大气压空气针-水结构脉冲气-液放电特性研究

利用纳秒脉冲电源激励大气压空气中针-水结构气液放电，研究了不同脉冲参数下的放电特性、等离子体特性和活化水中活性粒子浓度的变化规律。结果表明，在一个脉冲周期内放电分为3个阶段，其中发生在脉冲持续时间内和下降沿的两次放电较强，上升沿的放电较弱。当脉冲电压增大时，放电电流、平均功率、发光强度和发射光谱强度均逐渐增大；当频率增大时，放电电流几乎不变，但是功率显著增大，放电发光强度和发射光谱强度均增大。电压上升沿时间的增大则会减弱放电强度，相应的放电发光强度和发射光谱强度均减弱。而电压下降沿的增大则会增强放电，发光强度和发射光谱强度增大。当脉冲电压、频率和下降沿时间增大，H2O2，${rm{NO}}_2^ - $和${rm{NO}}_3^ - $浓度逐渐增大；而电压上升沿时间增大会导致3种活性粒子浓度逐渐降低。

Research on the characteristics of atmospheric pressure air pulse gas-liquid discharge using a needle-water electrode

In this paper, a nanosecond pulse power supply is employed to excite the gas-liquid discharge in atmospheric air, and the discharge characteristics, plasma characteristics and the composition of activated water under different pulse parameters are studied. The results show that the discharge consists of three stages in one pulse period, among which the two discharges that occur during the pulse duration and the falling edge are stronger, and the discharge on the rising edge is weaker. When the pulse voltage increases, the discharge current, average power, luminous intensity and spectra intensity all gradually increase. When the frequency increases, the discharge current is almost unchanged, but the power increases significantly, the discharge luminous and spectra intensity also increase. The increase of the voltage rising edge time will weaken the discharge intensity, and the corresponding luminous intensity and spectra intensity will be weakened. The increase of the voltage falling edge enhances the discharge, and the luminous intensity and emission spectra intensity increase. When the pulse voltage, frequency and falling edge time increase, the concentration of H2O2, ${rm{NO}}_2^ - $ and ${rm{NO}}_3^ - $ gradually increases. The increase of the rising edge time results in the decrease of the three active species concentrations. These results are helpful to understand the mechanisms of gas-liquid discharge characteristics under different conditions, so as to control plasma and solution activity, which will promote further practical application of nanosecond pulse gas-liquid discharge.