On energy and entropy inflows in the theory of heat conduction

摘要

In continuum mechanics, both energy and entropy inflows consist of a scalar source term and a vectorial influx term; customarily, the energy inflow is assumed equal to the entropy inflow multiplied by the absolute temperature. Here, working for simplicity within the framework of the standard theory of heat conduction, an argument is given in support of taking the source terms proportional; moreover, it is proved that the same must be done for influx terms in case conduction is isotropic, but generally not in case of inferior symmetry.