Flow Characteristics of a Plane Jets with Deflectors inside the Nozzle

Abstract

The present paper describes the flow characteristics of a plane air jet with deflectors. The divergent or convergent deflector was installed symmetrically inside of the plane nozzle. The effects of the angle and the length of deflectors on the mean and fluctuating velocities, and the velocity ratio of the inner jet to outer jet at the nozzle exit were examined by the hot-wire measurement and the flow visualization. In the case of the jets with the divergent deflector, the outer jet was accelerated and the inner jet was decelerated. The spreads of jet with the divergent deflector increased in the near field of the jet. In the case of the jets with convergent deflectors, the outer jet was decelerated and the inner jet was accelerated. The spreads of plane jet with the convergent deflector was smaller than the other jet. The relation between the velocity ratio of the nozzle exit, the area ratio, the pressure drop, the spreading rate and the virtual origin of a plane jet with divergent or convergent deflectors was found.