Numerical Investigation of Buoyancy-driven Flow in a Crescentshaped Enclosure

The buoyancy-driven flow in a crescent cavity is numerically analyzed by employing the finite volume method for the first time. The enclosure was filled with an incompressible fluid, whose thermal properties are given by Pr. The enclosure's left and right arcs have different temperatures. Two cases are adopted in the present work; in the first case, the left and right arcs were considered cold and hot. While for the second case, the thermal boundary conditions of the arcs were shifted. The results were illustrated for Prandtl number 0.71 ≤ Pr ≤ 50 blockage ratio of the space 0.1 ≤ B ≤ 0.5 and Rayleigh number 103 ≤ Ra ≤ 105. For both considered cases, the velocity profiles increased with the increasing Ra and decreasing B. While the increase in Ra increases the values of Nu for both arcs. Also, the flow and thermal pattern are not affected by changing the fluid's thermal properties represented by Pr. Furthermore, when the influence of buoyant force is substantial, and the cavity width is wide, the shifting thermal boundary conditions become evident.