ML20138B885

Requests That Proprietary Presentation Matl from 970312 Meeting Re Long Term Cooling Be Withheld Per 10CFR2.790

ML20138B885
Person / Time
Site:	05200003
Issue date:	04/23/1997
From:	Mcintyre B WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
To:	Quay T NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML19355F103	List: ML20138B885 NSD-NRC-97-5081, Forwards Proprietary Presentation Matl from 970312 Meeting W/Staff Re Long Term Cooling.Proprietary Encl Withheld,Per 10CFR2.790.Nonproprietary Presentation Also Encl
References
AW-97-1099, NUDOCS 9704290299
Download: ML20138B885 (83)

Text

O Westinghcuse Energy Systems yn"yjenneania m30 a355 Electric Corporation AW-97-1099 April 23,1997 Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION: MR. T. R. QUAY APPLICATION FOR WITilllOLDING PROPRIETARY INFORMATION FROM PUBLIC DISCLOSURE

SUBJECT:

PRESENTATION MATERIAL FROM MARCil 12,1997 LONG TERM COOLING MEETING

Dear Mr. Quay:

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 version of the subject report in conformance with 10CFR Section 2.790, Affidavit AW-97-1099 accompanies this appli.:ation for withholding setting forth the basis on which the identified proprietary information may be w.thheld 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. l l

Correspondence with respect to this application for withholding or the accompanying affidavit should l reference AW-97-1099 and should be addressed to the undersigned.

Very truly yours, Brian A. A cintyre, Manager Advanced Plant Safety and Licensing

.__ jml ___

cci Kevin Bohrer NRC OWFN - MS 12E20 9704290299 970423 PDR ADOCK 05200003 A PDR ,

L.

AW-97-1099 AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA:

1 ss v

COUNTY OF ALLEGilENY: ,

Before me, the undersigned authority, personally appeared Brian A. McIntyre, who, being by me l

duly sworn according to law, deposes and says that he is authorized to execute this Affidavit on behalf l l

of Westinghouse Electric Corporation (" Westinghouse") and that the averments of fact set forth in this Affidavit are true and correct to the best of his knowledge, information, and belief:

f r,.

Brian A. McIntyre, Manager Advanced Plant Safety and Licensing Sworn to and subscribed before n e this // g day I

of /M '

M Notarial Seal Janet A. Schwab. Notary Public

/ Monroewfle Boro. Alk4gheny County p My Commission Erpires May 22,2000

, f a Member. Pennsylvana Assacanoo nt Nses Notary Pt.blic wn

. AW-97-1099 t

(1) I am Manager, Advanced Plant Safety And Licensing, in the Advanced Technology Business l Area, 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 proceeding s, and am authorized to apply for its withholding on behalf of the Westinghouse Energy Systems Business Unit.

(2) I am making this Affidavit in conformance with the provisions of 10CFR Section 2.790 of the l Commission's regulations and in conjunction with the Westinghouse application for ,

i 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 detennine 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.

l l

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:

ll68 A L

. AW-97-1099 (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 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.

1 It reveals cost or price information, production capacities, budget levels, or  !

(d) 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 l Westinghouse. j I

I (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 .

i disclosure to protect the Westinghouse competitive position. l (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.

Il68 A A

4

, AW-97-1099 (c) Use by our competitor would put Westinghouse at a competitive disadvantage

] by reducing his expenditure of resources at our expense.

(d) Each component of proprietary information pertincnt to a particular competitive advantage is potentially as valuable as the total competitive advantage. If competitors acquire components of proprietary information, any one component may be the key to the entire puzzle, thereby depriving Westinghouse of a competitive advantage.

(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.

(f) The Westinghouse capacity to invest corporate assets in research and development depends upon the success in obtaining and maintaining a competitive advantage.

i (iii) The information is being transmitted to the Commission in confidence and, under the provisions of 10CFR Section 2.790, 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. 3 1

(v) Enclosed is Letter NSD-NRC-97-5081, April 23,1997 being transmitted by Westinghouse Electric Corporation (W) letter and Application for Withholding Proprietary Information from Public Disclosure, Brian A. McIntyre (W), 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.

3168 A L

AW 97-1099 l This information is part of that which will enable Westinghouse to:

I j (a) Demonstrate the design and safety of the AP600 Passive Safety Systems.

i (b) Establish applicable verification testing methods.

l I Design Advanced Nuclear Power Plants that meet NRC requirements.

(c) l i

(d) Establish technical and licensing approaches for the AP600 that will ultimately result in a certified design. I (e) Assist customers in obtaining NRC approval for future plants. ,

i Further this information has substantial commercial value as follows:

(a) Westinghouse plans to sell the use of similar information to its customers for l l

purposes of meeting NRC requirements for advanced plant licenses.

(b) Westinghouse can sell support and defense of the technology to its customers in the licensing process. '

l Public disclosure of this proprietary information is likely to cause substantial harm to 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 requirements for licensing documentation without purchasing the right to use the  !

information.

l 1

I I

m4A

1

. AW-97-1099 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 efTort i

and the expenditure of a considerable sum of money.

In order for competitors of Westinghouse to duplicate this information, similar technical programs would have to be performed and a significant manpower ellbrt, having the requisite talent and experience, would have to be expended for developing analytical methods and receiving NRC approval fbr those methods.

Further the deponent sayeth not, l s

1108A

. . - . . _ - _ _ _ _ . . - . -. - . - - = --. . _ . -.

Enclosure 2 to Westinghouse Letter NSD-NRC-97-5081 April 23,1997 r

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AP600 LONG TERM COOLING ANALYSIS

I 4

AGENDA March 12,1997 Wednesday,12:00 pm  !

Westinghouse Rockville Office LONG TERM COOLING NRC/W MEETING

1. Introduction (Novendstern)

2. Analysis Approach (Hochreiter)

3. PIRT(Hochreiter)

4. Summary of Westinghouse Topical Report (Garner)

5. Recent Extended Time Calculation Results (Garner)

6. WC/T Plant Model (Kemper)

7. Summary (NRC/W)

8. ACRS Agenda (Hochreiter) l l

. INTRODUCTION AP600 LONG TERM COOLING IS UNIQUE QUASI-STEADY GRAVITY INJECTION FOR LONG PERIODS (INDEFINITY UNTIL THE PLANT IS RECOVERED)

. TWO INJECTION PHASES:

INITIAL INJECTION IS FROM IRWST (HIGHER HEAD WITH HIGHER FLOWS, WHEN DECAY POWER IS HIGHER RECIRCULATION INJECTION FROM S~ UMP WITH LOWER FLOWS WHEN DECAY POWER IS LOWER

. REACTOR CAVITY BECOMES FLOODED, COVERS HOT AND COLD LEGS

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AP600 SBLOCA Scenario 1  :  !

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1 5 Figure 1-1 AP600 Small-Break LOCA and LTC Scenario L .

WCAP-14776 REVISloN: O ao164=-1.wyt.th 110496 1 10 November 1996

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, . INTRODUCTION - CON'T LONG TERM COOLING IS COMMON END POINT FOR ANY TRANSIENT WHICH ACTIVITATES ADS 1-3, OR THE RCS IS DEPRESSURIZED (SBLOCA, LBLOCA).  ;

OBJECTIVES OF THE AP600 PLANT ANALYSIS IS TO VERIFY '

THAT AP600 PASSIVE SAFETY SYSTEMS: t

. MAINTAIN CORE COOLABILITY INDEFINITY t i

HAVE THE SAME PEDIGREE AS SIMILAR LONG TERM  ;

COOLING SYSTEMS ON CURRENT OPERATING PLANTS.  !

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. LONG TERM ANALYSIS METHOD WCOBRNTRAC WAS SELECTED FOR AP600 LONG TERM COOLING ANALYSIS

. ACCURATE LOW PRESSURE CALCULATIONS ARE NEEDED

. APPENDIX K TYPE CALCULATIONS WERE AGREED UPON WITH THE NRC

. IT WAS DESIRABLE TO USE AN ANALYSIS METHOD WHICH THE NRC WAS FAMILIAR WITH WCOBRA/ TRAC HAS BEEN VALIDATED FOR LOW PRESSURE GRAVITY INJECTION SITUATIONS (CCTF AND SCTF TESTS)

AND IS MOST SUITABLE FOR AP600 LTC G

S

. - - _ - - - - - - -- _ .* --w

. LONG TERM COOLING ANALYSIS METHOD - CON'T i

SINCE THE LONG TERM COOLING TRANSIENTS ARE LONG QUASI-STEADY FLOW SITUATIONS, A " WINDOW MODE" -l ANALYSIS METHOD HAS BEEN ADOPTED -

. THE " WINDOWS" REPRESENT SELECTED TIME PERIODS OF THE FULL TRANSIENT TO EXAMINE TIME PERIODS WHICH ARE MOST CHALLENGING FOR LTC

. " WINDOW " CALCULATIONS ARE TYPICALLY 1000 - 1500 SECONDS IN LENGTH FOR THE PLANT i

L

DURING THE LTC TRANSIENT, THE PLANT PRIMARY SYSTEM IS  :

IN A ONCE THROUGH COOLING MODE WITH INJECTION INTO '

THE DVI LINE AND VENTING OUT THE ADS STAGE 4 VALVES <

THE REACTOR SYSTEM TRANSIT TIME IS APPROXIMATELY 300 - 700 SECONDS DEPENDING ON THE TIME PERIOD ,

. SINCE THE WINDOW MODE CALCULATIONS ARE FOR LONGER TIME PERIODS, THE RESULTING QUASI-STEADY I STATE FOR THE REACTOR SYSTEM IS DRIVEN BY THE l IMPOSED BOUNDARY CONDITIONS, NOT THE INITIAL CONDITIONS THE IN'ITIAL CONDITIONS ~SUCH AS VESSEL LEVELS OR MASS DISTRIBUTION WILL BE SWEPT AWAY BY THE IMPOSED BOUNDARY CONDITIONS OF,

~

DVI LINE FLOW CORE POWER  :

i SYSTEM PRESSURE

AS A RESULT, A REASONABLE SET OF INITIAL CONDITIONS WILL BE ADEQUATE TO INITIALIZE A WINDOW MODE CALCULATION SINCE AT THE END OF 1000 - 1500 SECONDS THE RESULTS WILL REFLECT THE IMPOSED BOUNDARY CONDITIONS.

IN THIS FASHION, THE LONG TIME PERIODS OF THE LTC TRANSIENT CAN BE DIVIDED INTO SHORTER TRANSIENTS WHICH CAPTURE THE MOST IMPORTANT TIME PERIODS TO SHOW ADEQUATE CORE COOLING SEVERAL DIFFERENT CALCULATIOlC, ARE PERFORMED TO EXAMINE DIFFERENT LTC SITUATIONS TO ASSURE ADEQUATE CORE COOLING

_ _ . _ _ _ _ _ _ _ _ _ _ _ . _ _ _ - - _ _ _ . _ . _ _ . ____ _ .__ ___ _ _ _______-_______m__.__ . m. _ _ s

% g. 4 _ A am . %,a a. %- A . L AP600 LONG TERM COOLING PIRT 9

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. AP600 LONG TERM COOLING PIRT f i

LTC PIRT WAS DEVELOPED AND REVIEWED AT '

WESTINGHOUSE AND HAS BEEN SUBMITTED TO THE NRC AS '

PART OF THE LTC WCAP  !

COMMENTS HAVd BEEN RECEIVED FROM THE NRC AND ITS CONSULTANTS AND HAVE BEEN INCLUDED IN THE FINAL LTC PIRT (MARCH 1996 MEETING) i SOME PHENOMENA WHICH WERE INITIALLY RANKED ,

HIGHER ARE NOW RANKED LOWER BASED ON THE OSU TEST ANALYSIS AND OSU SIMULATIONS l.

3,

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l TABLE 11 PHENOMENA IDENTIFICATION RANKING TABLE FOR AP600 LOCA LTC TRANSIENT (Rev.1)

Component IRWST Sump l Phenomenon Injection"' Injection'"

l Break 1

Cntical flow M N/A l Subsonic flow M L l

l ADS Stages 1 to 3 t i

Critical flow M N/A Subsonic flow M L l Two-phase pressure drop L L Valve loss coefficients M/L L Single-phase pressure drop L L Vessel / Core Decay heat H H Flow resistance L L Flashing N/A N/A Wall-stored energy M M Natural circulation flow and heat transfer M M Mixture level mass inventory H H Pressunzer Pressurizer fluid level L N/A Wall-stored heat L N/A Pressunzer Surge Line Pressure drop / flow regime L L Downcomer/ Lower Plenum Pressure H H Liquid level H H-Condensation M M Upper Head Liquid level N/A N/A

, Flow through downcomer top nozzles M M .

WCAP 14776 REVISION: 0 m:ul64. wpt:Ib-lios96 I 17 November 1996 1

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FINrt, TABLE 1 1 (Cont) d Q*

PliENOMENA IDENTIFICATION RANKING TABLE FOR AP600 LOCA LTC TRANSIENT (Rev.1) '

l' Component IRWST Sump Phenomenon Injection (" Injection'"

Upper Plenum Liquid level H H Entrainment/deentrainment M M ,

Cold Legs Condensation L L Separation at balance line tee L L l Steam Generator 26 natural circulation N/A N/A Steam generator heat transfer IJNA'" N/A Secondary conditions IJNA* N/A ~

Hot Leg Flow pattern transition H/M H/M Separation at ADS 4 tee H/M H/M ADS 4 I Cntical flow I H N/A Subsonic flow H H CMT Recirculation injection N/A N/A Gravity draining injection L L Vapor condensation rate L L CMT Balance Lines Pressun drop N/A N/A Flow composition L L Accumulators I Noncondensible gas entrainment N/A N/A IRWST Gravity draining injection H M I Vapor condensation rate L L Temperature distribution M M I

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WCAP 14776 mM164w i.wyt:1b-110596 REV1510N: 0 1-8 November 1996

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l TABLE 11 (Cont)

PHENOMENA IDENTIFICATION RANKING TABLE FOR AP600 LOCA LTC TRANSIENT (Rev.1)

Component IRWST Sump Phenomenon Injection'" Injection'"

DVI Line Pressure drop H H PRHR 1

i Liquid natural circulacon flow and heat transfer N/A N/A l

Sump  !

i .

Gravity draining injection N/A H l

I Level N/A H Temperature N/A H i

l Note:

1. H = High -

1 M = Medium l L = Low

)

N/A = Not Applicable  !

l 2.

The raniangs for steam generator heat transfer and secondary conditions are Low for IRWST injection after

] a large break and Not Applicable for IRWST injection after a small break.

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l l WCAP-14776 REVISION: 0

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mM164=-1 wpf.ib-110596 19 November 1996

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WC/T Code Validation for j l

AP600 Long-Term Cooling l

- Overview of OSU Test Data

- Summary of Westinghouse Topical Report i

- Recent Extended Time Calculational Results j

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March 12,1997 i

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Overview of OSU Test Data

- Test to Test Similarities  ;

- Significant Flow Rates .

- Vessel Pressure Variations i l

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OSU Measured Flow Rates at End of IRWST Draindown (a,b,c)

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Test / Time SB01/ SB10/ SB12 / SB23/

I 14,500 see 14,0500 sec 9,000 sec 14.500 sec  :

DVl-1 (lb/sec)

)

DVI-2 (Ib/sec)

Total Vessel inflow (Ib/sec)

Break Flow (Ib/sec) )

ADS 1,2,3 Flow (Ib/sec) 5 ADS 41 Flow (Ib/sec)

ADS 4 2 Flow (Ib/sec)

Total Vessel outflow (Ib/sec)

l REACTOR VESSEL PRESSURES DURING IRWST DRAINING OSU Test abo 1, sb12. sb18, & sb23 (a,b.c) n l

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REACTOR VESSEL PRESSURES DURING IRWST ORAINING i

OSU Test sb18,2" Cold Leg Break (a,b,c) l l

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.i WC/T Code Validation for AP600 Lona Term Coolina Analysis Letter Rpt. ,

WCAP-14776 NSD/NRC-97-5014

@ WC/T Performance in Window Mode Calculations WC/T Performance in Window Mode Calculations @

l

1. Initial Condition Sensitivity 1. ExtendedTime Sensitivity

2. Boundary Cond. 1 Sensitivity

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WC/T Summary .

WC/T LTC ' Validation of WC/T l Loop and Vessel M for AP600 Long Term Q Applicability for Plant l

Models i Cooling Analysis Calculations Letter Rpt.

WCAP-14776 NSD/NRC 97-5014 WCfr and OSU Data WC/T and OSU Data Comparisons of Comparisons of

@ $801,SB10, B12 & SB23 SB01 & SB10

1. 3000 Sec.

Windows

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- Loop Model

- Vessel Model .

- Boundary Condition inputs

- Initial Condition inputs O

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OSU - WCfr LONG-TERM COOLING BOUNDARY CONDITIONS I i

sbO1 sb10 sb12 sb23 Source of data No. Condetson

1. Calc initiation Time (sec) ,

2. IRWST Level (Rel. to drain) (in) i

3. IRWST Temperature (*F)

4. Sump Level (Rel. to drain) (en)

5. Sump Temperature ("F)

6. Break Separator Level (in)

7. Break Separator Temp (*F) l

8. Core Makeup Tank 1 Flow (ib/sec)

9. Core Makeup Tank 1 Temp ("F)

10. Core Makeup Tank 2 Flow (ib/sec)

11. Core Makeup Tank 2 Temp ("F)

12. SG Secondary Side Temp (F)

13. SG Secondary Side Pres,s (pssa)

14. Core Power Factor ,

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OSU - WC/T LONG-TERM COOLING INITIAL CONDITIONS

_ l l ._. . . . _

Source of data sbO1 sb10 sb12 sb23 No. Condition

1. Time of Start of IRWST (sec)

2. Upper Plenum Level (sn)

3. Downcomer Level (in)

4. Downcomer Flu.d Temp. ("F)

5. Vessel Wall Metal Temp. ("F)

6. Core Liquid Temp. ("F)

7. Initial Fuel Rod Temp. ("F)

8. 1-D Hot Leg Level (in)

9. SG Channel Head Level (in)

10. Cold Leg Level (in)

11. Pressurizer Level (in)

12. Surge Line Level (en)

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WC/T VALIDATION CALCULATIONS FOR l LONG-TERM COOLING ANALYSIS l

l

1. WC/T Initial Condition Convergence - WCAP-14776 1

- Fixed boundary conditions

- Varied individually vessel initial conditions

- Vessel liquid level Downcomer temperature

- Tests SB01 and SB10 ,

I l

2. WC/T Extended Time Calculation Convergence - NSD/NRC-97 5014

- Reference calc., SB01,1260 sec. to 4600 sec.

- Comparison calc., SB01,3600 sec. to 4600 sec.

- Identical vessel initial conditions -

- Appropriate, time dependent boundary conditions

3. WC/T Boundary Condition Convergence - NSD/NRC-97 5014

- Reference calc., SB01,8000 sec. to 9000 sec.

- Comparison calc., SB01,8000 sec. to 9000 sec.

- IRWST level raised 2.5 ft for 200 sec. (3600 sec level)

- Core Power raised 30% for 200 sec. (3600 sec value)

- S.G. Temp. raised 45 F for 200 sec. (3600 sec value)

- Identical vessel initial conditions (8000 sec. value)

4. WC/T Comparison with OSU Test Data

- WCAP-14776 l

- SB01,2' CL Break,14,000 sec, to 15,000 sec. l

- SB10, CMT Balance Line Brk.,13,500 sec. to 14,500 sec. l

- SB12, DEG DVI Line Brk., 8,500 sec. to 9,500 sec.

- SB23,1/2' CL Break,14,000 sec. to 15,000 sec.

- NSD/NRC-97-5014

- SB01, 2' CL Break.1.260 sec. to 4,600 sec.

- SB01,2' CL Break, 8,00 sec. to 9,000 sec.

- SB10, CMT Balance Line Brk.,13,500 sec. to 16,500 sec.

WC/T Code Validation for AP600 Lona Term Coolina Analysis Letter Rpt.

WCAP 14776 NSD/NRC 97-5014  ;

WC/T Performance in WC/T Performance in C2l Window Mode Calculations Window Mode Calculations @

1. Initial Condition Sensitivity 1. ExtendedTime Sensitivity

2. Boundary Cond.

Sensitivity O WC/T Summary .

WC/T LTC  ! Validation of WC/T Loop and Vessel M for [ Applicability Models i AP600 Long Term for Plant Cooling Analysis Calculations Letter Rpt.

.. WCAP-14776 NSD/NRC 97 5014 WC/T and OSU Data WC/T and OSU Data Comparisons of Comparisons of 5801, SB10. SB01 & SB10 @

@ B12 & SB23 1. 3000 Sec.

Windows

? ,

b Sensitivity to Initial Conditions - SB10 Initial Vessel Liquid Level Sensitivity i

- Upper Plenum Collapsed Liquid Level j

- Downcomer Collapsed Liquid Level 1 DVl-1 Injection Flow I i

ads 4-1 Flow  :

l Initial Downcomer Liquid Temperature Sensitivity 1

- Upper Plenum Collapsed Liquid Level

- Downcomer Collapsed Liquid Level DVI-1 Injection Flow ADS 4-1 Flow

- -. . _ - -. . - . - . . - . - . . . . _ _ . - . _ _ . . - _ . - . . . - . . - _ . _ . . - = . . . . . . . . - _ .

r f

I The Following Figures are in the Proprietary Version of this Report Figure 3-22 Figure 3-36 Figure 3-41 Figure 3-47 Figure 3-54 Figure 3-52 Figure 3-57 Figure 3-63 r

I f

I l  !

s WC/T Code Validation for AP600 Lona Term Coolina Analysis Letter Rpt.

WCAP-14776 NSD/NRC-97 5014

@ WC/T Pedormance in Window Mode Calculations WC/T Pedormance in Window Mode Calculations

1. Initial Condition Sensitivity 1. ExtendedTime Sensitivity

2. Boundary Cond.

Sensitivity O W C/T Summary -

WC/T LTC ' Validation of W C/r Loop and Vessel 5 for A Applicability Models i AP600 Long Term for Plant Cooling Analysis Calculations l

Letter Apt.

WCAP-14776 NSD/NRC 97-5014 WC/T and OSU Data WC/T and OSU Data Comparisons of Comparisons of

@ SB01,SB10. SB01 & SB10 @

B12 & $823 1. 3000 Sec.

Windows

1 .:

l l

WC/T Extended Time Convergence - SB01 Upper Plenum Collapsed Liquid Level

- Downcomer Collapsed Liquid Level 1

- Core Collapsed Liquid Level ,

DVl-1 injection Flow I

Integrated DVI-1 Flow

1 ADS 4-1 Flow

1 Int'egrated ADS 4-1 Flow .

l k Start of IRWST Draindown

-e

> l

? /

0 2 l /

3

$ l ,' ,

l /

I e

.(---

U Identical Initial Vessel Conditions E

c i

1260 3600 4600 Time (sec) l '

l l

l l

J The Following Figures are in the Proprietary Version of this Report Figure 2.1-4 i

Figure 2.1-2 Figure 2.1-3 Figure 2.1-7 i t

Figure 2.1-8 i i

Figure 2.1-13 Figure 2.1-14 t

i l

r 4

I w

- W I i

i WC/T Boundary Condition Convergence - SB01

- Upper Plenum Collapsed Liquid Level Downcomer Collapsed Liquid Level Core Collapsed Liquid Level DVl-1 Injection Flow l

Integrated DVl-1 Flow i

ADS 4-1 Flow Integrated ADS 4-1 Flow 4

c. .

j E. Ref. Secondary Temp. + 45 F i

& i

JJ '

O 1 I

e m

' i l

l R --

Ref. Decay Heat + 30%

1 E

e

'N 0

4 g Ref. Level + 2.5' l

e 3 h o

e 8000 8200 8300 9000 4

Time (sec) d 1

1

The Following Figures are in the Proprietary Version of this Report t

Figure 2.2-4 Figure 2.2-2 l

Figure 2.2-3 Figure 2.2-7 l Figure 2.2-8  !

Figure 2.2-13 Figure 2.2-14

')

WC/T Code Validation for AP600 Lona Term Coolina Analysis _

Letter Rpt.

WCAP 14776 NSD/NRC 97-5014 WC/T Performance in WC/T Performance in

@ Window Mode Calculations Window Mode Calculations @

1. Initial Condition Sensitivity 1. ExtendedTime Sensitivity 4 2. Boundary Cond.  :

Sensitivity l

' i l

O WC/T Summary WC/T LTC '

Validation of WCrr Loop and Vessel 5 for AP600 Long Term

-5 Applicability for Plant I

- Models i Cooling Analysis Calculations i

l I l Letter Rpt.

WCAP 14776 NSD/NRC 97-5014 WC/T and OSU Data WC/T and OSU Data Comparisons of Comparisons of O4 SB01, SB10, SB01 & SB10 @

B12 & SB23 1. 3000 Sec.

Windows i

1 3

l J l t

! l I

Test Data Comparisons - SB01 1

- Upper Plenum Collapsed Liquid Level

- Downcomer Collapsed Liquid Level Total DVl-1 Injection Flow ADS 4-1 Flow l

l l

l

. . . . _ . . ._ _ . . _ . - . = _ _ _ _ _ . . . _ . _ _ _ _ _ . . _ . _ _ . . _ _ _ _ . _ _ . . - - _ . _ _ _ . _ . - . _ _ _ - . . . _ . . _ _ .__ ._.. _. .__. .__

l i

t i

1 1

F The Following Figures are in the Proprietary Version of this Report t

Figure 5.1-23  ;

Figure 5.1-24 Figure 5.1-7 t

t Figure 5.1-17  :

?

f i

l t

i 6

P G

. _ _ . _ . _ _ _ . _ _ . _ _ _ _ _ _ _ _ . _ _ . _ _ . - _ _ _ _ _ _ _ _ _ _ 2 ___ _ _ ___ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ . _- - - ___

_ * ~ _ _ - _ - -

Jy WC/T Code Validation for AP600 Lona Term Coolina Analysis l l

Letter Rpt.

WCAP-14776 NSD/NRC-97 5014 -

WC/T Performance in WC/T Performance in

@ Window Mode Calculations

1. Initial Condition Sensitivity Window Mode Calculations

1. ExtendedTime Sensitivity

2. Boundary Cond. .

Sensitivity l l

l O WC/T Summary .

WC/T LTC '

Validation of WC/T Loop and Vessel M for AP600 Long Term 7 Applicability for Plani Models i Cooling Analysis Calculations l

Letter Rpt.

WCAP 14776 NSD/NRC 97-5014 WCfr and OSU Data WC/T and OSU Data Comparisons of Comparisons of SB01,SB10 SB01 & SB10

@ 812 & SB23 1. 3000 Sec.

Windows l

r .-

WC/T Extended Time Calculation -

SB01 from 1260 sec. to 4600 sec.

- Upper Plenum Collapsed Liquid Level

- Downcomer Collapsed Liquid Level

- Core Collapsed Liquid Level DVl-1 Injection Flow -

Integrated DVI-1 Flow ADS 4-1 Flow l

Integrated ADS 4-1 Flow 1

1 i

t i

The Following Figures are in the Proprietary Version of this Report l l

Figure 23-23 i

V Figure 23-24 ,

Figure 23-22 Figure 23-3 Figure 23-8 Figure 23-17 Figure 23-18 i

N

- _ - _ _ _ _ - - _ _ - - - _ _ _ _ _ _ _ . - _ _ - - - - - - - - _ _ _ _ - _ _ - _ _ - - - - _. - - e - - e ,_-_- - _ _ _ _ _ . - - - - , - - - _ _ - - -- . _ - _ - - - - - _ - - - - - - _

se-TNC/T Extended Time Calculation -

l SB01 from 8000 sec. to 11000 sec.

l

- Upper Plenum Collapsed Liquid Level Downcomer Collapsed Liquid Level I

Core Collapsed Liquid Level .

DVI-1 InjecIion Flow Integrated DVI-1 Flow ADS 4-1 Flow Integrated ADS 4-1 Flow l

i The Following Figures are in the Proprietary Version of this Report Figure 2.4-23 Figure 2.4-24 Figure 2.4-22 Figure 2.4-3 Figure 2.4 8 Figure 2.4-17 Figure 2.4-18

--- . . _ _ _ _ _ _ _ - - - _ _ _ _ _ - _ _ _ . _ - _ . . - _ _ - - _ . - - _ _ _ _ _ _ _ _ _ _ - . - _ _ _ _ _ _ - _ _ - _ _ - _ - _ - _ _ _ - _ - - - - - - _ _ - - - - _ . - _ - - - _ _ _ _- a -e> n - ~-

6e i

1 1

l \

l WC/T Extended Time Calculation - j l

SB10 from 13,500 sec. to 16,500 sec.

l

- Upper Plenum Collapsed Liquid Level l

- Downcomer Collapsed Liquid Level

- Core Collapsed Liquid Level

- DVl-1 Vessel Inlet Temperature

( - DVI-2 Vessel Inlet Temperature

• 1 IRWST DVI-1 Injection Flow l

- IRWST DVI-2 Injection Flow Sump Injection 1 Flow l

Sump Injection 2 Flow

- Total DVl-1 Injection Flow Total Integrated DVl-1 Flow i

Total ADS 4-1 Flow Total Integrated ADS 4-1 Flow  !

l I

i I

t The Following Figures are in the Proprietary Version of this Report Figure 2.5-23 Figure 2.5-24 Figure 2.5-22 Figure 2.5-11 Figure 2.5-12 i

Figure 2.5-3 Figure 2.5-4 Figure 2.5-5 Figure 2.5-6 Figure 2.5-7 Figure 2.5-8  ;

Figure 2.5-19 Figure 2.5-20

____m - _ _

sC l

WC/T Code Validation for AP600 l Lona Term Coolina Analysis 1

I i

Letter Rpt.

WCAP-14776 NSD/NRC-97 5014

@ WC/T Pedormance in Window Mode Calculations WC/T Performance in Window Mode Calculations @

1. Initial Condition Sensitivity 1. ExtendedTime Sensitivity 1

2. Boundary Cond.

Sensitivity l

e [ WC/T O Summan/ -

WC/T LTC '

f Validation of WC/T Loop and Vessel 5 for A Applicability Models ' AP600 Long Term for Plant Cooling Analysis Calculations l

l l Letter Rpt.

. WCAP-14776 NSDiNRC-97 5014 l

WC/T and OSU Data WC/T and OSU Data Comparisons of Comparisons of I

@ SB01, SB10, SB01 & SB10 @

l B12 & SB23 1. 3000 Sec.

Windows 1

? I I

l t

$ d' Summary of WC/T vs. OSU Data

- Upper Plenum Level Comparison

- Downcomer Level Comparison

- Total Vessel Inflow (DVI) Comparison

- Total Vessel Outflow Comparison

- Vessel Pressure Comparison

l 1

t 1

l l Downcomer Liquid LeveI Comparison 1 (a,b,c)

~]

l

\

L. _ . _ _ . _ - - . . . _ _ _ _

Upper Plenum Liquid LeveI Comparison (a,b.c) r**"" _

O l

1 l

l j

l

I I

l l

l Comparison t

Reactor Vessel Total Inflow l

(a,b.c) ,

1 I

I l

1 4

1 1

l l

l l

i w

l

l l l

l Reactor Vessel Total OutfIow Comparison (a,b.c )

l l

1 1

I l

1 l

l i

l l

l 4

)

l l

l

ss 1

Vessel Pressure Data Comparison  !

l 1

- Measured vessel (upper head) pressure range is 15.5 psia to 16.0 psia with a pressure sensor uncertainity -of 2.44 psia at the 2a uncertainty level.

- Calculate pressure of all tests were in the range of 15.3 psia to 15.9 psia during IRWST draindown and sump operation.

- Calculated vessel pressures show.excellant comparison with the measure values, i.e. well within the uncertainity bands.

l

- - - . - .. . - - - _ _ . ._ _ - _ . . - _ _ _ _ _- . -- - - . _ . . . . ~ . ...

REACTOR VESSEL PRESSURES DURING IRWST DRAINING OSU Test sbO1, sb12, sb18, & sb23 (a,b,c) l l

i i

i 1

l 1

I

- l

$6 Conclusions from WC/T Code Validation for AP600 Application

1. Several extended WC/T calculations show no indications of solution I

divergence at 3000 seconds or approximately 5 to 10 times the period required to reach a quasi-equ!ibrium solution. .

I-

- Extended Time Sensitivity Solution

! - Boundary Condition Sensitivity Solution

- 3 Data Comparison Solutions .

2. WC/T underpredicts reactor vessel collapsed liquid levels slightly in OSU tests providing a degree of conservatism. ,

1

3. WC/T predicts total vessel inflows and outflows in the OSU tests within l the 2a uncertainity of the flow sensors.

1

4. WC/T predicts the reactor vessel pressures in the OSU tests within the l 2a uncertainity of the pressure sensors.

4

AP600 LONG TERM COOLING SSAR CALCULATIONS WITH WCOBRA/ TRAC i

LONG TERM COOLING OF AP600 IS UNIQUE j PASSIVE SAFETY-RELATED SYSTEMS l

QUASI-STEADY-STATE CONDITIONS i

ESTABLISH AND VERIFY A SIMPLIFIED WCOBRAfrRAC NODALIZATION  !

VESSEL CHANNELS USED FOR HOT LEGS, COLD LEGS  ;

VALIDATE AGAINST OSU LONG TERM TEST RESULTS CALCULATE AP600 PERFORMANCE AT LIMITING, DISCRETE TIMES i USING WINDOW MODES

/cm/451rek.wpf PageI

. - . .. . . . - - . _ . . . . . - . - - . ~ . . - - - - . . . . _ . . . ~. ..~. . ~ . - - . , _ . . . . . . . . - .

METHODOLOGY TO PERFORM A WINDOW MODE ECCS PERFORMANCE ANALYSIS

1. IDENTIFY LIMITING PORTION (S) OF THE LTC PHASE, THE MOST DEMANDING ON THE SAFETY SYSTEMS.

2. ESTABLISH BOUNDARY CONDITIONS FOR WCOBRA/IRAC.

3. SELECT REPRESENTATIVE INITIAL CONDITIONS FOR CALCULATION.

4. EXECUTE WCOBRA/ TRAC UNTIL QUASI-STEADY STATE ACHIEVED.

i t

/cm/451nntwpf Page 2

t SSAR LONG TERM COOLING ANALYSIS STRATEGY i i

ANALYZE IN COMPLIANCE WITH APPENDIX K APPLY CONSERVATISM IN GENERATING CONDITIONS FOR THE WINDOW CALCULATIONS: FOR START OF SUMP RECIRCULATION: ,

MAXIMIZE IRWST DRAIN RATE FOR MAXIMUM DECAY HEAT AT 4 SUMP INITIATION  ;

MAXIMIZE ENERGY OF LIQUID EXITING ADS-4 DURING IRWST INJECTION TO MAXIMIZE SUMP TEMPERATURE AND MINIMIZE CONTAINMENT PRESSURE ADDRESS THE SPECTRUM OF LOCA BREAK SIZES

?

f

/can/451nnLwpf Page 3

WGOTHIC COMPUTES CONTAINMENT CONDITIONS THROUGHOUT THE TRANSIENT i

LOW PRESSURE STIPULATED BY APPENDIX K CONSERVATIVE ASSUMPTIONS APPLIED MASS / ENERGY RELEASES GUTTERS PRESUMED INOPERATIVE MAXIMUM PCS WATER FLOW EXTERNAL TO CONTAINMENT MINIMUM PCS WATER TEMPERATURE 1.05* BEST ESTIMATE FREE VOLUME NO HEAT TRANSFER MODELING PENALTIES MINIMIZE INITIAL AIR MASS PRESENT MAXIMIZE EXTERNAL SURFACE WETTING

l Figure 4.2 Small Break LOCA LTC Calculation Containment Input t

l l

I f I I

NOTRUMP Short Mass & Energy EGOTHIC (Time O Zero to Start of Term Analysis Data IRWST Drain)

If i

Appendix K Core Boiloff During Containment m _

Decay Heat IRWST Drain Pressure for IRWST Dram n

V If h Mass & IRWST Drain Rate Energy Data Calculation IRWST Draining I f Sump Injection 1. Containment Pressure WGOTHIC (Time

> 2. Sump Levels p

Zero into Sump 3. Sump Temperatures

• Injection)

If Select Window Mode Times and Boundary Conditions Case 1 Case 2 Case 3 o o n

, WC/T WC/T WC/T l

LTC LTC LTC Calc Calc Calc j u o o Chapter 15.6 SSAR (RCS & Core Conditions) c \f1w\ work \ltecale pre 030497 sen

INITIAL CONDITIONS FOR WINDOW CALCULATION t INITIAL CONDITIONS ARE ESTIMATED AND DO NOT DETERMINE THE QUASI-STEADY STATE OBTAINED PRIMARY CIRCUIT LIQUID LEVELS AND TEMPERATURE  ;

STEAM GENERATOR SECONDARY SIDE LIQUID LEVELS AND TEMPERATURE STRUCTURE TEMPERATURES i

WINDOW APPROACH HAS SHOWN THAT AN EQUIVALENT QUASI-STEADY STATE WILL BE REACHED FROM ANY REASONABLE VALUES FOR THESE INITIAL CONDITIONS, AS VALIDATED BY OSU  !

SIMULATIONS ANALYZE AP600 CASES USING INITIAL CONDITIONS ESTIMATED FROM EARLIER CALCULATIONS l

i  !

I

/m/451rmk.mTf Page 6

. . . . _ _ = . . - - . . . . . - . . . . - _ . . . . . - _ _ . - _ . _ _ . - . . . . _ . . . . . . . - . . - +. . -.

BOUNDARY CONDITIONS FOR WINDOW CALCULATION BOUNDARY CONDITIONS WHICH DETERMINE THE QUASI-STEADY STATE CORE POWER (APPENDIX K DECAY HEAT)

IRWST LIQUID LEVEL AND TEMPERATURE CONTAINMENT PRESSURE SUMP LIQUID LEVEL AND TEMPERATURE 1

I t

I i

/cin/451rrnLup Page 7 i

CRITERIA FOR ACHIEVING A QUASI-STEADY STATE KEY VARIABLE REMAINS STEADY OVER AN EXTENDED PERIOD CORE LIQUID LEVEL DOWNCOMER LIQUID LEVEL UPPER PLENUM LIQUID LEVEL UPPER PLENUM PRESSURE DVI INJECTION RATE -

ADS STAGE 4 FLOW t

Ann /Cimk.y p,,, g

AP600 LONG-TERM COOLING CASES FOR FINAL SSAR '

CONSERVATIVE ANALYSIS BASES UTILIZED CONTAINMENT CONDITIONS .

SINGLE FAILURE OF ONE PASSIVE SAFETY SYSTEM COMPONENT APPENDIX K DECAY HEAT MAXIMUM DESIGN FLOW RESISTANCES FOR INJECTION PATHS ,

AND ADS PATHS MODELING PER THE WC/T OSU FINAL VALIDATION REPORT CASES TO SHOW ADEQUATE CORE COOLING IN THE LONG TERM i

r

. [

wei, i. rt r,

AP600 SSAR LONG-TERM COOLING WINDOW MODE CASES SET 1 - DOUBLE-ENDED DVI LINE BREAKS CASE I - DESIGN BASIS: ONLY PASSIVE SYSTEMS OPERATE WINDOW INCLUDES THE LATE IRWST INJECTION PHASE ON INTO REPRESENTS EARLIEST SWITCHOVER TO SUMP INJECTION AND, THEREFORE, THE HIGHEST DECAY POWER FOR SUMP INJECTION l

CASE II - SYSTEMS INTERACTION: RNS OPERATION INITIALLY RNS FAILURE ASSUMED AT THE TIME OF SUMP SWITCHOVER, AFTER  ;

IRWST HAS BEEN DISCHARGED RAPIDLY BY PUMPS IN THIS WINDOW, SUMP INJECTION BEGINS EVEN EARLIER THAN IT ,

DOES IN CASE I .

CASE III - WALL-TO-WALL FLOOD UP IN THE VERY LONG-TERM i WINDOW MODELS THE LEVEL REACHED WHEN ALL COMPARTMENTS ,

BELOW LIQUID SURFACE HAVE FILLED DUE TO PASSIVE LEAKAGE MINIMUM SUMP LEVEL FOR DESIGN BASIS EVENTS

/cm/45 trmk-# Page 10 .

i AP600 SSAR LONG-TERM COOLING WINDOW MODE CASES (CONT'D) l SET 2 - SMALL COLD LEG BREAKS l

CASE I - TWO-INCH COLD LEG BREAK WITH ONE ADS-4-PATH FAILED WINDOW INCLUDES THE LATE IRWST INJECTION PHASE ON INTO STABLE SUMP INJECTION REPRESENTATIVE OF SMALL BREAK LOCA SWITCHOVER TO INJECT FROM A NEAR-SATURATED SUMP i CASE II - TWO-INCH COLD LEG BREAK WITH ONE DVI PATH FAILED SINGLE FAILURE SENSITIVITY CASE i

i

/ani45:not rr r. in

h AP600 SSAR LONG-TERM COOLING WINDOW MODEL CASES (CONT'D) i SET 3 - LARGE COLD LEG (DECLG) BREAK CASE I - CONTINUE SHORT-TERM TRANSIENT BEYOND ADS 1-3 INJECTION LEVEL SHOWS CONTINUED COOLING AFTER ACCUMULATORS ARE EMPTY BY CMT INJECTION '

LESS AVAILABLE HEAD THAN EXISTS ONCE THE IRWST BECOMES  :

AVAILABLE 1

CASE II - WINDOW CONSIDERS IRWST INJECTION AT THE TIME AT WHICH  !

THE SUMP LEVEL HAS RISEN TO WITHIN THE PERIMETER OF THE BROKEN COLD LEG t FAIL ONE ADS-4 FLOW PATH i CASE III - WINDOW CONSIDERS INJECTION FROM AN IRWST REFILLED WITH CONDENSATE RETURN FROM THE CONTAINMENT GUTTERS ,

SENSITIVITY TO GUTmR OPERATION (RAI RESPONSE)

/cm/451nnLwpf Page 12

CONCLUSIONS:

THE WCOBRA/ TRAC WINDOW MODE ANALYSIS METHODOLOGY IS A VALID TECHNIQUE TO CALCULATE ECCS PERFORMANCE OF AP600 DURING LONG-TERM COOLING INPUT IS GENERATED SO AS TO OBTAIN A CONSERVATIVE ANALYSIS RESULT WINDOWS SELECTED FOR THE SSAR LOCA ANALYSIS INVESTIGATE BOUNDING SCENARIOS l

t i

l

/cm/451nnk_wpf Page 13

Simplified AP600 Internri Containment Flow Network t

5

.cr e ct:~c

.m

.\ / .

i s: i --]

Omf CMT f

=wsr i i

v

_.J L_ _J .

.C; *C s

.CC'M - i i

CVCS i

__ t.rca .

G- ..

n .-.-. w ., .

. n

.. .- . . . ,.. . . . s

. c. aw .

,. 1, ..,

(Not to Scale) _

DRAFT AGENDA Friday, March 28,1937 LONG TERM COOLING ACRS MEETING

1. Introduction

a. Computer Code Selection a

b. Window Mode Approach Definition

2. PIRT

3. WC/T Validation

a. OSU Model

b. Sensitivity Calculations

c. Comparisons with Data

4. AP600 Plant Model

a. Plant Model ,

b. Containment Boundary Conditions

5. Conclusions I

i l

i March 1J. 1991 I NRCsLTC 10 397