Experimental evaluation of jet impingement cooling over flat surface with spent air exhaust ports on jet plate

Jet impingement is an effective means of localized heating or cooling. In many engineering and industrial applications, this process is used to get high heat flux. The present work deals with the studies of heat transfer characteristics of a single round impingement jet cooling on a flat surface with spent air exhaust ports on the jet plate. The experiments were performed to study the effect of the jet-to-target spacing and jet Reynolds number. The experiments were performed for jets of 3.4, 6, 9 and 12 mm diameter and jet to target spacing of 1, 2, 4, 6, 8 and 10 for optimum value. The Reynolds number varies from 2300 to 5600. The investigations reveal the non-uniformity of local Nusselt Number for an impingement jet. The distribution of local heat transfer on flat surfaces reveal the formation of secondary peaks from the stagnation point, which help in improving the overall convective heat transfer from the surface.