Laminar axisymmetric multicomponent buoyant plumes in a thermally stratified medium

Abstract

This paper presents the results of a numerical study of laminar axisymmetric plumes that emanate from a source of combined buoyancy due to simultaneous heat and mass diffusion. The ambient is considered to be stably stratified through a linear temperature increase with height. Boundary layer and Boussinesq approximations are incorporated in the governing equations of mass, momentum, energy and species conservation. These equations are solved using an explicit finite-difference numerical scheme. Velocity, temperature and concentration fields are obtained for a range of Pr and Sc. The basic physical mechanisms that underlie these flows are described. The results indicate a complex interaction between buoyancy ratio, thermal stratification, and Prandtl and Schmidt numbers.