Performance Evaluation of Porous Layer in Jet Impingement Heat Transfer

Abstract

AbstractJet impingement has been an important technique to increase the convection heat transfer between the solid and fluid. In turbine applications, jet impingement can be used to cool various sections of the engines such as the combustor case, turbine case/liner, combustor walls and the critical high-temperature turbine blades. This study investigates the improvement of cooling of the jet impingement when it is employed along with porous media. The numerical models are validated against the jet impingement on flat plates, with and without porous media. The presence of porous media changes the heat transfer characteristics of jet impingement. Hence, in the present work, parametric studies are carried out to investigate the effect of important parameters, such as porosity, Reynolds number and porous layer height on heat transfer characteristics of the flat plate. It is observed that by increase in Reynolds number, Nusselt number also increases. Porous medium decreases Nusselt number and homogenises the heat transfer. Porosity affects mostly on the stagnation Nusselt number, whilst porous layer height affects the distribution of Nusselt number on the flat plate.KeywordsPorosityNusselt numberPorous layer heightReynolds number