Comparative CFD Study of Heat Transfer Characteristics in Top and Bottom Jet Impingement Cooling

Jet impingement heat transfer was studied using top and bottom surface stationary cooling configuration. Using rectangular steel plates of 230mm by 120mm by 12mm, and single jet diameters of 10mm and 40mm with impingement gaps of 115mm and 155mm. Experimental data were reduced by lumped thermal mass analysis model for calculating convective heat transfer coefficient and ANSYS CFD software was used to validate experimental results. The results analyzed by lumped thermal mass analytical showed that, for a diameter 10mm and impingement gap of 115mm, the Top surface showed bettercontrolled cooling with a 63% difference, and at impingement gap, 155mm top surface maintained better cooling with a 66% difference for a diameter 40mm. The calculated convective heat transfer coefficient increases with an increase in pipe diameter and a corresponding increase in impingement gaps in both cooling processes. The CFD results revealed maximum heat fluxes of 22518W/m2 and 6742.8w/m2 for the top at 10mm and 40mm diameters. This proved top surface cooling configuration is better than the bottom with maximum heat flux. The validation showed an acceptable error margin for both surfaces with a diameter of 10mm 0.2s/0C for the top surface.