Flow and heat transfer characteristics of a two-dimensional oblique wall attaching offset jet

Abstract Turbulent flow and heat transfer characteristics of a two-dimensional oblique wall attaching offset jet were experimentally investigated. The local Nusselt number distributions were measured using liquid crystal as a temperature sensor. The jet mean velocity, turbulent intensity and wall static pressure coefficient profiles were measured for the jet Reynolds number, Re = 53,200, the offset ratio ( H / D ) from 2.5 to 10, and the oblique angle, α from 0° to 40°. It is observed that the time-averaged reattachment point nearly coincides with the maximum Nusselt number point for all oblique angles, but the maximum pressure point does only for α =0°. The decay of the maximum jet velocity in the streamwise direction is found to obey the conventional −1/2 power law of the wall attaching offset jet for α ≤30°. The reattachment length and maximum pressure point are well correlated with offset ratio and oblique angle. The correlations between the maximum Nusselt number and Reynolds number for all oblique angles tested are presented.

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