W. Muschik
Internal Variables in Non-Equilibrium Thermodynamics
J. Non-Equilib. Thermodyn. 15, 1990, 127-137
The concept of internal variables is introduced axiomatically into
nonequilibrium thermodynamics for avoiding small state spaces showing
after-effects. The connection between internal variables, projectors
onto equilibrium subspace, and accompanying procecesses is
demonstrated for discrete systems. Relaxation variables, chemical
reactions, and Kestin-Ponter's model of plasticity are discussed.