On the Variation Principle in the Kinetic Theory of Dense Gases, I.

Abstract

The variation principle in the kinetic theory of gases is extended to the case of a dense gas made of rigid-sphere molecules with the finite radius. The solution of Enskog's first approximation equation for the dense gas of rigid-sphere molecules is derived from the variation principle. The local entropy production per unit time is the maximum in this variational principle. The correction to the entropy due to imperfectness of the gas is calculated from the virial expansion of the equation of state for a rigid-sphere gas.