Failure probability evaluation for a weld of the heat pipe in the Mega-Power heat pipe cooled reactor

• Published in: Annals of nuclear energy Vol. 177; p. 109324
• Main Authors: Xu, Xinyan, Liang, Qingzhu, Peng, Changhong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-11-2022
• Subjects: Mega-Power heat pipe cooled reactor; Probabilistic fracture mechanics; Stress corrosion cracking; Weld failure probability; Stress corrosion cracking; Mega-Power heat pipe cooled reactor; Probabilistic fracture mechanics; Weld failure probability
• ISSN: 0306-4549; 1873-2100
• DOI: 10.1016/j.anucene.2022.109324

•A probabilistic fracture mechanics analysis code considering the unique characteristics of heat pipe is developed.•Failure probability evaluation for a specific heat pipe and uncertainty analysis of input parameters are carried out.•Failure probabilities under conditions of multiple heat pipe failures are compared.
Heat pipe cooled reactor, featuring using heat pipes as passive cooling, has received renewed interest. A Monte-Carlo-based probabilistic fracture mechanics analysis code, including crack initiation and propagation model, is developed to estimate the probability of failure at a weld in the heat pipe due to stress corrosion cracking (SCC), fatigue, and high temperature creep. The application of this code is demonstrated on the heat pipe of the Mega-Power rector. The results show that SCC is more important in accelerating heat pipe failure than fatigue and high temperature creep. Failure probabilities under the condition of one or two adjacent failed heat pipes are abnormally close. Uncertainty analysis for input parameters proves initial crack size is more sensitive than temperature. This also provides a reference for heat pipe design and safety assessment of whole reactor.