Thermal-mechanical coupled stress prediction of printed circuit heat exchanger in the supercritical CO2 Brayton cycle

作者：Junlin Chen, Wenhai Du, Keyong Cheng, Xunfeng Li, Xiulan Huai, Jiangfeng Guo, Pengfei Lv, Hongsheng Dong · 发表于：Case Studies in Thermal Engineering · 年份：2025 · DOI：10.1016/j.csite.2025.106521 · 被引用次数：9 · 研究领域：Heat Transfer and Optimization、Refrigeration and Air Conditioning Technologies、Heat transfer and supercritical fluids

Printed circuit heat exchanger (PCHE) is widely recognized as the most promising heat exchanger for supercritical CO 2 (SCO 2 ) Brayton cycle. Stress assessment is critical to ensuring the safety and longevity of PCHE. This study addresses a critical gap in the thermal-mechanical stress assessment of PCHE for SCO 2 Brayton cycles by developing novel quantitative models to predict equivalent stresses at semicircular channel tips. Unlike conventional ASME codes, which overlook thermal stress, the pseudo-2D ANSYS Workbench model integrating both thermal and mechanical stresses, was used to offer a comprehensive evaluation. Key structural parameters (channel diameter, plate thickness, ridge thickness) and operational parameters (pressure, temperature difference) were analyzed. The results reveal that mechanical stress is most sensitive to cold-side pressure, while thermal stress correlates linearly with temperature gradients. Dimensional analysis yielded predictive formulas for thermal stress (±13.3% error) and mechanical stress (±14.3% error), validated against finite element method results. A backpropagation neural network further improved prediction accuracy (errors <10%). The proposed models streamline PCHE design verification and dynamic control optimization, ensuring safer and more efficient SCO 2 cycle operation. This research advances sustainable energy systems by providing reliable tools for PCHE stress assessment, with potential applications in solar, nuclear, and waste...