Shear Flow Control Using Synthetic Jet Fluidic Actuator Technology

Abstract : This research outlined in this report focuses on a novel approach to manipulation and control of shear flows using surface fluidic actuators based on synthetic jet technology. Synthetic jets are zero-mass-flux in nature and are synthesized from the working fluid in the flow system in which they are embedded. Although there is no net mass injection, the jets enable momentum transfer into the flow system to be controlled. Thus the interaction of a synthetic jet with an embedding flow near the flow surface results in formation of closed recirculating regions and in an apparent modification of the surface shape. These attributes enable synthetic-jet control systems to effect significant global modification of embedding flows on scales that are one to two orders of magnitude larger than the characteristic length scale of the jets. While conventional excitation methods have been limited to frequency bands tailored to the linear receptivity mechanisms of a given flow, fluidic actuation facilitates exploitation of nonlinear mechanisms for amplification of disturbances in a very broad frequency band. The present report discusses the flow physics of synthetic jets and the application of fluidic technology based on synthetic jets for dynamic control of jet vectoring and the modification of the aerodynamic performance of lifting surfaces.