Publisher : The Korean Society of Mechanical Engineers
DOI : 10.22634/KSME-B.19188.8.131.5281
Title & Authors
Dual Solutions for Steady Natural Convection of Air in Horizontal Cylindrical Annulus Yu, Ju-Sik;
Dual solutions for steady natural convection of air between two horizontal concentric cylinders are numerically investigated in the range of $D_i$/TEX>/L(=diameter of inner cylinder/gap width)10. It is found that, when the Rayleigh number based on the gap width exceeds a certain critical value, a new flow pattern forming two counter-rotating eddies in the half of the annulus can be realized, which is different from the crescent-shaped flow commonly observed. In the new flow pattern, the fluid near the top of the hot inner cylinder moves downward. This solution is found for D/L.geq.0.3, but not for$D_i$/TEX>/L0.2. As $D_i$/TEX>/L increase, the critical Rayleigh number is decreased, and tends to a finite limit.t.