Local heat transfer distribution of an impinging air jet through a crossflow

An experimental investigation is conducted to study the effect of crossflow on the local heat transfer distribution of a flat surface normally impinged by round air jet. The influence of jet-to-plate distances (z/d of 4, 6 and 12), the crossflow velocity to the jet velocity (M varying from 1/6 to 1/12) and the Reynolds number (Re varying from 6000 to 12,000) on the heat transfer distribution was studied. The local heat transfer characteristics are estimated using thermal images obtained by infrared thermal imaging technique. The center-line distribution of the Nusselt number along the length of the plate is provided and a correlation for the stagnation point Nusselt number varying with the experimental parameters was proposed. It is observed that the distance of the stagnation point from the geometric impingement point and its magnitude increase with the increase in M. This distance is seen to be higher for higher values of z/d.