RSICC CODE PACKAGE PSR-423

 

1.  NAME AND TITLE

RELAP5/MOD1:           LWR Loss of Coolant Analysis.

 

May 2007 - The U.S. Nuclear Regulatory Commission regards RELAP5/MOD1 as obsolete. RSICC retains this package for historical purposes. Those interested in running RELAP are referred to web page http://www.nrccodes.com/ for information on current versions available through the CAMP agreement.

 

2.  CONTRIBUTORS

EG&G Idaho Inc., Idaho Falls, Idaho, through the Energy Science and Technology Software Center, Oak Ridge, Tennessee.

 

3.  CODING LANGUAGE AND COMPUTER

RELAP5/MOD1/029: Fortran IV (90%) and COMPASS (10%) CDC CYBER 176; CDC (P00423C017600).

RELAP5/MOD1/025: Fortran 77 (99%) and MACRO (1%); DEC VAX11 (P00423DVX1100).

RELAP5/MOD1/025: Fortran 77 (99%) and BAL (1%) (IBM3081); IBM 3033 (P00423I303300); NEADB identifier: NESC0917/18.

 

4.  NATURE OF PROBLEM SOLVED

RELAP5 was developed to describe the behavior of a light water reactor (LWR) subjected to postulated transients such as loss of coolant from large or small pipe breaks, pump failures, etc. RELAP5 calculates fluid conditions such as velocities, pressures, densities, qualities, temperatures; thermal conditions such as surface temperatures, temperature distributions, heat fluxes; pump conditions; trip conditions; reactor power and reactivity from point reactor kinetics; and control system variables. In addition to reactor applications, the program can be applied to transient analysis of other thermal‑hydraulic systems with water as the fluid.  This package contains RELAP5/MOD1/029 for CDC computers and RELAP5/MOD1/025 for VAX or IBM mainframe computers.

 

5.  METHOD OF SOLUTION

Hydrodynamic equations are advanced in time using a semi‑implicit, linearized method. Heat conduction is approximated by finite differences and advanced by the Crank‑Nicolson scheme. A modified Runge‑Kutta technique is used to solve the reactor kinetics equations. The interaction among hydrodynamics, heat conduction, trips, reactor kinetics, and the control system is explicit.

 

6.  RESTRICTIONS OR LIMITATIONS

Dynamic allocation of storage is used for all problem-dependent data.

 

7.  TYPICAL RUNNING TIME

The EDHTRK sample problem takes 20 CP seconds on a CDC Cyber 176 and 39 CP seconds on a CDC Cyber 175 and 44 CPU seconds on IBM 3081.  The EDHTRK sample problem takes 14 CP seconds on a Dec Micro  VAX11 with floating point accelerator and 20 CPU minutes on a DEC Vax11/785.

 

8.  COMPUTER HARDWARE REQUIREMENTS

CDC Cyber 176 and CDC 7600; VAX; IBM mainframes.

 

9.  COMPUTER SOFTWARE REQUIREMENTS

NOS/BE (CDC CYBER 176), SCOPE 2.1 S(CDC7600), NOS 2.2(CDC CYBER175);  VMS 4.5 (DEC VAX11); or MVS (IBM3081, IBM3033); VM/CMS (IBM4331).

 

10. REFERENCES

V. H. Ransom, R. J. Wagner, J. A. Trapp, K. E. Carlson, D. M. Kiser, H‑H. Kuo, H. Chow, R. A. Nelson, and S. W. James, “RELAP5/MOD1 Code Manual Volume 1: System Models and Numerical Methods,” NUREG/CR‑1826 (EGG‑2070) (March 1982).

R. J. Wagner, K. E. Carlson, D. M. Kiser, V. H. Ransom, H‑H. Kuo, H. Chow, J. A. Trapp, S. W. James, and D. G. Hall, “RELAP5/MOD1 Code Manual Volume 2: Users Guide and Input Requirements,” NUREG/CR‑1826 (EGG‑2070) (March 1982).

 R.A. Riemke, H. Chow, and V.H. Ransom, “RELAP5/MOD1 Code Manual Volume 3: Checkout Problems Summary,” EGG‑NSMD‑6182 (February 1983).

M.P. Paulsen, C.E. Peterson, K.R. Katsma, “Feasibility Study for Improved Steady‑State Initialization Algorithms for the RELAP5 Computer Code, Phase I Improved Steady‑State Initialization Algorithms for Computer Codes,” NUREG/CR‑6035 (April 1993).

EG&G Idaho, “NRTS Environmental Subroutine Manual” (December 9, 1980).

 D. G. Hall and E.C. Johnson, “RELAP5/MOD1 Quick Reference Manual,” EGG‑CDD‑6027 (October 1982).

“Environmental Library Installation Procedures, EG&G Note” (September 1983).

W. Kolar and W. Brewka, “The IBM‑Version of RELAP5/MOD1,” EUR 6977 EN (1983).

M. Birgersson, “RELAP5/MOD1/029, NESC No. 917.C176,” NESC Note 85-36 (December 24, 1984).

M. Birgersson, “RELAP5/MOD1/029, NESC No. 917.C176B,” NESC Note 85-37 (December 24, 1984).

 

11. CONTENTS OF CODE PACKAGE

Included in the package are the referenced documents and one diskette (for CDC or IBM version) or two diskettes (for VAX version) containing source and test cases written in self-extracting DOS files.

 

12. DATE OF ABSTRACT

July 1999, revised October 1999, June 2007

 

KEYWORDS:  LOCA; HEAT TRANSFER; THERMAL HYDRAULICS; NUCLEAR SAFETY