Behavior of Air Jet Impinging on Curved Surfaces

Abstract

Impinging jets on the curves surfaces and flat plate are frequently used in industrial practice requiring studying the subatmospheric zone. It is important to understand the structure of behavior impinging jet on the flow fields. Same of prior researchers have concluded that a recirculation zone occurs on the impingement flat plate. This recirculation zone creates subatmospheric pressure at the impingement surface. This study has been made to investigate the effects of nozzle to plate spacing, the Reynolds number and changing of the surface shape on subatmospheric region which occurs on these impingement surfaces. The subatmospheric region could be very important in engineering application. It is hoped that this study will provide data for the further research on this subject. In the present study the air jets from convergent circular nozzle of 10-mm exit diameter have been allowed to impinge normally on a flat plate, hemispherical, and conical surfaces. Experiments were done with varying the stagnation pressure from 1.2 to 2 bars. Reynolds number based on the nozzle exit diameter for this range of stagnation pressure was changed from