Passive cooling of conducting and insulating heat generating cylinders in enclosures with openings

The objective of this paper is to study cooling by induced convection of a vertical cylinder in an enclosed space with openings. The enclosed space has various configurations: it is either horizontal only, or combined vertical-horizontal, but its width remains constant. The study in general aims at finding the preferable configuration in which the maximum and mean temperature of the cylinder would be the lowest, and to compare the results for conducting and insulating cylinders, made either of stainless steel or cement. A laboratory-scale model is studied both experimentally and numerically. Each cylinder is 50mm in diameter and 100 mm high. It is heated from inside by a cartridge heater, installed in a drill along the cylinder axis and connected to an external power source. Temperature measurements are performed at various locations inside the cylinders by fine thermocouples using a multi-channel data acquisition unit. Numerical simulations are performed for the velocity and temperature fields in the enclosure, using the Fluent 5.5 software, accounting for both convection and radiation. The cylinders are modeled as they were built in reality: they had a heat-generating core and conducting body. Comparison of the experimental results with the numerical predictions is presented and discussed.