KINETICS OF INTENSE EVAPORATIVE MASS-TRANSFER THROUGH A POROUS LAYER

A kinetic problem of mass transfer in a model porous body in the proce ss of intense evaporation (condensation) and vapour escape into a vacu um is considered. Two computational methods have been used: the mean f ree path method and the method of direct statistical simulation. With the aid of the first method the location of the condensation zone with in a porous body is determined as a function of the evaporating surfac e-to-porous layer temperature difference and also of the condensation coefficient. The second method is employed in a one-dimensional case t o obtain (without condensation) the density, velocity and temperature distributions for a gas in a porous layer and in a gas medium behind t he porous body. It is shown that the agreement between the parameters obtained by both methods for the gas flow escaping the porous layer is quite satisfactory.