The thermal shock resistance prediction of porous ceramic sandwich structures with temperature-dependent material properties

Abstract

A general numerical model to predict the thermal shock resistance of porous ceramic sandwich (PCS) structures with temperature-dependent material properties is developed. Knowledge of the temperature distribution and associated thermal stress in PCS panel is determined by the finite element method of coupled thermoelasticity. The present work considers the hot/cold shock induced center/edge cracks and measures the time-varied thermal stress intensity factors at the crack tip area. The roles of crack length, relative density of foam core, thermal shock load and geometric parameters of the PCS structures are examined. Moreover, fracture failure analysis of the whole PCS structures is carried out and crack propagation manners are detected. The thermal shock resistance curves of the structures are provided and the critical thermal shock temperatures are estimated for any selected characteristic materials. Results reveal that the thermal shock resistance of the PCS structures will be dramatically underestimated with the ignorance of temperature-dependent material properties. The analysis model of this paper provides a rapid prediction of thermal shock behavior of PCS structures at arbitrary temperatures.