Pulsed jet control of a short diffuser

This experimental study investigates the control of flow in a short diffuse r with a 2 x 45 degrees divergence angle, using wall synthetic jets. Measur ements are made by particle image velocimetry. Velocity profiles, velocity fields, and Vorticity maps show that the flow, initially separated as a fre e jet, undergoes a global excitation which creates periodic oscillating str uctures producing large fluid motions in the vicinity of the wall. This res ults in an increased mixing of the primary separated jet with the surroundi ng fluid. (C) 2000 Academie des sciences/Editions scientifiques et medicale s Elsevier SAS.