Abstract
An underexpanded jet is utilized in industries to cool a heated material, to blow the dust away from the product and so on. When the jet impinges on such objects, the jet oscillates and a noise radiates from it. Thus, it is necessary that flow patterns of the jet at impingement, which greatly affect those efficiency, is analyzed in detail. In this paper, the underexpanded jet impinges normally on a thin plate. Behaviour of the jet is expected by analyzing a vibration of the plate at different nozzle-plate spacings. As a result, one of the jet flow patterns, a lateral oscillation mode, was observed and the oscillation plane of the jet was found to rotate.
