A computer model for probabilistic leak-rate analysis of nuclear piping and piping welds

Book · Wed Nov 01 00:00:00 EST 1995

OSTI ID:122624

Rahman, S; Ghadiali, N; Wilkowski, G; Paul, D ^[1]

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1. Battelle Memorial Institute, Columbus, OH (United States). Engineering Mechanics Group

This paper describes the development of a computer code titled PSQUIRT for probabilistic evaluation of leak rate in nuclear piping. It is based on (1) Henry-Fauske model of two-phase flow for thermal-hydraulic analysis and (2) estimation model for elastic-plastic fracture-mechanics analysis. In both analyses, uncertainties arise due to the incomplete knowledge of the crack-morphology variables and statistical scatter of the pipe material properties. The relevant parameters required to conduct these analyses were modeled as random variables. Henceforth, the above thermal-hydraulic and fracture-mechanics models were put in a probabilistic format to allow statistical variability of input and determination of their effects in pipe fracture and leak-before-break (LBB) evaluations. A Monte Carlo simulation technique was used to perform the probabilistic analysis. Numerical examples are presented to illustrate the capabilities of the PSQUIRT code. Probabilistic analyses were performed by PSQUIRT for a stainless steel and a carbon steel pipe. Histograms were developed for leakage rate and flaw size in these pipes for LBB applications. The results suggest that the variabilities of flaw size and leak rate can be significant due to statistical scatter of crack-morphology parameters. Using these histograms, the subsequent fracture stability of a leaking crack can be evaluated by either a deterministic or a probabilistic method.

• OSTI ID: 122624
• Report Number(s): CONF-950740-; ISBN 0-7918-1335-5; TRN: 95:024243
• Resource Relation: Conference: Joint American Society of Mechanical Engineers (ASME)/Japan Society of Mechanical Engineers (JSME) pressure vessels and piping conference, Honolulu, HI (United States), 23-27 Jul 1995; Other Information: PBD: 1995; Related Information: Is Part Of Fatigue and fracture mechanics in pressure vessels and piping. PVP-Volume 304; Mehta, H.S.; Wilkowski, G.; Takezono, S.; Bloom, J.; Yoon, K.; Aoki, S.; Rahman, S.; Nakamura, T.; Brust, F.; Yoshimura, S. [eds.]; PB: 594 p.
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
22 NUCLEAR REACTOR TECHNOLOGY
99 MATHEMATICS
COMPUTERS
INFORMATION SCIENCE
MANAGEMENT
LAW
MISCELLANEOUS
NUCLEAR POWER PLANTS
PIPES
P CODES
LEAKS
WELDED JOINTS
FRACTURES
FRACTURE MECHANICS
PROBABILISTIC ESTIMATION
STAINLESS STEEL-304
STEEL-ASTM-A516
THEORETICAL DATA
CORROSION FATIGUE
COMPARATIVE EVALUATIONS
LEAK TESTING