A Variational Principle of Steady-State Transport Processes
A variational principle of steady-state transport processes has been derived from a basic inequality in the macroscopic theory of nonequilibrium thermodynamics . The extremum property of a variational integral 3> is established from the stability of steady state, and the existence of $ is discussed from the integrability of a Pfaffian differential equation. The extremum principle presented here may be called the principle of minimum thermokinetic potential and may be regarded as the generalization of the principle of minimum entropy production for the case of nonlinear fluxes. For illustration, a simple heat-conduction problem has been given as an example.