BUOYANCY-DRIVEN INSTABILITY IN A VERTICAL CYLINDER - BINARY FLUIDS WITH SORET EFFECT .1. GENERAL-THEORY AND STATIONARY STABILITY RESULTS

Buoyancy‐driven instability of a monocomponent or binary fluid which is completely contained in a vertical circular cylinder is investigated, including the influence of the Soret effect for the binary mixture. The Boussinesq approximation is used, and the resulting linear stability problem is solved using Galerkin's technique. The analysis considers various types of fluid mixtures, ranging from gases to liquid metals, in cylinders with a variety of radius‐to‐height ratios. The flow structure is found to depend strongly on both the cylinder aspect ratio and the magnitude of the Soret effect. Comparisons are made with experiments and other theories, and the predicted stability limits are shown to agree closely with observations. Copyright © 1990 John Wiley & Sons, Ltd