Heat and mass transfer in a rarefied gas confined between its two parallel condensed phases

Abstract

The heat and mass transfer in a rarefied gas between its two parallel condensed phases is considered on the basis of linearized and non-linear S-model kinetic equations. The profiles of the macroscopic parameters in the gap between gas-liquid interfaces are obtained for several Knudsen numbers and for the cases of complete and non-complete evaporation and condensation. The linearized Navier-Stokes equations and energy equation, subjected to the temperature and pressure jump boundary conditions, are solved analytically and the expressions for the macroscopic parameters are obtained. The comparison of three approaches allowed us to establish the limit of the application of the linearized approaches in term of the saturation temperature ratio between the condensed phases.

Kinetic modelling of evaporation and condensation phenomena around a spherical droplet

“…The same qualitative behavior was found in Ref. [28], in which the problem of noncomplete evaporation-condensation between two parallel condensed phases was simulated. For instance, in case of δ=10, the numerical results obtained from the kinetic equation at the interface, given in Tables 5 and 6, show a difference of about 93% for the bulk velocities u (n) and u (T ) , and heat flux q (n) , when the evaporation-condensation coefficient varies from 1 to 0.1.…”

“…[25] derived several useful correlations for the evaporation rate and in-terfacial heat transfer and compared them with the numerical results of [26]. The question on the limits of the applicability of the linearized kinetic type equation for the simulation of the evaporation and condensation phenomena are discussed only in the case of the plane geometry [27,28]. In addition, the influence of the non-complete evaporation-condensation was very often ignored.…”

Sublimation and deposition in gaseous mixtures

“…This phenomenon called inverted temperature profile was found previously in the numerical modeling of the evaporation and condensation phenomena, see Refs. [42,50,43].…”

“…The analogous formulation was considered in Refs. [42,43] in the case of evaporation and condensation. Finally, if we assume that the second species is also non-condensable, then the problem will be the same as that considered in Ref.…”