CFD investigation of cooling of a heated cylinder placed on a flat surface

Abstract

A numerical study was conducted on a hot cylinder held on a levelled surface and cooled using a rectangular jet of air in order to appreciate the outflow and the subsequent heat transfer. The above study has been carried out numerically for determining the flow of air along with the transfer of thermal energy from the hot surface of the cylinder. The cylinder’s surface was controlled in hot conditions using a constant supply of electrical power. The flow of air was varied using the Reynolds no., ReD, ranging from 2 × 104 to 8 × 104. The span of the dimensionless distance between slot jet outlet and cylinder (z/b) was varied between 2 and 10. The dimensionless ratio of rectangular jet width to cylinder diameter, b/D, was equal to 0.1. The distributions of the Nusselt no. at various points on the surface of the heated cylinder obtained from numerical studies have been reported in the present work. It was observed that the maximum cooling of the cylinder occurs at the stagnation point. Out of all the different turbulence models used in the present investigation, the RNG k-ε turbulence model and Realizable k-ε give better results.