Variational description of body motion under the action of an external field in a condensing medium with drag (Q1409082)

A body moves through a two-phase medium in an external field with potential \(U(z)\). The liquid phase condenses on the body surface, and the gas phase features drag. Equation of motion and condensation kinetics equation are considered, and in the asymptotic mode the condensation leads to uniformly accelerated motion. Stability of the liquid film with given viscosity and surface tension is evaluated. A variational description of the problem is given and reasons and conditions making it possible to use this description for irreversible processes are discussed.