Study Of Synthetic Jet Actuator Design

Synthetic jet is well known as a novel method of active flow control. The core of technique is synthetic jet actuator. It is of three advantages such as: no gas source and mass injecting, simple structure, and compatible for integrated fabrication. The further progress of synthetic jet is dependent on the design of actuators which have influence on promising applications such as: separation control, boundary control and mixing strengthening.The design of synthetic jet actuator and characteristic of flow field are studied by the method combined experiment and numerical simulation, and flow control on airfoil is investigated experimentally. The work of paper includes mainly four parts as follow: (1) The flow field of 2-D synthetic jet is simulated; (2) The synthetic jet actuator and control circuit are designed; (3) The velocity of the synthetic jet flow field is measured; (4) The control of flow on YLSG107 airfoil using synthetic jet actuator is investigated experimentally.By adopting the 2-D unsteady ,incompressible Reynolds Averaged Navier-Stokes (RANS) equations, the flow field of synthetic jet is simulated. The results clearly reveal the features of synthetic jet and the process of vortex pairs' formation, advection ,diffusion and entrainment effect on ambient fluid. The effects of boundary condition at the orifice and actuation frequency on jet flow field are numerical investigated. The information of the flow field is obtained.The designed actuator is driven by electromagnet force. Which is machined by precise instrument. The designed power amplifier circuit is used to increase the energy of actuator. The measurement of velocity of the jet flow field is carried out with the TSI-IFA300 constant temperature anemometer. The velocity profile and the center line velocity of jet flow field in three different actuation signals(triangular wave, sinusoidal wave and square wave) and different actuation frequencies are studied experimentally. It is shown that the square wave has the best actuation result and the triangular wave has the worst one. A full developed, two-dimensional jet is formed by the slot. The two resonance frequencies are 475Hz and 1700Hz .When the actuator is actuated with a square wave, the corresponding mean velocities are 4.70m/s and 4.22m/s. At last, the experiment using synthetic jet to fulfill the airfoil flow control is performed. The results show that stalling characteristic is improved,and problems in experiment are discussed.