ML20154H440
| ML20154H440 | |
| Person / Time | |
|---|---|
| Issue date: | 01/03/1986 |
| From: | Sullivan H NRC, Advisory Committee on Reactor Safeguards |
| To: | Boehnert P Advisory Committee on Reactor Safeguards |
| References | |
| ACRS-CT-1827, NUDOCS 8603100287 | |
| Download: ML20154H440 (3) | |
Text
O./U M WR b3DM b s
January 3, 1986
..,... a C.
s Mr. Paul A. Boehnert Advisory Committee on Reactor Saf eguards, H-1016 US Nuclear Regulatory Commission Washington, DC 20555
Dear Paul:
SUBJECT:
NOVEMBER 22, 1985, ECCS SUBCOMMITTEE MEETING COMMENTS This report is divided into four major areas to separate the comments on Budget, Integral Facilities, Separate Effects, and Codes.
Thermal Hydraulic Decision Unit Budget Dr. Shotkin presented the FY 1986, FY 1987, and FY 1988 thermal-hydraulics decision unit budgets. The budget is basically divided into three parts for FY 1987, Integral Facilities ($14.3M),
Separate Effects ($3.3M), and Transient Models and Codes (35.8M).
It is recognized that integral test facilities are expensive to build and operate, but I believe that the decision unit should be increased to provide additional funds for separate effects and transient models and codes (under the current budget climate this is not likely). I suggest that integral f acilities funding be reviewed in an effort to provide additional funding for both separate effects and transient models and codes. The reason for making this suggestion is that the thermal hydraulic codes have reached a reasonable state of maturity and further improvement will be made only through obtaining detailed information about specific phenomena using separate effect experiments. These future improvements are mainly in the area of constitutive equations that require detailed information in two-phase flow. This information is difficult if not impossible to obtain f rom integral experiments.
Separate effect experimental facilities presently exist, such as the INEL flow phase loop, which could provide some of this information.
Therefore, it is recommended that review of the codes constitutive equation packages be performed, areas of improvements be identified, separate-effect experiments be performed where required, and analytical models be developed for the codes. In addition, code assessment in the United States should be increased because we need a good understanding of our code's ability to calculate transients in power plants. I believe that we are currently relying too heavily on foreign code assessment and need to perform a larger portion in the United Staces.
8603100287 860103 PDR ACRS PDR CT-1827 I :1C 'TED C3!aDaL Cern % ) g g
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P. A. Boehn3rt Janunty 3, 1986 Prga 2 The thermal hydraulic division unit has had the same three basic I
subelements for'approximately the last five years. The budget. reviewers must' understand the fine details of each program to see the progress made in resolving is sues. As an example, Semiscale has performed tests to support the resolution of several significant safety issues in FY 1985, but the detailt; of the Semiscale test matrix must be known to determine i
this. Therefore, it is suggested that the subelements and possibly the decision unit be changed so that the safety issues being addressed are clearly visib.'e.
The advantage would be to show what issues are being resolved and :he progress made toward resolution.
Dr. Shotkin also addressed the establishment of a Technical.Intecration Center with a thermal-hydraulic center as the lead.
I believe that this will be an inportant development in FY 1986 and the ECCS Subcommittee should understand the Center's scope and function. It is import ant that NRR be able to use the Technical Integration Center to resolve licensing issues in the thermal-hydraulic area because they are one of tre real i
users of the research information and knowledge.
In FY 1987, the Continuing Experimental Capability (CEC) budget increases; in FY 1988 and FY 1989, it is a significant part of the integral f a cilities budget. If for some reason the CEC is not built, the Office of 1:esearch should develop a contingency plan that would keep an j
integral t est f acility (i.e., like Semiscale) operational to provide transient lata for code assessment.
I Integral Facilities I
The MIST f acility appears to be well on the way to operatio3 and production of test data. The MIST facility test matrix covers a wide range of transients for which data are needed of the B&W geometry.
Because the test will be performed over a short time, it in suggested that the E CS subcommittee have several meetings during the testing period to review the test results and understand the phenomena. In addition, it is suggested that more of these tests be used to assess the i.
code capability. Currently, 41 tests are planned and only 11 will be pretest calculations using RELAP5, TRAC, or RETRAN.
Separate Effects The entry of experimental data into the INEL experimental data bank is strongly supported and encouraged. It is very important that the data produced by experiments be placed in a data bank so it can be saved for later use. This is particularly important as the budget declines and facilities are closed.
I believe this effort should receive increased funding in FY 1987 and the later years.
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P. A. Boehne rt J nunry 3, 1986 Pigs 3 I also support the study of water hammers as they. affect nuclear plants.
A study should be conducted to identify the transient and condition that could cause water hammers, examine them to determine potential problem areas, and determine what information will be necessary to more complete understanding and resolution.
Transient Models and Codes I fully support the development of codes (both PWR and BWR) that keep the United States in the forefront of the international thermal-hydraulic code efforts.
This effort is relatively inexpensive when compared to integral facility testing and has provided an excellent tool for trading to the international community for needed experimental data. How long will the United States be able to maintain this lead at the current level of funding? Probably for only a year or two.
The International Code Assessment Program (ICAP) has been initiated by the Office of Research.
I support the NRR's comments that the program may be more extensive than necessary for providing verified codes and that more of the verification should be performed in the United States.
This is particularly true if a cadre.of staff is to be maintained in the United States to support the NRR staff for a rapid-response capability.
In general, the Office of Research presentation was well organized and provided key information and insights into how the budgets were obtained.
Sincerely yours, 2.w N Harold Sullivan Program Manager for Terrestrial Reactors HS:ke r
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