ML17321A499

Discusses 850315 Telcon Re Incorrect Expression for Multiplier on Heat Transfer Coefficient Used in TOODEE2, Which Affected LOCA-ECCS Analyses for Several Pwrs.Analyses Redone

ML17321A499
Person / Time
Site:	Cook
Issue date:	03/21/1985
From:	Owsley G SIEMENS POWER CORP. (FORMERLY SIEMENS NUCLEAR POWER
To:	Harold Denton Office of Nuclear Reactor Regulation
References
GFO:85:008, GFO:85:8, NUDOCS 8503270251
Download: ML17321A499 (4)

Text

REGULATOR NFORMAT'ION DISTRIBUTION S l'EM f RIDS)

ACCESSIQN NSR;8503270251 DOC. DATE: 85/03/21 NOTARIZED: NO DOCKET y FACIL:50 BYNAME315 Donald C, Cook. Nuclear Power Plant~ Unit 1< Indiana 8 05000315 AUTH AUTHOR AFFILIATION OWSLEYFG ~ F ~ Exxon Nuclear Co,g Inc ~,(subs, of Exxon Corp,)

RECIP ~ NAME RECIPIENT AFFILIATION DENTONtH ~ Office of Nuclear Reactor" Regulationi Director SUBJEGT: Discusses 850315 telcon Tre incorpect expnession for" multiplier on heat transfers coefficient used in TOODEE2f, which affected LOCA ECCS analyses for several PNRs,Analyses'edone DISTRIBUTION:CODE: A001D TITLE: OR COPIES RECElyED:LTR Submittal: General Distribution

..ENCl. o SIZE>.'.,

NOTES; 05000315 OL: 10/25/74 RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL" ID CODE/NAME LTTR NRR ORB1 BC 01 ENCL'NTERNAL:

ACRS 09 ADM/LFMB, 1 ELD/HDS3 1- NRR/DE/MTEB 1 NRR/DL DIR 1 1 NRR/DL/ORAB 1 NRR/DL/TSRG 1 NRR METB 1 NRR/DS I/RAB 1 1 G FI 00 1 RGN3 1 1 EXTERNAL: LPDR 03>> NRC PDR NSIC 05~

02'ing.

p, +~rag.

TOTAL NUMSER OF COPIES REQUIRED: LTTR + ENCL I3i3

1f,Jfg<hr,,

~ >I

~ ( l n K r

JK 1

Kl 0

h PI

EQQM NUCLEAR COMPANY, INC.

600 108TH AVENUE NE, PO BOX 90777, BELLEVUE,WA 98009 (206) 453-4300 March 21, 1985 GFO:85:008 Mr. Harold Denton, Director Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D.C. 20555

SUBJECT:

Error in the 48,000 MWD/MTU LOCA-ECCS Analysis for D.C. Cook Unit 1 Ref.: XN-NF-83-61, "D.C. Cook Unit 1 LOCA-ECCS Analysis for Extended Exposure," August 1983

Dear Mr. Denton:

, As discussed in a telephone conversation on March 15, 1985 with Mr. David Moran, Mr . Norm Lauben and Mr. Robert Jones of your staff, an error was discovered which affected the LOCA-ECCS analyses for several PWRs. The error was in an expression for a multiplier on the heat transfer coefficient used in TOODEE2, which was incorrectly programmed into the code.

TOODEE2 calculates the thermal response (heatup) of the hot fuel rod following the end of the blowdown transient until the core temperature transient is terminated. The incorrect coding caused the heat transfer coefficient multiplier in TOODEE2 to be 1.045, when it was intended to be 1.0 based on input to the code.

One such analysis affected by this err or was the analysis to support increased burnup from 42.2 MWD/kg to 48.0 MWD/kg in D.C. Cook Unit 1. The analyses to support burnup points up to 42.2 MWD/kg were previously reported in XN-NF-81-07 and were done with a version of TOODEE2 which did not contain the error. ENC has redone the analyses reported in XN-NF-83-61 to support the increased burnup to 48.0 MWD/kg.

The peak clad temperature is calculated with the corrected version of TOODEE2 at 48 MWD/kg to be 1785oF versus the previous value of 1736oF. The reanalysis verifies that the plant satisfies the 2200oF limit of 10 CFR 50.46.

If there are questions, or if I can be of further help, please contact me.

Sincerel G. . Owsley, anager Reload Licen ng Liaison gf CC: Mr,. - J. G.

Mr. D. L.

Feinstein;,

Wigginton (AEP ) e~ A~: @ej2 l

j

~I (USNRC) II9 ygygeL~

850327025i 85032i i aw~UATEoFExxoMcoRPoRATloN PDR ADOCK 050003i5 PDR

r i

h L

J