FLOW TRANSITIONS AND PATTERN SELECTION OF THE RAYLEIGH-BENARD PROBLEMIN RECTANGULAR ENCLOSURES

In this paper, research efforts in the broad area of flow transitions of Rayleigh-Benard convection in rectangular enclosures with sidewalls are reviewed. Numerical studies are given primary emphasis. However, experimental works that are relevant are described. Our current physic al understanding of the transition phenomena as occurring in the Rayle igh-Benard problem is critically reviewed. Two broad categories of tra nsition are discussed. In the former, the transitions are temporal in nature, and mostly confined to small enclosures. In the latter, transi tions are a result of change in spatial patterns. This phenomenon, kno wn as pattern selection, is looked into for-both small and intermediat e enclosures.