Study on Control of Radial Attaching Jet Flow : 1st Report, Effects of Control Flow on Main Jet Flow Near a Nozzle

Abstract

An experimental study has been made of reattachment of a radial turbulent jet flow discharged from a cylindrical nozzle onto an adjacent offset disc plate. The effects of a step height (distance of nozzle center plane from the offset plate) and control flow rate (ratio of control flow to main jet flow, suction and blowing) on a flow pattern near the nozzle outlet section were investigated. Mean velocity and turbulent velocity distributions were measured with the aid of a hotwire anemometer. The velocity profile, shape and length of a jet potential core, and deflection of a jet center axis depend mainly on the combinations of the step height and control flow rate. An oil film flow visualizing technique was applied to determination of the flow pattern.