Transient flow in a side-heated cavity at high Rayleigh number: a numerical study

Abstract

A series of two- and three-dimensional numerical simulations of transient flow in a side-heated cavity has been conducted. The motivation for the work has been to resolve discrepancies between a flow description based on scaling arguments and one based on laboratory experiments, and to provide a more detailed description of the approach to steady state. All simulations were for a Rayleigh number of 2 × 10⁹, and a water-filled cavity of aspect ratio 1. The simulations (beginning with an isothermal fluid at rest) generally agree with the results of the scaling arguments. In addition, the experimental observations are entirely accounted for by the position of the measurement instruments and the presence of an extremely weak, stabilizing temperature gradient in the vertical.