Experimental investigation of heat and fluid flow in an actuated impinging jet flow

Abstract

The objective of this work is to how the surface heat transfer and flow characteristics can be affected by jet flow by excitation of which changes the turbulence characteristics of the flow. Main body of this work is experimental analysis; nevertheless some simple numerical analysis is also presented in order to make some comparisons. The hot-wire measurements and flow visualizations are performed. As a flow actuator a loudspeaker is used once the piezo-electric benders were found to be unsuccessful. Acoustic (pressure) wave generated by the loudspeaker travels along the flow system and reaches the jet nozzle where it generates an oscillating component on the mean nozzle velocity. Parameters used on this study are shortly Re.10000, dimensionless jet to plate distance is equal to 6, as a non-dimensional excitation frequency Strouhal number is changed in the range of 0.St.1, and as for the excitation amplitude, voltages sent to the 20X amplifier are 0.5V, 1.0V and 1.5V.