Rotation Effect on Jet Impingement Heat Transfer in Smooth Rectangular Channels With Four Heated Walls and Film Coolant Extraction

Abstract

The effect of orthogonal channel rotation on jet impingement cooling by arrays of circular jets in two channels was studied. Impinging jet flows on smooth target walls were in the direction of rotation in one channel and opposite to the direction of rotation in the other channel. Spent air exited the channels through extraction holes in each target wall which eliminates cross flow on other jets. Heat transfer results for these target walls, for the jet walls containing the jet producing orifices, and for the connecting sidewalls show as the jet rotation number increases to 0.0028, these wall Nusselt numbers decrease to 35, 25 and 30%, respectively, below the corresponding non-rotating values. Jet rotation number is a correlating parameter and as wall-to-jet temperature difference ratio increases to 0.129 the wall Nusselt numbers vary up to 10%. Comparisons are made with previous rotating results for target wall heating only and for the radially outward cross flow exit configuration.