AN EXPERIMENTAL STUDY OF HEAT TRANSFER BY JET IMPINGEMENT ON ROUGHENED SURFACE WITH INITIAL CROSSFLOW

Impingement heat transfer from the rib roughened surface with two-dimensional arrays of circular jet has been investigated in comparison to the jet orifice plate.The study covered jet at Re_j=5000-20000;the initial crossflow rate G_c/G_j =0-1.3;and nondimensional jet-to-surface spacing Z_n=1.5,2,2.5,3.The experimental results show that the impingement heat transfer from the rib roughened surface will be improved by increasing the initial crossflow rate.The heat transfer characteristics are considerably affected by the jet-to-surfaces spacing,and there exists an optimum.The effect of relative position of jet hole to ribs on heat transfer has been observed.