PSI - Issue 60

P.A. Jadhav et al. / Procedia Structural Integrity 60 (2024) 631–654 P.A. Jadhav et. al./ Structural Integrity Procedia 00 (2019) 000 – 000

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This paper has presented an evaluation of the probability of DHC initiation from a volumetric flaw and also the probability of BBL for the PT of a PHWR. The random variables considered in the Monte Carlo based evaluations are flaw dimensions and the necessary material properties. It is shown that the risk for BBL is very low. The probability of DHC initiation was reported on a parametric evaluation on crack geometry, residual stress and hydrogen concentration in the Zr alloy. The statistics for the TWC which gets formed from a growing DHC sub-surface crack, is also generated. The AGMS is the main leakage detection system in the PHWR. It has a very high sensitivity and any leakage coming out of the TWC is expected to be detected. The statistical estimates of time required for the TWC to become equal to CCL is also reported. It is reported that the reactor can be economically shut down, cooled and depressurized in about l0 hours from first penetration Walker (1990). 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