Characteristics Of Surface Dielectric Barrier Discharge And Its Propulsive Force

Surface dielectric barrier discharge(SDBD)is a popular discharge to produce low temperature plasma,with electrodes setting on both sides of dielectric slab and discharge occurring along the barrier surface.It can generate large areas of plasma on the barrier surface and transfer electrical energy to the air kinetic energy and hence produce electrical propulsive force.It can be used in fields of aerodynamics and aerospace.In this thesis,we study experimentally the electrical characteristics and electrical propulsive force of SDBD under different structures.The effect of the applied voltage,gas pressure,width of two electrodes and separation on the discharge and propulsive features are tested.The results show that the pulsed current waveform of SDBD is asymmetrical in positive and negative half cycles,with the current being larger,narrower and multiple in pulses in positive half cycle.The amplitude of the current in negative half cycle is small and it appears as a single pulse.The current amplitudes in both positive and negative half cycles increase with the applied voltage.The breakdown and sustaining voltages increase as the width of exposed or insulated electrode,the separation and the gas pressure increasing.One can improve the propulsive force and efficiency by increasing the voltage and the pressure,or reducing the electrode separation and width.For surface corona discharge,its electrical characteristics are similar with SDBD,but the pulsed current waveform in negative half cycles is larger.The dimension of surface corona electrode is small and as a result it avoids the “push-pull” effect.So efficiency of surface corona discharge is higher and it is more suitable for thruster.