Thermo-mechanical analysis of a cylindrical tube under internal shock loading using numerical solution

Abstract

Thermo-mechanical shock wave in tube has many applications in aerospace/petroleum structures that brings up many challenges in repetitive, traveling, impulsive loading, and thermo-mechanical fatigue. The mechanical shock waves can cause oscillating strains in the tube wall, which can be several times higher than the equivalent static strains. The overall thermo-mechanical stresses after several loading–unloading processes in the engine may produce some discontinuities which may result in catastrophic fracture. In the current study, the resulting mechanical and thermal stresses have been assessed using numerical simulations. An axisymmetric finite element model of thermo-mechanical shock wave was developed using capabilities of commercial package ABAQUS for the preliminary analysis presented in this paper. Also, effects of different boundary condition types on tube wall response were investigated. The temperature field inside the engine was determined and presented in the form of a fixed value. In the numerical simulations, the mechanical and thermal displacements were computed separately and they are compared with available numerical and experimental results. Finally, the combined effects of mechanical and thermal stresses caused by thermo-mechanical shock wave have been simulated. The results of simulating coupled thermal stress showed that thermal shock caused by internal thermo-mechanical shock wave in tubes produces significant thermal stress.