. McIntyre did note that H has completed its SSAR analyses and some of this information will bu presented to the Subcommittee today. An overview of the H test program that addresses the AP600 passive j safety system features was provided by Mr. E. Piplica. These test programs consist of both separate ef fects and integral system tests. Piplica said that H has established an aggressive test l program and intends to have completed all testing by the end of CY 1993. Figure 1 summarizes all the passive safety system tests, l their status and schedule. Figures 2-8 give details of the individual test programs. Dr. Catton again expressed concern with M's lack of scaling documentation. Mr. McIntyre noted that a rough draf t report of the OSU scaling analysis exists and can be made available to the i Subcommittee, given the ACRS' upcoming review of this matter. i [ Note: a copy of this report was provided to the Subcommittee.]. i In. response to Subcommittee questions, H indicated that the OSU facility will be available for use by the NRC staff following completion of the H test program. 1 W Presentation (Closed Sessioni 'l j

~.. i l 5 + } T/H Phenomena Sub. Mtg. 3 j June 23-24, 1992 I I i ) l PAGES 3-6 l CLOSED SESSION DELETED DUE TO PROPRIETARY INFORMATION FOIA EX (b) (4) ~. i ) I t l } I ? t i l J .I l l I 1 .) J l 'P i 'i

f .l a t T/3 Phenomena Sub. Mtg. 7 June 23-24, 1992 i r i CLOSED SESSION DELETED DUE TO PROPRIETARY INFORMATION FOIA EX (b) (4) j l i l i i . I June 24. 1992 (Ocen Session) Reports of ACRS Consultants on NRC/INEL Meeting to Discuss Use of ROSA-IV to Simulate AP600 l I i

~ l T/H Phenomena Sub. Mtg. , 8 June 23-24, 1992 Dr. Catton requested that the three Subcommittee Consultants present provide a brief report summarizing their impressions of the June 3-4, 1992 meeting they all attended which was held at INEL at Idaho Falls, Idaho. The purpose of this meeting was to discuss matters associated with the use of ROSA-IV to simulate AP600. Key i to these discussions was an analysis performed by INEL (NUREG/CR-5853), using RELAP5/ MOD 2.5, which evaluated both the fidelity of ROSA vis-a-vis the AP600 configuration, and the impact of varicus facility modifications deemed necessary. Dr. Zuber e The INEL investigation of ROSA's applicability as documented in NUREG/CR-5853 was of a high technical caliber;

further, INEL verified, on a technical basis the concerns that NRR initially expressed regarding the need for FHFP ISTs.

INEL shows that the results of a given transient in AP600 are very sensitive to initial conditions. This result mandates a detailed characterization of the initial conditions used in any low-pressure integral tests. j l Concerning use of the ROSA facility, INEL calculations show i e that the effect of facility distortions may render test results that are scenario-dependent.

Also, RELAPS is incapable of simulating asymmetric T/H effects.

Thus the configurational similarity of ROSA with that of the AP600 must be maintained.

• Believes that the AP600 design will be found to be " safe".

i The configurational and geometric distortions seen in e ROSA-IV must be closely studied if this program is undertaken. Mr. Schrock e Agreed that INEL did a good job on this study. The MOD 2.5 version of RELAPS was used; MOD 3 will soon be applied to this study, as the code is now considered functional. ) i' to diverge with time (as compared to the AP600 plant e Results of ROSA simulations are scenario dependent and tend response).

• There will be a small (0.4 meter) loop seal in ROSA which is aprototypic of AP600; E urged that it be removed.

They are to supply justification for this action as RES does not believe its removal is cost effective. l l

T/H Phenomena Sub. Mtg. 9 June 23-24, 1992 Believe a rigorous evaluation of the proposed ROSA instrumentation will result in cost savings. suggested that the INEL study be more closely scrutinized e given the rapid pace of the ROSA program. Dr. Dhir Is concerned with the potential atypicalities seen in both SPES and ROSA. Also, he hasn't seen a plan for the necessary enhancement of the RELAP5 code models for simulation of AP600.

• Three levels of facility modifications were proposed for ROSA.

Combined with the needed modifications for SPES, a total of - $15M may have to be spent. Believe its more cost-effective to use a single facility. As such, he favors use of ROSA over SPES. NRR Presentation - Views on Confirmatory Testinct Mr. Jones discussed the objectives of confirmatory testing in general and the use of ROSA for such testing in particular. Confirmatory programs give the staff independent testing capability and allows for follow-on investigation as necessary. Concerning use of-ROSA, NRR-supports this program for a number - of reasons including: ability to conduct tests at a scale larger than SPES (by a factor of - ten); the facility will be under more direct NRC control; and, the distortions that will exist should be able to be addressed by use of analysis. NRC-RES Presentation - Introduction Dr. B. Sheron noted the _ following points in response to the comments of the Consultants noted above:. e NRC has spent - one year's time and $0.5M in analysis on the ROSA project; the staff is not rushing into this endeavor.

• Regarding the facility distortions seen in ROSA,.the purpose of the program is to investigate the functioning of the AP600's passive safety features and - to capture the. key -

phenomena associated with same; it is not a demonstration facility. JAERI is paying for all costs associated.with use of ROSA e including test conduct, data preparation and data reports. e-INEL's analysis shows that there is not a significant effect on test results due to the loop seal. Dr. Hochreite'r indicated that H's reanalysis of the impact of the loop seal confirms RES's position here.

T/H Phenomena Sub. Mtg. , 10 June 23-24, 1992 RES is not in a position to judge the acceptability of the e t SPES facility. We are still awaiting the necessary information from W. l As a result of further discussion, Dr. Zuber said that NRR should be asked to justify why the use two high-pressure facilities versus one low-pressure facility is acceptable, instead of the reverse. Dr. Catton requested that NRR address this matter later in the day. 1 Dr. Sheron also noted that RES has initiated a comprehensive scaling analysis program for ROSA. RES also performed a "PIRT" (process inherent ranking table) in conjunction with the ROSA facility analysis. Dr. Catton requested a copy of the report on j the ROSA scaling analysis effort. [ Note: this report has been formally transmitted to the ACRS Office.] RES has, with the conclusion of the June 3-4, 1992 INEL meeting, reached agreement on the facility modifications, instrumentation, [ and test matrix for ROSA. Commission approval of the RES program for ROSA testing is requested by June 30, 1992. Dr. Catton said that if Commission approval to proceed with use of ROSA is. sought by June 30, the ACRS will be "out of the loop" via any Committee comment during its July, 1992 Meeting. Dr. Beckjord said the June 30 date is critical, due to schedular pressures i associated with

ROSA, including the.need to begin timely negotiations with the Japanese-contractor responsible for fabricating the necessary facility modifications.

l ROSA Proctram Status Dr. Shotkin briefly reviewed the history of the RES's involvement with the AP600 test programs, including that proposed at ROSA.- Figure 28 list the status of activities associated with the ROSA /AP600 test programs. Dr. Shotkin indicated that RES will i sponsor both pre-and post-test predictions of the ROSA tests. l Figure 28.. provides a detailed schedule associated with implementation of the AP600 test program. Status and Development Plans for RELAP5 The status and development plans for RELAPS were noted by N. Laub'en j (RES). Correction of past errors and enhancement of the code's-capabilities is proceeding in three Phases. For Phase I, the code l was modified to model advanced LWRs (AP600 and SBWR) and a root cause analysis was undertaken to address serious problems with Version 8 of MOD 3. Figure 29 summarizes the problems found and the recolutions utilized. The Phase I effort was complete on May'1, j 1992. In response to questions from Drs. Catton and Dhir, Mr. Lauben said that problems seen with the downcommer model will be i r 9 x-6 7

~ I I T/H Phenomena Sub. Mtg. . 11 June 23-24, 1992 addressed later; some of the Phase I fixes will be further improved in later Phases of this effort. During further discussion, Dr. Hochreiter expressed concern with l the possible general release of an AP600 version of RELAP5; as this code's validation is based on use of (proprietary) test data, such information could lead to compromise of H proprietary information. Dr. Beckjord acknowledged this point and indicated he would pursue this matter. A set of Phase II modifications is currently underway (Figure 30). These modifications are planned to be complete by the end of this year. In addition, a set of " Phase III" code modifications is j under consideration (Figure 31), following the completion of the Phase II work. NRR Position on Need for Two Hich-Pressure Test Facilities i Mr. Jones provided comment in response to Dr. Catton's request for l NRR's justification of the need for two high pressure test facilities and one low-pressure test facility, instead of the ) reverse which was originally planned to be the case. Mr. Jones noted that at the time NRR authored its SECY on the need for H to l perform FHFP IST in support of AP600 design certification, NRR and l RES made a joint decision that the OSU facility, given the modifications H made at NRC's behest, was quite similar in capability to any facility NRC would have proposed. Given this, and H's decision to allow NRC access to OSU, the staff decided to use OSU instead of constructing its own low-pressure test rig. As a result of further discussion, Mr. Jones indicated that use of a single low-pressure facility is acceptable; while important j l concerns exist a low pressure, the key issue is just what phenomena l are seen while getting to low pressure (via blowdown of the ADS I l valves). As such, the high pressure IST facilities and the ADS SE tests performed by H are important in this regard. RELAPS Code Development Mr. N. Lauben discussed the status of the RES effort to apply the CSAU (code scaling, upplicability, and uncertainty) approach to development of RELAP5 for the modeling of the advanced LWRs (AP600 and SBWR). Mr. Lauben noted the following points: I e The following assumptions apply to the use of CSAU: the code l-is frozen and its associated documentation is complete; the l assessment matrix is complete, sufficient information is available and expertise exists to perform a valid PIRT. e Since the above assumptions do not apply to use of CSAU for code development, an iterative process is necessary to 1

l ~ l l T/H Phenomena Sub. Mtg. , 12 June 23-24, 1992 continually review: code applicability, scenarios, code input and experimental needs. When these iterations are complete, the process reverts to a " normal" CSAU. i l Some exceptions are noted for this iterative process. The e process does not distinguish between developmental and " independent" assessment, except to the degree the code is " frozen". Also, during the selection and re-evaluation of the scenario analyzed, the viability of a " combined" scenario approach is evaluated. At this time, RES is involved in the second of at least three iterations. Evaluation of the code uncertainties cannot be performed until th' completion of the assessment process, which, in turn, depends on an adequate experimental data base. In response to Dr. Catton, Mr. Lauben said that the MOD 3 version of RELAPS cannot be used for evaluation of AP600 because it is not sufficiently mature, and its associated documentation is not complete. Dr. Catton indicated that to successfully model AP600 plant phenomena, MOD 3 needs to be able to: adequately model stratified flow in horizontal pipes, contain a multi-dimensional downcommer model, and model split flows at "T"-junctions and the CMT inlet. As a result of further discussion, Dr. Catton requested that RES meet with the Subcommittee when RES has completed incorporation of the model changes / enhancements to MOD 3 that result from this developmental assessment effort. [ Note: a Subcommittee meeting during September, 1992 appears timely.] Dr. Dhir asked if RES has a plan for obtaining the needed experimental data to support model development / revision. Mr. Lauben said that they do not, at this time; the need for such data vill pend completion of the evaluation of the H experimental program to see if this data will suffice. In response to Mr. Schrock, RES.said that they do not have a completion date for the CSAU analysis effort. INEL Study - Evaluation of ROSA Fidelity to AP600 Desian l Results of the INEL evaluation of the ability of the ROSA facility to simulate AP600 were presented by Dr. M. Ortiz. Dr. Ortiz noted the key components of the LWR passive plant research program (Figure 31). The end point for this effort is validation and assessment of the RELAPS code. l At Dr. Catton's behest, Dr. Ortiz briefly reviewed the results of the INEL evaluation of ROSA's ability to simulate the AP600 design. Three levels, or sets, of modifications were evaluated vis-a-vis their resultant impact on the fidelity of ROSA to that of AP600 l l

T/H Phenomena Sub. Mtg. , 13 June 23-24, 1992 (Figure 32). A schematic of the final set of modifications chosen by RES is given in Figure 33, and is discussed below. Mr. J. Cozzuol briefly reviewed the results of some of the. AP600/ ROSA comparison calculations performed by INEL. These calculations reinforced the points made earlier by Dr. Zuber, et. al. regarding the need to ensure close geometrical and configurations similitude of any experimental rig with that of the AP600 prototype. Mr. Cozzuol also noted the INEL is performing calculations to assess the impact of the final set of ROSA modifications. Final Modifications to ROSA Dr. B. Sheron detailed the proposed final set of facility modifications proposed for ROSA. He noted that these modifications were finalized following the June 3-4, 1992 meeting held at INEL l that was discussed earlier today. Figures 34-35 list these l modifications. The instrumentation for ROSA was briefly reviewed by Dr. Ortiz. Figures 36-37 detail this instrumentation. D. Bessette discussed the test matrix propose for ROSA. Transients of interest include: SB LOCA, pressure balance line breaks, steam line breaks, and SGTR. It is envisioned that 10-12 tests will be run in the first year of the program, with a second year's time available for optional testing. Figure 38 gives the preliminary test matrix. In response to Dr. Catton, Dr. Hochreiter indicated that H plans to perform its own calculations of ROSA tests.

Further, H is interested in SPES/ ROSA counterpart tests.

Mr. Schrock urged RES to evaluate the impact of the specific location of a tube rupture (hot-leg vs cold-leg side) for the SGTR tests. Closina commente Dr. Hochreiter thanked the Subcommittee for its time over the past two days. He noted concern with the fact that the Subcommittee seems to be expecting some kind of " demonstration tests," instead of testing to ensure the capture of all key T/H phenomena associated with the AP600 design. Dr. Catton indicated, in reply, that H needs to address five key areas in its test program: Phenomena occurring in the downcommer' e e Horizontal stratified flow Flow seen at "T"-junctions e Phenomena associated with the CMT e Loop-to-loop flow oscillations e

~ T/H Phenomena Sub. Mtg. _ 14 June 23-24, 1992 Dr. Hochreiter indicated that he believes that W has, and/or will, satisfactorily address all these areas over the life of its test program. Dr. Shotkin made the following points: e ROSA will give useful data f rom high-to low-pressures, thus overlapping both the SPES and OSU tests.

• Modifications to the RELAP/CONTAIN code will be incorporated in time for assessments against data in CY-93 (W-sponsored tests) and CY-94 (ROSA tests).

e The key aprototypicality of RCSA is the lack of two cold legs per loop. Thus, loop-to-loop flow oscillations cannot be simulated. The SPES facility can supply data relative to this issue, however. RES is also investigating the addition of piping connections to overcome this limitation (Figure 39). e Other facility limitations are minor and can be addressed via analysis. Executive Session The Subcommittee agreed to bring this matter to the ACRS for its review. Prior to adjournment, Dr. Catton instructed representatives of W, NRR and RES concerning the content of their presentations to the Committee on this matter during the July ACRS Meeting. The meeting was adjourned at 4:20 pm on June 24, 1992. FUTURE SUBCOMMITTEE ACTIONS ON THIS MATTER AND ITEMS FOR FOLLOW-UP Future Subcc$tmittee Actions Tise Subcommittee will continue its review of this matter pursuant to the progress of the NRC/W test programs. The next Subcommittee meeting appears timely in the September / October timeframe to review the status of the CSAU effort as applied to the RELAPS/ MOD 3 code. Follow-un Items

1. Dr. Catton requested a copy of the W report that addresses the temperature bias seen from the LOFT external thermocouples (so-called " fin effect").

T/H Phenomena Sub. Mtg. , 15 June 23-24, 1992 i 2. Dr. Catton requested a copy of the report on the ROSA scaling I analysis effort. [ Note: this report has been formally transmitted to the ACRS Office.]

3. As a result of further discussion, Dr. Catton requested that RES meet with the Subcommittee when RES has cc pleted incorporation of the model changes / enhancements to MOD 3

. hat result from this i developmental assessment effort. [ Note: a Subcommittee meeting during September, 1992 appears timely.1 j BACKGROUND MATERIAL PROVIDED TO THE SUBCOMMITTEE FOR THIS MEET.ING

1. ACRS Letters, dated March 10, and April 6, 1992 dealing with the issue of FHFP integral system testing in support of the AP600-design certification effort.

I i 2.

Memo, P.

Boehnert to ACRS, dated April 29, 1992, transmitting April 22, 1992 Commission SRM addressing confirmatory integral system testing for the W AP600 passive plant design.

3. Memo, dated May 27, 1992 "For the Record" from A. Bates, SECY, i

detailing May 5, 1992 meeting between I. Catton and Commissioners Selin and Remick.

4. Memo, dated May 15, 1992 to J. Hoyle, SECY f rom E. Beckjord, RES referring to May 5, 1992 I.

Catton/ Commissioners meeting.

5. INEL Report, NUREG/CR-5853: " Investigation of the Applicability and Limitations of the ROSA-IV Large Scale Test Facil-ity for AP600 Safety Assessment" (Draft), dated May, 1992 i

6. Westinghouse Topical Reports dealing with various aspects of the AP600 test and analysis program (Proprietary) (WCAP #s given below) l WCAP-12665, Rev 1 WCAP-13267 WCAP-13294 WCAP-13284 WCAP-13342 WCAP-13290 WCAP-13234 WCAP-13307 WCAP-13328 WCAP-13286 WCAP-13330 WCAP-13292 WCAP-13345 WCAP-13305 WCAP-13296 WCAP-13351

'l WCAP-13298 WCAP-12667, Rev 1 l 1 i

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Depressurization Valve (DPV) Basis for Selection Failure rate reqNirement 1; 0.01 failures / valve per demand at 50% confidencelevel Mechanicalaspects of valve design assessed to have much lower failure probability than initiator / booster assemblies Over 70 booster (primer andpropellant) assemblies tested after radiation and thermal aging to demonstrate reliability Opening margin demonstrated with reduced strength booster assembly N_ o m., ww,., l'.*ile.1/ e st f, /

Depressurization Valve (DPV) Performance implications Effectoffailure to open SRV and DPV system are diverse and prevent excessive core heatup (best estimate) Effect of valve operation SRV and DPV operation is staggered Each DPV flow area is about 1/4 of the main steamline break area Inadvertent operation ALWR URD requires a probability < 10 /ranctor year Effects ofinadvertent operation minimized Thermal hydraulic effects similar to the small steamline break normally analyzed in the SSAR \\b S ,N ASil di??/92 [, l%ge IH of 6/ -. -. -... - - ~ -.

9 DPV - Summary GE has developed a reliable depressurization valve for use in the SBWR Primer andpropellant tests and the vendor shop tests have confirmed valve applicability Steam flow and reaction load tests provided valve induced blowdown loads forSBWRdesign l Afsterial qualification tests confirmed the longevity of nonmetallic valve componentsin the plant. Environmental qualification vibration tests completed the DPV qualification forSBWR - Reliability of mechanical components will be part of vendor purchase specification l h

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s _ Puy 1 !!!!!! jSBWR IC / '~ orain 1 - ~ ~ ljgl line Section A-A / w,,,, A C}._._.g-._. ._i_ _._._._.{_.g._ j- - ('} }L_._..q_ !__.4.._._(_L._._.g Cg._._.43_._. j..._ _ i .j.q_ _._._.4.{_._{_'_p._._.1.. g Q}_._}4_-_.Qfi ._._(_j_._._.g'j j i~ }}._._.g_._..L._ _._i_._.; .p-_- -- {._.{_}t._._._ ;. 'i l 4 i i i y \\ _ 'a _ im. _ sm x wa mer 7'A =j PANDA Passive Containment Cool r /M /9

ImportantPhysicalPhenomena Condensation heat transfer with non-condensable Venting ofnon-condensable gases Formation ofsteam-non-condensable interface in condenser Condensation, mixing and stratification in suppression pool niixing ofsteam and non-condensable in drywell i Recycling of noncondensables via vacuum breakers Flows driven bygravity andsmallpressure differences N-Od Boiling heat transfer on poolside of condenser s s asin.. I *.sq.e 11 of e./

v-Testing Programs - Basic Heat Transfer Data AflTProgram Performed steam-sir condensation experiments in a plenum geometry Performed steam-air experiments in a cooled-tube geometry University of California, Berkeley, Program - ' Performed steam-air condensation experiments in a tube geometry under natural circulation conditions Developed correlation for condensation heat transfer coefficient . depending on local mixture Reynolds number and non-condensabic mass fraction Incorporated " wet-bulb" technique for direct measurement oflocal noncondensable mass fraction M i v A i . ) A5114'?2e92 l'agee 11 eif te /

JAPC Test Program (Toshiba, GE, Hitachi) Purpose Confirm PCC heat transfer characteristics Clarify nitrogen purge mechanism Confirm integrated PCCS performance for post-LOCA containment cooling Provide data for calibration of analytical models Test facility \\' Full-scale in vertical direction M Linear scale 1:20 Integrated system test simulating all vessels and interconnecting ~~ piping a. A N 1 A'.i 4 4 W 9,5 f *.n)n 84 of es?

f []_ VCSystemPerformance TestFacility (38Pc) -J =. ' "y/C 1 .t 1/C - E

1. 2 4 -

W5 J ~ Poot sitan 4 g _ _ [_ - @__7_ g r SIC M (f' i os + 1 m ) i % l'.cpe l's ofte/ .~.

JAPC/Toshiba Separate Effects Test Data Comparisons Separate eninctb condensation heat transfer tests with variable inlet steam flowandnitogen mass fraction Effect of noncondensable measured on an integral basis for fulllength of condenser JR4CG modelbased on single tube data was used to simulate test Results indicate TRACG modelpredictions are in good agreement with data Conclusions I TRACG condenser model based on single tube data is a good basis for predicting condenser performance 's 3 as,n, .s. q ......i....,,,,

JAPC/Toshiba lategral Test Test Results Cons; ant-power tests confirmed mechanism of nitrogen venting from PCC Effect of vent line submergence and initial DW nitrogen inventory was studied Integrated system test for main steamline break simulation was performed ~0.7 atmosphere pressure reduction over a 17-hr period was observed TRACG Comparison Detailed TRACG model developed by GE (. m/, kG, a b,z.., M ./ TRACG calculations show reasonabic agreement with test data initial pressure peak conservatively predicted pressure decrease predicted accurate prediction of nitrogen flow between drywell/wetwell Pressure reduction caused bv return of nitrogen to drywell through vacuum breaker and heat losses

9

v. y. u.., u

i i. l~ i t i i a i i FIGURE 21 r i i DELETED DUE TO PROPRIETARY INFORMATION FOIA EX (b) (4) i i F 1 l I l l h I t i t i t I 1 i f 6 N ,. ~

Items Raisedin March 10 Letter ITEM

RESPONSE

1. Stabililty 1.1 Crediblq1ransinats with Physically impossible instability 1.2 Ge g durin u

inrGyse n-~ sn/g startup Start-up procedure change ~ n w, 1.3 Provi additional foreign data Addni data / qualification to be provided

2. Biased open check valve 2.1 Compreheqsive Aww/at<(.a/b. testing pryram gggggggg ygg,g,;;; pg,g gggquggg gag, upi,fe.

-~

3. Isolation condenseroperation 3.1 Program appears to be sufficient.

Agree 3.2 Review future test plans Agree 3.4 System interactions - DPV -Not used when DPV,oP,~en ( "'"',' / T ' ', i 3.5 System Interaction - IC pool Evaluated - no Problem ys y y; en w.w ,,a P. p.,9. e,/

Items Raised in March 10 Letter (cont.) ITEnt

RESPONSE

4. Passive containment cooling 4.1 Program is adequate-lowpress Agree integral test is ok 4.2 Review test plans for parameter Agree range 4.3 Review plans for severe Effects evaluated accident conditions 4.4 Long-term cooling Past programs demonstrate adequacy

5. Operation ofsquib DPV's 5.1 Insufficient tests to prove Testing for key new component reliability (explosive) proved reliabillty rest proven during man 0Tacture 5.2 SRV's may be unable to cover SRV's alone for short term job alone DPV's needed long term VN

\\Q .h i ANil 4W,9,6 l'.eq. s.e i t el s,/

ad Items Raised in March 10 Letter (cont.) Mgg

RESPONSE

5.3 Further testing of entire valve assembly needed Not needed for certiHcation

6. Baron distribution - SLCinjection 6.1 Demonstrate ABWR tests Agree adequate for SBWR

7. Systemsinteractions 7.1 Does IC/DPV common stub line affect blowdown No credit taken for IC in LOCA analysis 7.2 IC operations impact on PCCS Reduces containment pressure 7.3 Containment back pressure effect on blowdown Included in tests i

7.4 Vacuum breaker operation includedin tests Nh h' r %q Ahlt M.YU e...,,, i i..., e -

Items Raisedin March 10 Letter (cont.) WEhr

RESPONSE

ft e,., '. 7.5 Level fluctuations during Extensive test data available L,i b ' '., blowdown ~ 7.6 RPV, GDCS and suppression Interaction modcIIedin TRAC poolinteraction 1

7. 7 Non safety system impact Extensive test data available - past and S8WR 7.8 Limited /non representative SBWR tests - GISTand JAPC issues do integral tests not invalidate tests

, 7.9 PANDA tests may not be JAPC tests showedproof of principle / ' confirmatory" ~ p (',. e jy j a,i L,. / i / <...<.u.. ? 7.10 No additional high pressure Agree 'A ' ' ' ' ' y'I" ~ integral test ( t Ahlt 4??m? l'. g., b? i,f 6 /

4 Items Raisedin March 10 Letter ITEnt

RESPONSE

8. Severe accidenttests 8.1 Might require testing of Evaluations should be sufficient components 8.2 Debris coolability - sensitivily Agree studies, justification 8.3 Hydrogen impact on PCCS Agree performance - follow tests 8.4 Natural circulation and mixing in Effect of noncondensables on heat containments - testing in PANDA transfer has been tested 8.5 **uelcoolantinteraction including

- Existing data base should cover this corium spreading in pools 8.6 Containment bypass through Analysis to demonstrate bypass not PCCS p ible j (l A*.14 4 ??&* i..,..........,

I 1 i l 1 l FIGURES 27-32 l DELETED DUE TO PROPRIETARY INFORMATION FOIA EX (b) (4) i -r i F i l c 6 ( 5 t i i i l l a h d I i e c t i I P 'F t ? i I I f h .l t ~. ~-

O i LINX (Pool Mixing Test)# Objectives Examine WWresponse to heat / mass transfer associated with long-tenn containmentcooling Ewamine interaction between sub-surface condensation andpool mixing Examine influence of non-condensables on sub-surface condensation Evaluate means for enhancing pool mixing LINKTestFacility Open Plexiglass tanks for mixing visualization (llNX-1) Closedsteelpressure vessel (llNX-2) Sub-surface electricalheating Sub-surface injection ofsteanVnon-condensable mixtures Steam flow into closed vapor space above pool Heat conduction toAfrom closed vapor space above pool p

q LINX (Pool Mixing Test) (Cont'd.) llNX Testing Sub-surface heatingin open tanks -- Single Tank -- Connected Tanks Sub-surface injection in closed tanks -- Flow rata /non-condensable fraction -- Poolsub-cooling -- Ventpipe geometry Condensation on poolsurface and walls -- Nitrogen concentration -- Vesselwalltemperature -- Flowrate/non-condensable fraction o5 y it T G I j w ~ f yfM'104P01 tyn

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W 2 AIDA (Aerosol Transport / Deposition) Objective Investigate aerosol behavior in a condensing (PCC) environment ( AIDA TestFacility I Aerosolgeneration system (Csi, Cs0H, nfn0) l l Single tube, Mi height glass model for visualization of aerosol l behaviorin a condensing environment Simulation of upperplenum and. tubes of a PCC unit 1 M1 '.p... u\\ cA F-l' pf92104201 t;m -..~.....

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1 J :<;x ..,,,,a. i-PANDA (Integrated System Test) Objectives ConHanation of PCCS thermal-hydraulic margin with emphasis on multidimensional (parallel channel) effects Examine non-condensable composition effects PANDA TestFacility Full-scale elevation (excluding " dead" volumes) 1:2!F volume andpowerscales Annular DWand WW volumes simulated by interconnected cylindricalvessels Modulardesign for flexibility Provision forinternalheatsinks \\ Electrical heating to simulate decay heat t \\

a. -

2PCC units simulating S8WRPCC units 1ICunitsimulating2S8WRICunits I I pf92104201 tjm

7 PANDA-(Integrated System Test) (Cont'd.) PreliminaryPANDA TestMatrix(InitialConditions) Systempressure(aun) 2-4 DWnitrogen content (mass %) 5 - 40 WWwatertemperature(deg C) 30-60 Start time Scram + 1 hour i o OtherPANDA Test Variables RPV, DWand WWwaterlevels r ICpoolwatertemperature i i Symmetric / asymmetric steam flow to OW WitMwithout parallel ICS/PCCS operation w,: I pf 92104?Of t}rti

Je 4 O 4 G e PANDA l SBWR a 1- ',-;;;;;.\\ ,6' L.'] -l c poni )c Pooi .Y ',

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Schematic of the PANDA Experimental Facility l M // @ ,l

ALPHA Schedule Time Schedule 1990 1991 1992 1993 1994 1995 N /'. '.n, > ~ Project Dennition Phase W osseen ~ C.,:.:..^. Deep ""1 ;" : big iMstruction InstrumentationiDele Acquisillon c. ^ eeetps i meannessessen -_. CG.." ':-i.,, Planning of E=;1^.--4e Test . Detened W of 5---- ^ _.. y y -- s -~~~~^ ___ y 1 Data Evolustion Analytical Work Separate Effect Tests Mixing Aaesyne Espostnest 1 Aerosol Testing k s os . cone e, h s Esperheent j k( l Ano8ytical Weeti w-I pf92104?Of igm .. ~.. _.,. - -. - _ - -.... -._ _. - - _. _ - - -. ~ -., _, _ - _ _..

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9 m 4 t r l t 9 I FIGURE 46 DELETED DUE TO PROPRIETARY INFORMATION FOIA EX (b) (4) i 9 l t I ll t i I f i r I r I i l l i f 4 r ? 1 .. f i h t I L

l e l =% SBWR Te at Conditions. IC trif Five Test Types to be Studied Approrfmste Type nurnber of cyckas

1. *Normar IC Operaton 19

2. *Normar IC Operaton + Periormance Data 20 3 'Normar IC Operaton + Non-Condensable Gases 6

4. Reactor Heatup/Cooioown w o IC Operaton 85 a 5 ATWS 1 i A full range of SBWR transtant mnditons will be simulated l WS9 fB '/ SBWR Schedule tf i Activtry: 1992 1993 1994 l Hx Fabncaton l 4 i IMHamuelm installaton & i Shakedown sun Testng CD i i 1I55 sulumu Test Report C aus i O PCC Em IC NB 'O [.

)

T/H RESEARCH ON SBWR S, TART.ED AT INEL.IN CY 1989' REPORTS WERE PRODUCED ON SBWR DESIGN REVIEW SURVEY OF EXPERIMENTAL DATA BASE FOR SBWR-USER NEED LETTERS FROM NRR, AND RES RESPONSE 1. RESEARCH USER NEEDS FOR ADVANCED PASSIVE REACTORS, T. MURLEY TO E. BECKJORD, ' DECEMBER 11, 1990 i NRR E50 RES RESPONSES INDEPENDENT ANALYTICAL "GET WELL" PLAN FOR CAPABILITY RELAP5; CODES ON WORKSTATIONS (RELAP5, TRAC-8, AND RAMONA) ASSESS IMPORTANT REVIEW DESIGN AND PHENOMENA EXPECTED PERFORMANCE;- PERFORM SBWR PLANT ANALYSES ASSESS ADEQUACY OF SURVEY OF DATA BASE: VENDOR TEST PROGRAMS JOINT RES/NRR PLAN-OF 4/0I/92; INITIATE ANALYSIS OF SBWR-DATA UPDATE. ANALYSIS RELAPS CODES AND-MODELS RAMONA (TRAC-BWR AS BACK-UP) REC 0f94END-EXPERIMENTAL INITIATE ANALYSIS OF PROGRAMS AND ADDITIONAL PANDA TESTS GE SETS 58 M ' v2-d. ADDITIONAL TEST FACILITIES LOOP TO CONFIRM GDCS F / REQUIRED? TESTS IN GIST ADDRESS SCALING ISSUES SCALING REPORT ISSUED: SPECIFIC STUDIES-IN 50W'S j f / FOR EACH TEST FACILITY-3 4. / QI i Q

~

• i s

i NRR USER NEEDS (CONTINUED) 2. NEED FOR IMPROVED BWR CALCULATION CAPABILITY FOR ADVANCED i REACTOR STABILITY AND TRANSIENT RESPONSE STUDIES, i A. THADANI, NRR, TO B. SHERON, RES, FEBRUARY 19, 1991. 1 ALSO, MEETING WITH RES REGARDING BWR CALCULATION CAPABILITY, i A. THADANI, NRR, TO B. SHERON, RES, SEPTEMBER 9,.1991. l l NRR NEED RES RESPONSES i SBWR CORE SIMULATOR WITH UPGRADE RAMONA i 3-D KINETICS AND MULTIPLE l T/H CHANNELS 3. SELECTION OF COMPUTER CODE FOR SBWR ANALYSIS, A. THADANI, NRR, TO B. SHERON, RES, MAY 30, 1991. i NRR NEED RES RESPONSES EVALUATE RELAPS FOR SBWR INITIAL EVALUATION ANALYSIS FAVORABLE MODIFY RELAP5 FOR SBWR INITIATING CODE 'I ANALYSIS IF EVALUATION IS MODIFICATIONS AFTER FAVORABLE "GET WELL" PLAN IS COMPLETED MODIFY TRAC-BWR FOR SBWR KEEPING TRAC-BWR ANALYSIS IF EVALUATION IS AVAILABLE AS A BACK-UP J UNFAVORABLE I i a-=

l ~ s i d i 1 NRC RESEARCH PROGRAMS FOR SBWR l SBWR LOOP PLANT ANALYSES WITH RELAPS j CODE IMPROVEMENTS FOR SBWR l RELAP5 RAMONA BACK-UP CODE FOR SBWR ANALYSIS: TRAC-BWR ANALYSIS OF GE SEPARATE EFFECTS TESTS 8 ANALYSIS OF PANDA TEST FACILITY t I ) [ f i t ~ I i 4 i l I i "A' / i l 5ECtLS

~ iS_WE LOOP W REQUEST FOR RFP SUBMITTED TO SCRB ON APRIL 9, 1991 SCRB REQUESTED INFORMATION PAPER TO COMMISSION, WITH NRR CONCURRENCE COMMISSION PAPER IS IN CONCURRENCE ~ _ _ _ _. _ PLANT ANALYSES WITH RELAP5 INPUT DECK BEING PREPARED ANALYSES T0_STARI_.IN _TWO MONTHS _ CODE IMPROVEMENTS FOR SBWR I RELAPS "GET-WELL" PLAN BEING COMPLETED IM 8 7 T DEVELOPMENTAL ASSESSMENT WILL START SBWR MODELING INITIATED BORON TRANSPORT CONDENSATION WITH NON-CONDENSIBLES ~- RAMONA CONTRACTOR HAS PREPARED PLAN FOR IMPROVING MODELS. EXAMPLES OF NEEDED MODELS ARE: CHIMNEY (RISER), BORON TRANSPORT, ISOLATION CONDENSER, ADS, GDCS SINCE THE MAIN USE OF RAMONA WILL BE TO CALCULATE REACTIVITY TRANSIENTS IN THE SBWR CDRE, THE MODELING OF EX-CORE COMPONENTS OR PHENOMENA CAN BE SIMPLIFIED. CLOSE COORDINATION k!ITH THE INEL WORK ON RELAPS SSWR MODEL DEVELOPMENT

BACK-UP CODE FOR SBWR ANALYSIS: TRAC-BWR DOCUMENTATION WILL BE COMPLETED BY INEL ON SEPTEMBER 1992 RFP FOR CODE MAINTENANCE IN DISCUSSION PHASE WITH SIDDERS 50W HAS GENERAL TASK TO PERFORM CALCULATIONS FOR NRC. ANALYSIS OF GE SETS 50W IS NOT YET PREPARED ANALYSIS OF PANDA TEST FACILITY S0W HAS BEEN PREPARED AND IS UNDER MANAGEMENT REVIEW r s Y ~-

THE NRC-FUNDED INTEGRAL SBWR TEST FACILITY A LOW-PRESSURE SCALED INTEGRAL TEST FACILITY INCLUDING

WATER, STEAM, AND NONCONDENSIBLE WITH:

o VESSEL WITH ELECTRICALLY-HEATED CORE o DRYWELL AND WETWELL INCLUDING SUPPRESSION POOL o GRAVITY-DRIVEN COOLING SYSTEM (GDCS) o PASSIVE CONTAINMENT COOLING SYSTEM (PCCS) o ISOLATION CONDENSER (IC) SYSTEM: o ASSOCIATED VALVES AND PIPING i o INSTRUMENTATION FOR PROVIDING MEASUREMENTS UNDER VARIOUS ACCIDENTS AND TRANSIENTS O I i j' i 9

7.. c SCHEDULE AND COST ESTIMATES FOR THE NRC TEST' FACILITY bl MILESTONES COMPLETION DATE COST ESTIMATE ($K). i 1. PLACE RFP IN COMMERCE BUSINESS 5/15/92-j DAILY ~ 2. SELECT ChiTRACTOR 9/30/92 3. DESIGN' FACILITY 4/30/93 300 4. CONSTRUCT FACILITY 3/31/94 1200 5. SHAKEDOWN FACILITY, ,6/30/94-200 . / t u (. (, 6. . PERFORM EXPERIMENTS 5/31/96/<' d"' # D 600 2300 e 's, O_: O . ~. '

I' G. WORMAN LAUBEN DIVISION OF SYSTEMS RESEARCH OFFICE OF NUCLEAR REGULATORY RESEARCH 1. RELAP5 MOD 3 STATUS SHORTCOMINGS IN INITIAL siRSION PREVENTED EFFICIENT USE MAJOR PROBLEMS IN CODE HAVE BEEN IDENTIFIED BY SEARCHING FOR ROOT CAUSES MAJOR PROBLEMS IDENTIFIED IN SELECTED ANALYbES WILL BE CORRECIED BY 5/1_/92 RELAPS REVIEWED TO DETERMINE IMPORTANT MODEL IMPROVEMENTS NEEDED FOR SBWR ANALYSES IN MAY, 1992, BEGIN PARALLEL DEVELOPMENTAL ASSESSMENT USING WIDE RANGE OF TEST Cr$*5 ADDING HIGH PRIORITY MODELS FOR SBWR AND AP600 ANALYSES EVALUATE POSSIBLE MODEL CHANGES APPLICABLE TO OTHER LWR ISSUES 2. PROPOSED H0DELING IMPROVEMENTS FOR SBWR EXPECTED IMPROVEMENTS NONCONDENSIBLE EFFECTS ON CONDENSATION FLOW PATH OBSTRUCTION CONDENSATION IN TUBES OF PCCS AND IC BORON TRANSPORT LOW FLOWS, THERMAL STRATIFICATION, RECIRCULATION NUMERICAL DIFFUSION IN RELAPS GIVES INACCURATE CONCENTRAT11N BREAK ENERGY BALANCE FLUID ENERGY IN A DOWNSTREAM VOLUME MAY BE CALCULATED INACCURATELY IF oP BETWEEN CELLS IS LARGE (IMPORTANT FOR CONTAINMENT MODELING) STEAM SEPARATOR PERFORKANCE CURRENT IDEALIZED MODEL WILL NOT GIVE GOOD RESULTS FOR ALL TRANSIENTS WILL USE FIRST PRINCIPLES MODEL THERMAL STRATIFICATION INACCURATE CONCENSATION RATES CALCULATED IN ISOLATION CONDENSER POOLS NEW MODELS REQUIRED: MUST AL50 REVISE HOW RELAP CALCULATES INTERACTION BETWEEN VOLUMES CONTAINMENT MODELING CONTAINMEhT IMPORTANT TO PASSIVE SAFETY SYSTEM PERFORMANCE MODELING APPROACH WTLL BE EItT(r 7 NED '}}