Heat transfer at the condensation of a gas-vapor mixture in an electric field

Abstract

The problems associated with the investigation of heat transfer processes at the condensation of vapor from a vapor-air mixture in the presence of an electric field have been considered. It is established that even very small additions of air impair vapor condensation and, hence, the heat transfer. It is shown that the application of an electric field to a vapor-air mixture can be an effective factor for eliminating the negative effects of the presence of air on the condensation process. It has been found out that a corona discharge specially created by means of notches on the surface of the inner electrode of a cylindrical system and its effects are the main reason for this. The experimental characteristics of the relative heat transfer coefficient at condensation as functions of the air concentration, the rate of the mixture’s delivery into the vapor condenser, and the specific heat flux at different electric field intensities have been obtained. The results are explained by the electric charging of the medium in the corona charge field, by the electric wind, and by the charging of the “vapor-liquid” interface. There has been derived a formula according to which the process of condensation is strongly influenced by the molecule effective diameter (ψ∼d ⁶_* ) increasing in the electric field due to the solvation of ions by water molecules resulting in a new mechanism for the intensification of the condensation process in an electric field.