Thermodynamics of irreversible processes in rotating systems

Abstract

The general entropy balance equation for a rotating system containing a mixture of (charged and uncharged) components is calculated and the influence of centrifugal force and Coriolis force on the entropy production is considered.

From the general formalism the equations for mechanical equilibrium are derived. As a further specification of this case, Svedberg's equations for the determination of molecular masses of uncharged particles are derived, viz., the equation for the sedimentation equilibrium and (introducing the boundary condition of vanishing volume flow) the equation for the sedimentation rate in the ultracentrifuge. A proper definition of the diffusion coefficient is given.