文献类型：期刊文献

英文题名：A probabilistic framework for the failure assessment of plate-fin heat exchangers under creep-fatigue interactions

作者：Chen, Qi[1];Wang, Xiaoxiao[1];Chen, Haofeng[1,2,3];Xuan, Fuzhen[1];Jia, Guodong[4]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Key Lab Pressure Syst & Safety DOE, 130 Meilong Rd, Shanghai 200237, Peoples R China;[2]Southwest Petr Univ, Sch Mechatron Engn, Chengdu 610500, Peoples R China;[3]Shanghai Inst Aircraft Mech & Control, 130 Meilong Rd, Shanghai 200237, Peoples R China;[4]China Special Equipment Inspect & Res Inst, 2 Bldg,Heping Rd, Beijing 100000, Peoples R China

年份：2025

卷号：329

外文期刊名：ENGINEERING STRUCTURES

收录：;EI(收录号：20250417767058);WOS:【SCI-EXPANDED(收录号:WOS:001421610700001)】；

基金：The authors are grateful for the supports provided by the National Key R&D Program of China (2023YFF0614903) and the Shanghai Gaofeng Project for University Academic Program Development. The paper is also sponsored by the National Natural Science Foundation of China (52375145 and 52321002) and the China Postdoctoral Science

语种：英文

外文关键词：Creep-fatigue; Probabilistic assessment; Direct method; Surrogate model; PFHE

摘要：The structural integrity of high-efficiency plate-fin heat exchangers (PFHE) in fourth-generation nuclear reactors faces challenges from creep-fatigue interactions and multi-source uncertainties. This paper proposes an integrated framework for probabilistic creep-fatigue assessment that incorporates direct methods and artificial neural networks (ANN). The developed probabilistic Linear Matching Method (pLMM) framework is employed for the reliability assessment and reliability-based design optimization of PFHE, with three levels of creep-fatigue interactions considered. In detail, the deterministic creep-fatigue responses of the structure under cyclic thermalmechanical loadings are obtained utilizing the extended Direct Steady Cyclic Analysis, which accounts for creepfatigue interactions at both the mechanical behaviour and damage levels. Observations of the damage composition at the critical locations indicate that fatigue damage plays a dominant role in the creep-fatigue failure of PFHE, while a transition in the dominant mode occurs when parameter random fluctuations are introduced. For probabilistic analysis, a robust ANN-based surrogate model is established to relate input parameters to key responses, following the quantitative description of the individual impacts of multiple parameter uncertainties on lifespan. Combined with Monte Carlo simulation, the statistical distributions of key responses, including damage and lifespan, are obtained. In terms of investigating the dominant creep-fatigue modes under uncertainties, the probability of each mode is quantitatively displayed, and the creep-fatigue interaction mechanism at the statistical level is clarified. On the other hand, the lifespan evaluation curve based on multigrade reliability is created for engineering applications. Furthermore, the study of parameter distributions shows that a higher coefficient of variation significantly reduces the structural reliability of PFHE. Lastly, a double-loop procedure within the pLMM framework is proposed for the reliability-based structural optimization. The optimized structure exhibits satisfactory reliability performance while achieving lightweighting goals.