THERMODYNAMICS OF IDEAL-GASES UNDER SHEAR - A MAXIMUM-ENTROPY APPROACH

The maximum-entropy formalism is used here as a basis of a thermodynam ic description of ideal gases under shear. We have obtained expression s for the entropy and the equations of state in nonequilibrium steady states characterized by a given shear viscous pressure and have identi fied in physical terms the Lagrange multiplier conjugated to the visco us pressure. Our results for those thermodynamic quantities generalize previous expressions which were limited to second order in the shear viscous pressure. These results show a reduction of the shear viscosit y at high shear rates and also show how previous results of nonequilib rium molecular dynamics could be compatible with our thermodynamic ana lysis.