Random vibration response calculation and fatigue analysis of thin-walled structures under heat flux environment

For the problem of random vibration stress response variation law and fatigue failure time of thin-walled structures under high-speed heat flux environment, numerical simulation calculations and high temperature random vibration tests were carried out. By comparing the simulation results with the experimental results, the modal error was less than 2.8% and the stress response error was less than 4%. The structural fatigue failure time error was less than 3430s, verifying the reliability of the numerical simulation. Based on the coupled FEM/BEM(finite element method/boundary element method) theoretical, the Fluent software was used to simulate the high-speed heat flux environment, and the calculation of the random vibration stress response of the thin-walled structure under high-speed heat flux environment was realized. The dynamics response and fatigue failure time of thin-walled structures under different vibration magnitudes and heat flux environments were obtained. The variation law of structural thermal random vibration stress response and fatigue failure time under different environment temperatures and flux rates was analyzed, and the reasons for these changes were explained. The work completed can provide a reference for the estimation of thermal random vibration fatigue failure time of thin-walled structures under high-speed heat flux environment. © 2020, Editorial Department of Journal of Aerospace Power. All right reserved.