交流和纳秒脉冲激励氦气中等离子体射流阵列放电特性比较

To obtain the stable atmospheric pressure low-temperature plasma jet with large scale and good uniformity, a one-dimensional plasma jet array discharge in He was generated excited by alternating-current (AC) and nanosecond (ns) pulse voltage. Discharge characteristics and parameters of the jet arrays were compared, including the uniformity, instantaneous power, averaged power and intensities of optical emission spectrum. The hydrodynamic and electrical interactions among jets were analyzed by capturing the Schlieren images of gas channels and estimating the effect of Coulomb force among jets. The results show that the jet array excited by ns-pulse voltage can improve the downstream uniformity, increase plasma plume length, instantaneous power and intensity of optical emission spectrum, and reduce averaged power consumption. Different from the case in AC excitation, the jet array excited by ns pulse voltage has nearly no divergence in the lateral plumes. The ns pulse power source can also reduce the effects of gas heating and Coulomb repulsion force, thereby suppressing the hydrodynamic and electrical interaction among jets, which is the main reason for improving the uniformity of downstream plume.