An infinitesimal change in heat flux Q is shown, in terms of entropy flux $Ψ=Q/T$ to have two parts, $dQ=TdΨ+ΨdT,$ the first part being the thermal displacement and the second part being the thermal deformation. Only the second part dissipates into internal energy and generates entropy. This generation is shown to be $dΠ=Ψ/TdT.$ Thermodynamic arguments are extended to transport phenomena. It is shown that a part of local rate of entropy generation is related to local rate of thermal deformation by $s′′′=−ψi/T∂T/∂xi,$ where $ψi=qi/T,qi$ being the rate of heat flux.

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