The problem on nonstationary growth and evaporation of drops

A general theory is suggested of nonstationary processes of evaporation and condensation growth of a quiescent spherical drop, when the boundary conditions in the case of simultaneous solution of nonstationary equations of diffusion and heat conduction include jumps of concentration and temperature on the Knudsen layer. Integral Laplace transforms are used to derive a general expression for the concentration distribution, as well as equations for the temperature fields on the drop surface and in the surrounding medium. Their dependence on the composite coefficients of concentration and temperature jumps is observed. The asymptotic behavior of general equations of the fields of concentration and temperature, as well as of the distributions of the rate of temperature variation on the drop surface, is investigated. A general (for all times) expression for the rate of variation of the drop radius is derived and investigated using asymptotic expansions, and the limits of validity of some results of previous theories are established.