Features of a laminar flow of volatile binary gas mixtures in plane and coaxial channels

Abstract

When a laminar flow of binary gas mixture passes through a plane (Fig. 1) or coaxial (Fig. 2) channel, in which recondensation of the volatile component of the binary gas mixture occurs, the established distributions of mass velocity and pressure in the channel will differ from the velocity and pressure distributions in a gas flow undisturbed by recondensation. A theoretical investigation of flows complicated by recondensafion is of interest for practical calculations of heat exchangers, condensers, etc. [ 1 ]. In view of this the present investigation was devoted to a study of established laminary isothermal flows of a binary gas mixture in plane and coaxial channels with due consideration of recondensation of molecules of one of the gas mixture components. The analytical investigations of flows in a channel between coaxial cylindrical surfaces and between two parallel plates are similar and, hence, we will dwell in more detail on the analysis of flow in a coaxial channel. On one of the surfaces forming the channel absorption of molecules of the first component of the gas, mixture occurs, and on the other surface release (e.g., condensation and evaporation) takes place. We will assume that the relative concentrations c a of the first component at the surface of the inner cylinder c H and at the surface of the outer cylinder c12 are kept constant