Time and frequency domain investigation of the heat transfer to a synthetic air jet

Abstract

Heat transfer to a synthetic air jets is investigated experimentally. The influence of peaks in heat transfer outwith the stagnation region of the jet are of particular interest. Heat transfer to the jets is reported for experimental parameters, jet exit to impingement surface spacings, H/D = 1, Reynolds number of 3000, non-dimensional Stroke length, L0/D of 14.and an excitation frequency of 70 Hz Peaks in heat transfer outwith the stagnation region of the jet are investigated in both the time and frequency domain and a connection between the driving frequency of the jet and changes in the rate of heat transfer is outlined. It is shown that two type's changes in the rate of heat transfer outwith the stagnation region are present in synthetic jet impingement heat transfer; those associated with the jet excitation frequency and therefore attributed to interactions between the two jet flow regimes and those associated with the breakdown of coherent structures in the jet flow. © Published under licence by IOP Publishing Ltd.