Natural convection from horizontal heated cylinder with and without horizontal confinement

Laminar natural convection flow around horizontal heated cylinder with and without confinement is numerically studied. Confinement is done above or below the cylinder at various vertical positions. Two-dimensional computational models using finite volume formulation have been developed and validated against experimental data. Local heat transfer predictions are correlated for an unconfined single cylinder. The significance of confinement on the top and bottom side of the cylinder is clearly demonstrated for a wide range of Ra  , and spacing between the cylinder and the confinement. In case of top confinement, the increase in NuθNuθ at the upper portion of the cylinder depends on the position of the wall. The confinement below the cylinder caused a reduction in Nu‾ at the bottom half of the cylinder as compared to the top half. For both cases, the effect of confinement can be neglected at high H/DH/D ratios.