Synthetic Jet And Its Application In Active Flow Control

Flow control is a hot topic of the Aerospace Research, one of the topics at the forefront of today’sfluid mechanics research in the field. Flow control can be divided into passive control and activecontrol of the two categories, passive control easy to use, reliable performance, but when the actualsituation deviates from the design state, the control effect will deteriorate. Active control is injecteddirectly into the right in the flow field disturbance patterns and energy, make it with system flowoccurs some kind of interaction to achieve the control purpose, the control effect based on the actualworking conditions to achieve adaptive adjustment. Successful development and application ofadvanced active flow control technology, it may be pregnant with the birth of a new generation ofaircraft.Synthetic jet as a new active flow control technology, since no gas supply system, the structure issimple, fast response, the working frequency bandwidth and zero mass flow rate, etc., it has broadapplications in the field of flow control and fluid transfer. Actuator as the formation of an importantcomponent of the synthetic jet, how to its efficient design, for high control benefits to the smallenergy consumption, is the key of synthetic jet applied in active control.First, in this paper, thought design of efficient synthetic jet actuators research objectives,parameter optimization of conventional synthetic jet actuators, using particle image velocimetry-PIVcomprehensive analysis of the actuator operating parameters and the structural parameters on theperformance of jet. Developed a highly efficient fluid actuator can be used for boundary layer flowcontrol, get the structure of the flow field essential characteristics and physical model. And syntheticjet energy utilization efficiency is not high, proposed the concept of synthetic jet arrays, effectivelyimprove the energy efficiency of synthetic jet actuator.Secondly, based on the study of synthetic jet with the mainstream mechanism of unsteady, obtainan efficient fluid actuators for boundary layer separation flow control, proposed synthetic jet pulsestreamwise vortex unsteady flow control concept, obtain pulse streamwise vortex field structure andthe essential characteristics of its interaction with the mainstream boundary layer. And passive vortexgenerators and active pulse vortex generators on the boundary layer velocity profile of the controlcharacteristics are analyzed.Then, proposed the use of synthetic jet unsteady disturbances for S shaped inlet flow separationactive control strategies, designed and developed for high-speed flow control of single membrane dual chamber synthetic jet actuators. With traditional passive vortex generator and continuous jet activecontrol results were compared. The synthetic jet unsteady disturbance can effectively improve thetotal pressure recovery coefficient, reduce the flow distortion, for the research of S shaped inlet flowcontrol and practical engineering provides a effective way.Finally, the application of the synthetic jet in high angle of attack asymmetric vortices activeflow control are studied, Invented a kind of based on synthetic jet controllable high-frequencyunsteady small perturbation high angle of attack asymmetric vortex active control devices. Thiscontrol mechanism can achieve the direction of the random switching of the side force to be effectivecontrolled, so that it becomes conducive to high angle of attack flight control aerodynamic, and lightweight, high frequency disturbance, energy consumption is small, almost does not change the headshape of aircraft.