And now, on April 7, 2007, I observe, indeed it is interesting to note that the ACRS handled the chaotic TRACE situation by hiding its evaluations of the mammoth smokescreen. Indeed, the ACRS produced its report, TRACE Thermal-Hydraulic Analysis Code. However, the report is not available to the public, and there is no transcript of the ACRS proceedings that produced that report. And that is what I mean by Hiding a mammoth SMOKESCREEN!
Following is the very sketchy ACRS letter report in italics (ML070810911) and the reference, the Eltawila memorandum, is not available to the public.
ACRSR-2242
March 22, 2007
The Honorable Dale E. KleinChairman
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001
SUBJECT: DEVELOPMENT OF THE TRACE THERMAL-HYDRAULIC SYSTEM ANALYSISCODE
Dear Chairman Klein:
During the 540th meeting of the Advisory Committee on Reactor Safeguards (ACRS), March 8-9, 2007, we completed our report on the development of the TRACE thermal-hydraulic (T/H) system analysis code. We also discussed this matter during our 539th meeting, February 1-3, 2007. Our Thermal-Hydraulic Phenomena Subcommittee discussed this matter on December 5, 2006. During these reviews, we had the benefit of discussions with representatives of the NRC staff and its contractors. We also had the benefit of the document referenced.
RECOMMENDATIONS
1. The schedule for documenting, validating, and peer reviewing TRACE should beaccelerated and the work completed expeditiously.
2. The development of a representative set of TRACE plant models and user testing onapplications should also be accelerated to facilitate timely incorporation of TRACE intothe regulatory process.
BACKGROUND AND DISCUSSION
In the mid-1990s, the Office of Nuclear Regulatory Research, working with the Office of Nuclear Reactor Regulation, determined that the four primary reactor system T/H codes that were in use at that time should be consolidated into one code. These codes included RELAP5 (LOCA), TRAC-P(PWR-LOCA), TRAC-B(BWR LOCA), and RAMONA (BWR Stability).
The models, correlations, and solution methodologies in these codes did not reflect the state-of-the- art and required in-depth review and modification. It was also recognized that they had been designed at a time when computer capabilities were limited and included many structural aspects, such as memory management, that were no longer needed and increased the cost of code maintenance and development. The availability of graphical user interfaces and their wide acceptance also suggested the desirability of incorporating similar capability in NRC codes. All these considerations led to extensive code consolidation, model improvements, and implementation efforts culminating in the development of TRACE .
TRACE is intended to serve as the main tool for confirmatory analyses of a broad range of thermal-hydraulic problems for current and future reactor designs. It has the potential to offer significantly enhanced capabilities for state-of-the-art analyses of thermal-hydraulic issues. Applications include certification of new reactor designs and the regulatory review of power uprates for currently operating reactors. Therefore, the schedule for documenting, validating, and peer reviewing TRACE, as well as the development of plant input decks, should be accelerated. The work should be completed expeditiously to enable the incorporation of the code into the regulatory process.
Sincerely,
/RA/
William J. Shack Chairman
Reference:
1. Memorandum from Farouk Eltawila, Director, Division of Risk Assessment and SpecialProjects, Office of Nuclear Regulatory Research, to Frank Gillespie, Executive Director,ACRS, “TRACE V5.0 Documentation and Support”, January 31, 2007
Note: The following paragraphs are extracted from my other blog, http://nuclearenergyblog.blogspot.com/
It is not a TRACE; it is a mammoth SMOKESCREEN
Wednesday, February 28, 2007
Somewhat periodically the NRC's ACRS reviews activities in the production of the massive so-called thermal hydraulics code, TRACE. The most recent review by the ACRS Thermal-Hydraulics Phenomenon Subcommittee , December 5, 2006, page 9, includes the following remark by MEMBER WALLIS: We recommended in our research report that TRACE becomes the tool for the agency. We recommend TRACE should actually become the mature code used by the agency all over the place and we wanted to see it mature and you say it's going to be universal documentation in 2007, but was sent to us to review seemed to be a hodgepodge of all kinds of stuff. What I want to review is a draft final document, not a hodgepodge of stuff which I have to figure out - not even dated. I don't even know whether some of the documents are old or new or what they are. That's not very helpful to us.
The entire transcript may be viewed at:
http://www.nrc.gov/reading-rm/doc-collections/acrs/tr/subcommittee/2006/th120506.pdf
Going back to January 11, 2001, The ACRS issued a letter, Issues Associated With Industry-Developed Thermal-Hydraulics Codes. It is a lengthy tome with a very lengthy appendix.
http://www.nrc.gov/reading-rm/doc-collections/acrs/letters/2001/4781926.html
The appendix includes the following section; I am quoting only the heading and the last sentence:
4. Codes have evolved, but the development process is hard to trace.This situation supports the need for the staff to have its own code and to maintain a clear record of why design choices were made in its development.
Now, the TRACE racket has been proceeding under various guises for decades.
Fortunes have been cast to the winds, not only in the software extravaganzas, but in the vast array of American as well as international test programs. The connections and relevance of the test programs to TRACE are obscure at best. The most recent disclosure of a link between testing and TRACE is from Staudenmeier in his slide presentation to the ACRS Thermal-Hydraulics Phenomenon Subcommittee on February 15, 2005. He discussed four test series; FLECHT, CCTF, SCTF, THTF, but these are a very small sample of the vast test programs that have been conducted, largely on the basis that they were needed for code development and proof testing. There is no mention of extensive LOFT and SPERT projects that were conducted decades ago at the presently named Idaho National Laboratory. This 2005 transcript may be viewed at:
http://www.nrc.gov/reading-rm/doc-collections/acrs/tr/subcommittee/2005/th021505.pdf
There is no mention of the "... more than 50 tests ..." that are discussed in my entry of February 20, 2007. Returning to that matter, here are some extractions from the NRC Memo that predates the Staudenmaier slide show by almost one year.
Memo to Matthews/Black-Technical Safety Analysis of PRM-50-76,
A Petition for Rulemaking to Amend Appendix K to 10 CFR Part 50 and Regulatory Guide 1.157
ML041210109. 18 pagesApril 29, 2004
Mr. Leyse states that:“Petitioner is aware that more experiments with Zircaloy cladding have not been conducted on the scale necessary to . . . overcome the impression left from run 9573.”
In the above Memo, the NRC responded to its quote of Leyse as follows:
In the early 1980's, the NRC through Pacific Northwest Laboratories (PNL) contracted with National Research Universal (NRU) at Chalk River, Ontario, Canada to run a series of LOCA tests in the NRU reactor. More than 50 tests were conducted to evaluate the thermal-hydraulic and mechanical deformation behavior of a full length 32-rod nuclear bundle during the heatup, reflood and quench phases of a large break LOCA. Two tests were initially selected (References 17 and 18) for COBRA/TRAC (Reference 19) simulation to assess the applicability of that code. The NRC is reviewing the data from this program to determine the value of using it to assess the current generation of codes such as TRAC-M (Reference 20), now renamed TRACE.
The full ACRS meets March 8, 9 and 10, 2007 and will include the preparation of several ACRS reports in open sessions. One of the reports is "TRACE Thermal-Hydraulic Analysis Code." It will be interesting to find out what ACRS thinks about this chaotic situation.
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