Determination of Thermal Conductivities of Transversally Isotropic Conductive Materials at High Temperatures

Abstract

A computational and experimental method for determining the thermal conductivity of transversely isotropic conductive materials at high temperatures based on solving the inverse problem in a thermoelectrically coupled formulation has been developed. The influence of the degree of anisotropy of properties on the temperature distribution in the cross-sections of the working zones of cylindrical samples, where heat is generated by passing an electric current and is removed by convection and radiation on the side surfaces, was investigated for isotropic and quasi-isotropic graphites, unidirectionally reinforced carbon–carbon composite material (essentially anisotropic) and highly oriented pyrographite (strongly anisotropic). The developed method was tested using data obtained as a result of numerical solution of a direct thermoelectrically coupled problem for weakly and significantly anisotropic materials. A comparison of solutions for constant and linear local approximations of the dependences of thermal conductivity on temperature was carried out.