Numerical Analysis of Natural Buoyancy-Induced Regimes in Isosceles Triangular Cavities

Abstract

This article deals with a numerical simulation of natural-convection flows using the control-volume finite-element method in isosceles triangular cavities, submitted to a uniform heat flux from below when inclined sides are maintained isothermal, without symmetry assumptions for the flow structure. The aim of the study is to examine a pitchfork bifurcation occurrence. The study provides useful information on the thermal exchange sensitivity to two governing parameters, the Rayleigh number and the tilt angle in a basin still receiving a uniform heat flux. Results show that the heated wall is not isothermal and the flow structure is sensitive to the cover tilt angle. Three regimes with two vortices or more, symmetrical or asymmetrical, can be observed. Results can be constructive for design enhancements in energy systems such as solar water distillers and air conditioning processes.

The first author acknowledges, with thanks, helpful and fruitful discussions with Dr. Jamel Orfi.