IAEA1272 THACT-RR.

1. NAME OR DESIGNATION OF PROGRAM:  THACT-RR.

3. DESCRIPTION OF PROGRAM OR FUNCTION

A Computer Program for Analyzing Thermal-Hydraulics transients in Research Reactors. THACT-RR is a channel code. It analyses the transient response of a
research reactor core after power excursions or coolant flow and/or  coolant temperature changes. The THACT-RR code provides a
homogeneous one-dimensional compressible fluid flow capability with  an optional voiding model that estimates the void produced by sub-cooled boiling. It allows flow reversal and sub-cooled nucleate  boiling. It also includes a selection of flow instability, departure from nucleate boiling, single and two-phase heat transfer correlations, and a physical properties library adapted to pressures, temperatures, and flow rates encountered in research reactors.

4. METHOD OF SOLUTION

The conservation laws are solved by the method  of Characteristics coupled with an implicit finite difference technique to insure stability and convergence of the numerical scheme. The conduction equation is solved by an implicit finite difference method.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM:  The code is not adapted to very fast transient problems.

6. TYPICAL RUNNING TIME

Less than 5 min CPU are necessary for the sample problem related to a IAEA Benchmark fast loss of flow transient with a constant time step of 10**-3 Sec.

7. UNUSUAL FEATURES OF THE PROGRAM

The THACT-RR thermal-hydraulics model is based on steady state correlations. Their use is not always justified, but in quasi-steady state cases, such as loss-of-flow transients, this seems to be quite useful.

8. RELATED AND AUXILIARY PROGRAMS:  No additional programs are required.

10. REFERENCES

- B. Baggoura and A. Bousbia Salah:
  THACT-RR - A Computer Code for Analyzing Thermal-Hydraulics
  Transients in a Research Reactor Core
  Internal Report, C.D.S.E. (1992) to be published.
- C. Obenchain:
  PARET - A Program for the Analysis of Reactor Transients
  AEC Research and Development Reports
  IDO-17282 Phillips Petroleum Company (January 1969).
- R.P. Morgan:
  A Review and Discussion of Literature Concerning Transient Heat
  Transfer and Steam Formation
  IDO-17226 (1967).
- A.E. Bergles, J.C. Collier, J.M. Delhaye, G.F. Hewitt, F.
  Mayinger:
  Two Phase Flow and Heat Transfer in the Power and Process
  Industries
  McGraw-Hill Book Company (1981).
- John G. Collier:
  Convective Boiling and Condensation
  McGraw-Hill International Book, second edition (1981).
- Shoichiro Nakamura:
Computational Methods in Engineering and Science with Applications    to Fluid Dynamics and Nuclear Systems
  Ohio State University, A Wiley-Inter-Science Publications (1977).
- A. Gourdin and M. Boumahrat:
  Methodes Numeriques Appliquees
  Office des Publications Universitaires, Alger (1991).
- Safety and Licensing Guide-Book:
  Research Reactor Core Conversion from the Use of Highly Enriched
  Uranium to the Use of Low Enriched Uranium Fuels
  Volume 3, Appendix-G, IAEA (1990).

- B. Baggoura and A. Bousbia Salah:
  THACT-RR - User's Guide & Validation/Benchmarking
  Input Data Description for the THACT-RR Code
  Ministere de l'Education Nationale (June 1993).

11. MACHINE REQUIREMENTS:  The sample problem requires less than 200 Kbytes.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:  VAX/VMS.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS:

15. NAME AND ESTABLISHMENT OF AUTHORS

          B. Baggoura
     Centre de Radioprotection de et Surete (C.R.S.)
     2 Boulevard F. Fanon
     BP 1017 Alger Gare, Alger 16000, Algeria

          A. Bousbia Salah
     Centre de Developpement des Systems Energetiques (C.D.S.E.)
     BP 180 Ain-Oussera, 17200 Djelfa, Algeria

source program   mag tapeTHACT.FOR THACT-RR Source File             SRCTP
test-case output mag tapeTHACT2.OUT THACT-RR Sample Output          OUTTP
test-case output mag tapeTHACT1.OUT THACT-RR Sample Output          OUTTP
test-case data   mag tapeTHACT1.DAT THACT-RR Test_case Data         DATTP
test-case data   mag tapeTHACT2.DAT THACT-RR Test_case Data         DATTP
user's guide             User's Guide (June 1993)                   WRKPT