Radiative deformation

An infinitesimal change δQδQ in heat flux Q is shown, in terms of entropy flux Ψ=Q/T,Ψ=Q/T, to have two parts, δQ=TδΨ+ΨδT.δQ=TδΨ+ΨδT. 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. Thermodynamic arguments are extended to transport phenomena. It is shown that the thermal part of the rate of local entropy generation is related to the local rate of thermal deformation by s′′′=−ψi/T(∂T/∂xi),s′′′=−ψi/T(∂T/∂xi), where ψi=qi/T,ψi=qi/T, ψiψi being the rate of entropy flux vector, and qiqi the rate of heat flux vector. The part of this generation related to radiation is illustrated in terms of an example. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70807/2/JAPIAU-87-6-3093-1.pd