Stress Intensity Simulation of Printed Circuit Heat Exchanger for S-CO2 Brayton Cycle

A series of studies pay attention to the thermal-hydraulic performance of the Printed circuit heat exchanger (PCHE) coupled to Supercritical carbon dioxide cycles. However, the structural integrity requirement cannot be ignored moreover in view of the non-repairable PCHE core. In this study, the thermal-hydraulic performance under a specified condition and the stress intensity distribution of PCHE are investigated numerically, including the impact by pressure difference, temperature, temperature difference and the thermo-mechanical characteristics under combined thermal loading and mechanical loading. The results indicate that stress intensity of the PCHE arise from both pressure load and temperature gradients. Stress caused by pressure load is more obvious than thermal stress. Pressure difference has significant influence on stress intensity distribution. The stress intensity values at different position along the flow direction are almost invariable when wall temperature differences keep same among these sections. Under the practical conditions, the stress near the tips of the high pressure side need to be most concerned about, secondly to the middle of the bottom of the same side. This research work can provide theoretical guidance for structure integrity assessment of PCHE for S-CO
₂
Brayton cycle.