Pulsed jet control of a short diffuser

This experimental study investigates the control of flow in a short diffuser with a 2 x 45 degrees divergence angle, using wall synthetic jets. Measurements are made by particle image velocimetry. Velocity profiles, velocity fields, and Vorticity maps show that the flow, initially separated as a free jet, undergoes a global excitation which creates periodic oscillating structures producing large fluid motions in the vicinity of the wall. This results in an increased mixing of the primary separated jet with the surrounding fluid. (C) 2000 Academie des sciences/Editions scientifiques et medicales Elsevier SAS.