An Experimental Study of Entrainment Effects on the Heat Transfer From a Flat Surface to a Heated Circular Impinging Jet

This paper reports on a study to investigate the effect of ambient air entrainment into a heated impinging jet on the heat transfer from a flat surface. It provides a well-characterized jet by using a long circular pipe to obtain fully developed pipe flow for the jet and a uniform heat flux surface thermal boundary condition by electrically heating a vacuum-deposited gold coating. The surface temperature distribution is measured using a liquid crystal.