Modified Fourier law, comparison of two approaches

Abstract

The objective of this note is to compare two different models leading to modified Fourier laws. The first model uses the concept of semi-empirical temperature, the second one is built in the framework of extended thermodynamics. For both approaches three experimental curves, namely the specific heat, heat conduction coefficient and second sound speed, all given in terms of the absolute temperature, determine the models. Conditions under which both models lead to similar results are formulated.