ML20083G631
| ML20083G631 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 12/30/1983 |
| From: | Hukill H GENERAL PUBLIC UTILITIES CORP. |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| References | |
| 5211-83-375, GL-81-21, NUDOCS 8401060333 | |
| Download: ML20083G631 (1) | |
Text
GPU Nuclear Corporation Q
Mf Post Office Box 480 Route 441 South Middletown, Pennsylvania 17057 0191 717 944 7621 TELEX 84 2386 Writer's Direct Dial Nurnber:
December 30, 1983 5211-83-375 Office of Nuclear Reactor Regulation Atta:
J. I'.
0:01., C;.icf Operating Reactors Branch No. 4 Division of Licensing U. S. Nuclear Regulatory Commission Washington, D.C.
20555
Dear Sir:
Three Mile Island Nuclear Station, Unit 1 (TMI-1)
Operating License No. DPR-50 Docket No. 50-289 Natural Circulation Cooldown (GL 81-21)
In our letter dated September 26, 1983 GPU Nuclear committed to a December, 1983 submittal of a natural circulation cooldown analysis using the RETRAN computer code.
Reference was made'to a detailed heat conductor nodalization of the upper head for use in RETRAN. Our investigations since then have shown that a better natural circulation cooldown calculation can be accom-plished using a multi-dimensional heat conduction code.
GPU Nuclear has embarked on such an analysis using the HEATING-5 code. HEATING-5 provides the multi-dimensional capability to model the vessel more accurately and possesses flexibility in the choice of boundary condition representation.
A 46 region HEATING-5 model has been developed which represents the reactor vessel head in two dimensions. The use of three dimensions was judged not to be necessary.
This approach is being utilized because it provides a more realistic representation of the heat transfer processes in this region of the reactor vessel. The additional time required to put the more complex HEATING-5 model together necessitates a submittal date beyond December, 1983. To date, the model has been formulated and is in the process of being initialized.
In order to verify the input, perform the long transient runs and review and document the results, it will necessitate our submitting the analysis to the h
NRC by March 20,1984.
8401060333 831230 Sincerely, PDR ADOCK 05000 P
. D. I kill Director, TMI-l O
HDH:LWH:vj f
(
cc:
R. Conte
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J. Van Vliet GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation I