ML091940513
| ML091940513 | |
| Person / Time | |
|---|---|
| Issue date: | 10/22/1985 |
| From: | Han J, Marino G Office of Nuclear Regulatory Research |
| To: | |
| Han, James T. | |
| References | |
| Download: ML091940513 (9) | |
Text
SEVERE ACCIDENT CODE DEVELOPMENT PROGRAM JAMES T, HAN AND GEORGE P. MARINO U.S. NUCLEAR REGULATORY COMMISSION PRESENTED AT THE THIRTEENTH WATER REACTOR SAFETY RESEARCH INFORMATION MEETING GAITHERSBURG, MARYLAND OCTOBER 22-25, 1985
ABSTRACT SEVERE ACCIDENT CODE DEVELOPMENT PROGRAM James T. Han and George P. Marino U.S. Nuclear Regulatory Commission This paper sunmarizes the scope and status of the Severe Accident Code Development Program, which is part of the NRC Severe Fuel Damage and Source Tenn (SFD/ST) Research Program.
The Program consists of the development and assessment of the state-of-the-art mechanistic computer codes:
SCDAP/RELAP5 and MELPROG/TRAC.
The SCDAP/RELAP5 code has been developed to make detailed analysis of the SFD/ST experiments and also to analyze the progression of the TMI-type "recovered" accidents in the reactor coolant system (RCS) of nuclear power plants.
The code is currently operational on a CRAY-I computer and was used successfully to make a pretest prediction for the LOFT FP-2 core damage test with the entire RCS modeled.
The MELPROG/TRAC code is being developed to analyze severe accident progression in the RCS up to and including vessel failure.
Code assessment and improvement for both codes will continue in the near future.
INTRODUCTION 1
THE SEVERE ACCIDENT CODE DEVELOPMENT PROGRAM PRESENTED IN THIS PAPER IS PART OF THE NRC SEVERE FUEL DAMAGE AND SOURCE TERM (SFD/ST) RESEARCH PROGRAM, 1
THE PROGRAM CONSISTS OF THE DEVELOPMENT AND ASSESSMENT OF THE STATE-OF-THE-ART MECHANISTIC COMPUTER CODES, SCDAP/RELAP5 AND MELPROG/TRAC, FOR ANALYZING SEVERE ACCIDENT PROGRESSION IN THE REACTOR COOLANT SYSTEM (RCS)
OF NUCLEAR POWER PLANTS, 1
THE CODES WILL PREDICT THE TIMING AND MAGNITUDE OF THE RELEASE OF FISSION PRODUCTS, HYDROGEN, AND STEAM/WATER TO THE CONTAINMENT AND/OR AUXILIARY BUILDING,
I SEVERE ACCIDENTS IN A NUCLEAR POWER PLANT:
CONTAINMENT/AUX, BLDG, RCS (VESSEL+
COMPONENTS)
RADIOACTIVE MATERIALS HYDROGEN STEAM/WATER OTHER MATERIALS AMBIENT AIR RADIOACTIVE MATERIALS (SOURCE TERM)
THE SEVERE ACCIDENT ANALYSIS CODES:
SCDAP/RELAPS AND MELPROG/TRAC
- ANALYZING SEVERE ACCIDENT PROGRESSION IN THE REACTOR COOLANT SYSTEM (RCS)
- PROVIDING BOUNDARY CONDITIONS TO THOSE CODES MODELING CONTAINMENT BEHAVIOR AND INTEGRITY, AND SOURCE TERM 1
SUPPORTING EXPERIMENTAL PROGRAMS - PBF, NRU, ACRR, AND CORA
MODULAR STRUCTURE OF SEVERE ACCIDENT ANALYSIS CODES RECOVERED ACCIDENT, AND DETAILED MODELING VESSEL-FAILURE OF SFD/ST EXPERIMENTS SEVERE ACCIDENTS SCDAP/RELAP5 MELPROG/TRAC FUNCTION CORE DAMAGE AND MELT SCDAP MELPROG (HYDROGEN RELEASE INCLUDED)
THERMAL-HYDRAULICS RELAP5 TRAC, MELPROG FISSION PRODUCT RELEASE PARAGRASS/
VICTORIA AND TRANSPORT TRAP-MELT VESSEL FAILURE MELPROG MATERIAL PROPERTIES MATPRO MATPRO
SEVERE ACCIDENT PROGRESSION IN THE RCS OF A NUCLEAR PLANT RECOVERED ACCIDENTS, AND DETAILED MODELING VESSEL-FAILURE OF SFD/ST EXPTS.
SEVERE ACCIDENTS SCDAP/RELAP5 MELPROG/TRAC NORMAL OPERATION RELAP5 TRAC-PFl ACCIDENT/TRANSIENT RELAP5 TRAC-PFl CORE UNCOVERY RELAP5 TRAC-PFl CORE DAMAGE AND MELT SCDAP/RELAP5 MELPROG/TRAC STEAM GENERATION BY SCDAP/RELAP5 MELPROG/TRAC CORE DEBRIS IN LOWER PLENUM VESSEL FAILURE MELPROG/TRAC
SCOPE OF SEVERE ACCIDENT CODE DEVELOPMENT PROGRAM 1
DEVELOP SCDAP AND MELPROG 1
DEVELOP STAND-ALONE CODES - PARAGRASS, TRAP-MELT, VICTORIA, AND MATPRO 1
MODIFY EXISTING THERMAL-HYDRAULIC CODES - RELAP5, TRAC 1
INTEGRATE THESE CODES TO PROVIDE SYSTEM-WIDE SEVERE ACCIDENT ANALYSIS 1
ASSESS THE CODES BY COMPARING CALCULATIONS WITH EXPERIMENTAL AND ANALYTICAL RESULTS
CODE STATUS THE SCDAP/RELAP5 CODE (INCLUDING TRAP-MELT) IS OPERATIONAL ON A CRAY-I COMPUTER, IT WAS USED SUCCESSFULLY TO MAKE A PRETEST PREDICTION FOR THE LOFT FP-2 CORE DAMAGE TEST WITH THE ENTIRE RCS MODELED, STAND-ALONE SCDAP CODE HAS BEEN AND WILL CONTINUE TO BE USED TO ANALYZE SFD/ST EXPERIMENTS, A PRELIMINARY VERSION OF MELPROG HAS BEEN RELEASED:
1-0 THERMAL HYDRAULICS, AND VICTORIA NOT INCLUDED, 1
MELPROG NOW HAS 2-0 THERMAL HYDRAULICS FOR THE VESSEL, IT WILL INCLUDE VICTORIA AND WILL BE COUPLED WITH TRAC TO MODEL THE ENTIRE RCS, 1
CODE ASSESSMENT, IMPROVEMENT, AND DEBUGGING WILL CONTINUE,
I SUPPORT AND INTERACTION WITH OTHER PROGRAMS MECHANISTIC CODES SCDAP/RELAPS, MELPROG/TRAC
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