| Dielectric barrier discharge plasma with staggered electrodes flow control can be used as a technical means to perturbation the airflow nearby with the purpose of improving aerodynamic characteristics of the power unit and is significant to elevate aerodynamic performance of aerial vehicle. Now, plasma flow control has become a focus of international aerodynamics fields for its potential extensive application foreground in drag reduction and lift increasing of aircrafts and stability extension and efficiency improving of aero engines.Recently, lots of researches concerning external separation flow control with the plasma have been carried out and rudimental application in internal flow control is formed gradually.In this dissertation diagnosis of the plasma effects, numerical simulations and mechanisms of plasma flow control are investigated firstly. Then blunt body flow control (external flow) using the plasma exciting is carried out followed by that of the compressor cascade flow control (internal flow). And finally, compressor stability range extension with the plasma actuation is investigated. In the external flow experiments, detailed flow field data such as velocity and turbulent intensity is obtained. In the internal flow experiments carried on the compressor cascades and the compressor, it is focus on the flow separation suppression, loss reduction and the stability range extension.The main research contents and results are as follows:Firstly, the schlieren interference method is used to capture interference fringes distortion introduced by the plasma and the density of the plasma is obtained through further calculation.Secondly, methods of plasma actuation intensification are investigated. Those methods include electrode layout modification, pressure reduction and gas injection.Thirdly, boundary layer characteristic modification by the plasma actuation is investigated through numerical simulation method.Fourthly, trace nitric oxide produced by the dielectric barrier discharge is detected directly by the planar laser induced fluorescence system. The experimental results demonstrate that the planar laser induced fluorescence system has many advantages in the research of plasma flow control.Fifthly, based on results of experiments and numerical simulation, mechanisms of plasma flow control are ascertained to be results of collisions, temperature increasing and chemical reactions. Sixthly, results of flow field measurement by laser Doppler velocimetry show that plasma actuation can modify the flow field near the electrodes and play the roles of boundary layer acceleration and vorticity deduction.Seventhly, two dimensional particle image velocimetry system is used to investigate the plasma actuation on the flow field in the wake of a circular cylinder and a hump model cross flow. Analysis of transient and time averaged flow field showed that plasma actuators placed in the surface of the circular cylinder changed the flow field in circular cylinder cross flow control by forming a jet at the wake.Eighthly, separation suppression and loss reduction in the compressor cascades with plasma actuation on the suction side are investigated by tri-hole probe and hot wire anemometer. Three-dimensional flow fields at the exit of a compressor cascade with plasma actuation on the tip wall are measured with a mini five-hole pressure probe. Experimental results show that the plasma actuation is effective in flow loss reduction and the plasma actuation is also effective in suppression flow separation when coming velocity is low.And finally, using plasma actuation to extend low-speed axial compressor stability range is investigated experimentally. The effect of plasma actuation on low-speed axial compressor's pressure coefficient and flow coefficient near stall is studied. The effects of plasma actuation strength and location on flow control effect are also investigated. Compressor mass flow coefficient near stall decreased by 5.07% with plasma actuation at the rotor speed of 1080 r/min.
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