空气放电等离子体中活性粒子数浓度演化规律分析

Evolution Law Analysis of Active Particles Density in Air Discharges Plasma

为获得空气放电等离子体中活性粒子的演化规律,耦合了组分浓度方程和能量传递方程以及Boltzmann方程,建立了空气放电等离子体动力学模型,对空气中单次和重复放电进行了数值计算,分析了空气放电等离子体中活性粒子数浓度随电子数浓度和约化场强以及放电频率的变化趋势。结果表明,放电等离子体中的活性粒子数浓度随电子数浓度的增加而大幅增加,当电子数浓度为1.0×104cm-3时,放电产生的O原子粒子数浓度最大值约5.0×107cm-3,而当电子数浓度增加到1.0×108和1.0×1012cm-3时,O原子粒子数浓度的最大值则相应地提高到5.0×1011cm-3和5.0×1014cm-3;约化场强的提高,获得的活性粒子数浓度增加;随着驱动电压频率的增加,氧原子O的周期变化达到稳定所要经历的放电次数增加,O原子的粒子数浓度最大值随放电频率的增加而增加。

In order to get evolution law of plasma in air discharge, a kinetic model of air discharge plasma was created by coupling components number density equations, energy transfer equation, and Boltzmann equation. The model was used to calculated air single and repetitive discharges plasma, then regularity of active particles was analyzed with various electron number density , reduced electric field and discharge frequency. The results showed that, the active particles density increased with the rising of electron number density, the maximum number density of O atom is 5.0×10^7 cm 3 , 5.0× 10^11 cm^-3 and 5.0× 10^14cm^-3. When electron number density was respectively set at 1.0 × 10^4 cm, 1.0× 10 cm^-3 , and 1.0× 10^12 cm^-3 ; active particles density also increased with reduced electric field increasing. The maximum number density of O atom in repetitive discharges plasma increased when discharge frequency increasing , and it should take more time to achieve stability condition.