1913 A Study on Oscillation of Supersonic Impinging Jets
Details
A supersonic jet issuing from a convergent nozzle impinges on a circular plate. The flow field between the nozzle and the plate is experimentally visualized and the vibration of the plate is measured using 8 strain gauges, which are radially glued to the plate, at different nozzle-to-plate spacings. The outputs of the strain gauges are analyzed using a FFT analyzer. It was found that the plate vibrates at certain natural frequencies and the vibration at each station has different phase differences. The behavior of the impinging jet is inferred from the pattern of the plate vibration, being compared to the structure of the impinging jet obtained from the visualized results in order to seek the causes. As a result, the jet is found to oscillate axisymmetrically at small nozzle plate spacing, while laterally at large spacing.
