An inverse meshfree thermoelastic analysis for identification of temperature-dependent thermal and mechanical material properties

In many practical problems, a body is subjected to a thermal load and experience a temperature change. In some cases, the temperature change can be very high and it would be better to consider thermal and mechanical properties as a function of temperature whereas in many cases, temperature-dependent thermal and mechanical properties are unknown. In this article, an inverse method is presented for identification of the thermal conductivity, the specific heat, the coefficient of thermal expansion, and the elastic modulus, where all the properties are considered as functions of temperature. It is assumed that these four material properties are simultaneously unknown. In the proposed method, the unknown parameters of the inverse problem are calculated using measured data from a transient thermomechanical experiment. Sensitivity analysis is carried out by an analytical direct differentiation method and a meshfree technique. Several important factors affecting the identification of the thermal and mechanical properties, such as the error of measuring sensors, the number of sensors, and the number of sampling data are studied in the numerical analyses. The obtained results show that identification of the properties using the proposed inverse method can be achieved with a suitable accuracy even in the cases with measurement errors.