Transient thermal stress analysis for a circumferentially cracked hollow cylinder based on memory-dependent heat conduction model

摘要

A newly proposed memory-dependent heat conduction model is applied to investigate the transient thermal stress problem of a hollow cylinder containing an embedded internal or surface circumferential crack. The cylindrical system is subjected to thermal shock at the inner surface and with an insulated outer surface. Laplace integral transform is adopted to obtain the analytical solutions for temperature and thermal stress field in an uncracked hollow cylinder. Then based on the superposition method, the axial stress with minus sign is applied on the crack surface to form a mode I crack problem. Integral transform techniques are employed to reduce the mixed boundary value problem to a singular integral equation. Finally, the effects of time delay, kernel function and crack geometry on the transient temperature, thermal axial stress and thermal stress intensity factors are analyzed for embedded internal and surface cracks. The results show that the thermal stress state at the crack tip is different when the three parameters take different values, which is important to make predictions regarding the stability of crack growth, thermal fatigue life, etc.