Investigation of natural convection via heatlines for Rayleigh-Benard heating in porous enclosures with a curved top and bottom walls

摘要

The current study deals with the heatline-based analysis of natural convection in porous cavities with the curved top and bottom walls involving the Rayleigh-Benard heating. The streamline cells are weak, and the wall-to-wall heatlines are observed for all the cases at the low Da(m) involving two test cases, Pr-m = 0.015 and 7.2. At the high Da(m), the convective force takes the command, and multiple heatline cells are observed for all the concave (except for high wall concavity) and convex cases. The directions of the streamlines (for all Da(m)) and heatlines (at the high Da(m)) are exactly opposite for the concave and convex cases. The case 3 (concave) is the efficient case based on the largest heat transfer rate for Pr-m = 0.015 involving all Da(m) and for Pr-m = 7.2 involving the low Da(m). At Pr-m = 7.2 and high Da(m), the case 1 (concave or convex) may be the efficient cases compared with the cases involving high wall curvatures.