Letter Sequence Other |
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Results
Other: ML17268A104, ML19347F660, ML20003B230, ML20010G846, ML20010G862, ML20032A736, ML20063F261, ML20065N032, ML20067D230, ML20079Q273, ML20079Q282, ML20133E265
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MONTHYEARML19257A5131979-12-28028 December 1979
Forwards Addl Response to ,Per Joint Nrc/B&W Owners Group 790913 Meeting.Addresses Noncondensible Gas Discussion & Small Break & Power Operated Relief Valve stuck-open Discussion
Project stage: Meeting
ML20003B2301981-01-30030 January 1981
Informs That Certain Mods Will Be Made to Existing Small Break LOCA Model,In Response to NRC .Revised Model Documentation Will Be Provided by 820301
Project stage: Other
ML20003B6721981-02-16016 February 1981
Submits Addl Comments on NUREG-0737,Items II.B.2 & II.K.3.30.Design Review Completed Re Plant Shielding for Spaces Outside Containment That May Be Used in post-accident Operations
Project stage: Request
ML19347F6601981-05-19019 May 1981
Responds to RW Reid Re Small Break LOCA Model to Predict Small Break Behavior.Discusses L3-1 & S-07-10D Test Prediction Comparisons.Earlier Pretest Predictions Being Reviewed & Results to Be Submitted by 810615
Project stage: Other
ML17268A1041981-05-31031 May 1981
B&W Post-Test Evaluation of Loft Test L3-1
Project stage: Other
ML20010G8621981-06-0909 June 1981
B&W Post-Test Analysis for Semiscale Test S-07-10D
Project stage: Other
ML20010G8461981-09-15015 September 1981
Forwards B&W Post-Test Analysis for Semiscale Test S-07-10D & B&W Post-Test Evaluation of Loft Test L3-1, in Response to NRC Re Small Break LOCA Model to Predict Small Break Behavior
Project stage: Other
ML20032A7361981-10-23023 October 1981
Requests That Buchholz to Eisenhut Be Added to Facility Dockets as Final Response to NUREG-0737,Item II.K.3.30 Re Small Break LOCA
Project stage: Other
ML20052A0611982-03-25025 March 1982
Summarizes NRC Views Resulting from 811217 Meeting W/B&W Owners Group Re Small Break LOCA Analysis Model & Provides Addl Info for Planning Verification Program. Model Verification Endorsed
Project stage: Meeting
ML20062M1431982-08-13013 August 1982
Responds to Requesting Schedule for Submittal of Supplemental ECCS Calculations Using Cladding Models of NUREG-0630.Calculations Will Be Submitted by 830301
Project stage: Supplement
ML20063F2611982-08-25025 August 1982
Discusses Program for Resolution of NUREG-0737,Item II.K.3.30, Revised Small Break LOCA Methods to Show Compliance w/10CFR50,App K. B&W Will Forward Description of Gerda Test Program
Project stage: Other
ML20065A8891982-09-0909 September 1982
Submits Details of Cooperative Evaluation Program,Requested at 820720 Meeting Re NUREG-0737,Item II.K.3.30, Revised Small Break LOCA Methods to Show Compliance w/10CFR50,App K. Program Will Lead to Development of Research Priorities
Project stage: Meeting
ML20065N0321982-10-19019 October 1982
Responds to Requesting Implementation Schedule for Mods to ECCS Evaluation Models.Mods Will Be Undertaken as Extension of NUREG-0737,Item II.K.3.31.Schedule Will Be Provided 60 Days After NRC Approval of Item II.K.3.30
Project stage: Other
ML20067D2301982-12-0707 December 1982
Endorses B&W Topical Repts BAW-10154P, B&W Small Break LOCA ECCS Evaluation Model & BAW-10092P,Revision 3, CRAFT-2, in Effort to Complete Small Break LOCA Methods Program Response to NUREG-0737,Item II.K.3.30
Project stage: Other
ML20023B8711983-04-0505 April 1983
Public Version of Temporary Mod Request T-7104 to Emergency Plan Implementing Procedure Ei 1300.07, Technical Support Ctr Activation. Rev 27 to Index Encl
Project stage: Request
ML20079Q2821983-05-0606 May 1983
Bounding Analytical Assessment of NUREG-0630 on LOCA & Operating Kw/Ft Limits
Project stage: Other
ML20079Q2731983-05-0606 May 1983
Forwards Bounding Analytical Assessment of NUREG-0630 on LOCA & Operating Kw/Ft Limits, Per
Project stage: Other
ML20133E2651985-07-0303 July 1985
Topical Rept Evaluation of BAW-10092P,Rev 3 & BAW-10154 Re Small Break LOCA Evaluation Model CRAFT2 (Rev 3).CRAFT2 in Compliance W/Evaluation Criteria of 10CFR50,App K
Project stage: Other
1982-10-19
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TOLEDO Tamm EDISON Ac cP CRoust Docket No. 50-346 0.7 License No. NPF-3 e.
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Serial No. 709 d
May 19, 1981 Director of Nuclear Reactor Regulation Attention:
Mr. John F. Stolz 5
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Operating Reactor Branch No. 4 Division of Operating Reactors United States Nuclear Regulatory Commission Washington, D.C.
20555
Dear Mr. Stolz:
This letter is in reference to Mr. R. W. Reid's letter dated February 24, 1981 (Log No. 663) to all Babcock & Wilcox Licensees concerning small break LOCA model to predict small bt.ak behavior. The following is Toledo Edison's response to this letter as it relates to Davis-Besse Nuclear Power Station Unit 1.
The B&W prediction of the L3-1 test compared very favorably with the other vendor predictions. All of the predictions showed the clearing of liquid from the pump loop seal. However, the test did not produce this result due to a bypass flow path which existed between the vessel upper head and the downcomer annulus, as well as another bypass between the hot and cold leg pipes due to leakage through the reflood assist valves.
EG6G calculations indicate that this leakage path in LOFT is approximately 3 percent of the core flow, or comparable to prototype valves. However, the actual leakage path ce m.
be measured directly but only indirectly inferred by assuming a valca -.2ch leads to the prediction agreement with the test. Therefore, the leakage flow from L3-1 must be further evaluated before additional analytical work could be justified. In addition, on page 40 of EGG-CAAP-5255 (LOFT L3-1 Preliminary Comparison Report) it is stated that B&W was the anly vendor who accurately calculated the behavior of the secondary side cf the steam generator. For these reasons, we are of the opinion that only a marginal benefit at best could be realized from further evaluation of the L3-1 test.
Regarding the S-07-10D test, the situation is a little different. None of the vendor predictions characterized the test very wel.1.
However, we feel this is due in large ceasure to insufficient information to model
[
the steam side of the steam generator, as well as insufficient dara on
/I N the valve and assceiated piping. There is also insufficient infomation 3
to adequately model the steam separator. Based on these reasons, we are of the opinion that our current results are not unreasonable considering 0
the conservative features of the model B&W used to predict the experiment.
THE TOLEDO EDISON COMPAN
EDISON PLAZA 300 MADISON AVENUE TOLEDO, OHIO 43652 81052203W/
[
t Docket No. 50-346 License No. NPF-3 Serial No. 709 May 19, 1981 Toledo Edison is reviewing the earlier pre-test predictions in light of the identified test uncertanties and model conservatisms to confirm the validity of the existing evaluation model.
The analysis of the L3-6 test, which was completed and submitted to Dr.
Sheron on March 23 required an extensive manpower commitment. Due to this and the continuing effort to respond to the requirements of NUREG-0737 and others, Toledo Edison will provide any pertinent information resulting from the above mentioned review by June 15, 1981.
Very truly yours, O
RPC/ CAB: lab 1
cc: DB-1 NRC Resident Inspector l
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