Synthetic Jet And The Discussion Of Its Application In Active Flow Control

As a new active flow control technique, synthetic jet has attracted more researchers'attention in recent years. And now it is becoming one of the most promising international research fields. By experimental measurements and numerical simulation, the effects of geometry and stimulation parameters to the synthetic jet, as well as the feasibility to apply synthetic jet to supersonic flow control are shown in the thesis.The PIV system supplemented by phase-locked circuit is used in the experiment. Through the experimental results of both instantaneous and average flow, the differences between synthetic jet and conventional jet is proposed. In this thesis, more attention was paid to compare the characteristics of different flow fields when the parameters, such as: frequency, input energy, orifice depth, orifice diameter and orifice shape, were changed, which will be helpful to the design and optimization of the synthetic jet actuator. After the study of the jet produced by single orifice, the effect of the distance between orifices on the process of syncretizing and development of parallel dual synthetic jets was studied. Finally, the parallel synthetic jet arrays with more orifices are measured and contrasted with the single orifice in the thesis.In order to improve the performance of the SERN (Single expanded Ramp Nozzle) under the over-expanded condition, numerical simulation was performed with FLUENT software combined with UDF (User Defined Function). The compares of separation areas, thrust and lift were made when the different stimulation values, synthetic jet angles, stimulation positions and the actuator volumes were applied to the numerical simulation. According to the numerical simulation results, the synthetic jet could achieve the augmentation about 1.8% for the thrust and 3% for the lift in one period, when the actuator volume is the second condition and the stimulation value is 20m/s.