Experimental Study on the Characteristics of a Vibrating Elastic Plate Flow Generator

Flow characteristics by a Vibrating Elastic Plate Flow Generator (VEPFG) was investigated experimentally. The device was a plate made vibrated perpendicularly to itself at the leading edge. The flow was found to be generated for a narrow range of frequency around the resonance frequency, with its maximum at the resonance frequency. The induced flow rate and its efficiency were experimentally determined. The performances were relatively low compared with the analytically expected ones. The efficiency turned out to be of 10 per cent. On the basis of the visualized flow patterns, one of possible causes for the difference is attributed to the existence of unsteady large-scale discrete vortices at both the trailing edge and the side edges. The side-edge vortices are seen to reduce drastically the induced flow rate by the factor of more than two.