Natural convection in a rectangular cavity heated from below and cooled from top as well as the sides

A three-dimensional, numerical simulation of Rayleigh-Benard convection in a cavity, having aspect ratios A(x)=4 and A(y)=4 has been performed using m ultigrid method, for Ra less than or equal to 1x10(4). The effect of the th ermal boundary conditions of the vertical side walls on the flow bifurcatio ns has been investigated by considering isothermal and conducting side wall cases. It has been found that the steady state flow patterns and the criti cal Rayleigh numbers for transition from one pattern to the other are compl etely different for each of the above mentioned boundary conditions. The lo cal heat transfer distributions at the bottom and top plates are obtained a nd variations of the average Nusselt number for the isothermal and conducti ng side wall boundary conditions are compared for the range of Rayleigh num bers investigated. (C) 2000 American Institute of Physics. [S1070-6631(00)0 1201-0].