大气压环环电极结构射流放电模型建立及仿真

The Model and Simulation Studies for Ring-Ring Electrode Structure Jet Discharge at Atmospheric Pressure

建立射流放电的仿真模型并对其进行研究,该工作对于深入研究其放电特性,进而在实际应用中优化射流放电等离子反应器设计具有重要意义。建立了大气压下环环电极结构射流放电系统,采用电压、电流波形和Lissajous图测量及发光图像拍摄等实验手段,研究了其放电特性。结合对实验结果和放电特性的分析,建立了一种环环电极结构射流放电的等效电气模型,将两电极之间的放电等效为DBD放电模型,将喷出管外的射流等效为可变阻抗,同时还考虑了溢流效应的影响,将其等效为可变阻抗,更真实准确地反映了射流放电的实际情况。基于此电气模型,进一步得到了放电等效电路,并利用Simulink建立了射流放电的动态仿真模型。仿真得到的电压、电流波形图和Lissajous图形与实验结果对比显示,二者是吻合的,验证了提出的等效电气模型的准确性。在此基础上,进一步仿真研究了电源频率和环环电极间距对电气特性及放电参量的影响,结果表明,放电功率和传输电荷都随电源频率的增加非线性地增大,随环环间距的增加非线性减小。还利用所建立的模型进一步得到了实验过程中无法直接测量获得的介质电压、气隙电压和放电电流等放电参量。

The model establishment for jet discharge and its simulation analysis are ot great interesting for studying the discharge characteristics as well as for optimizing the design of jet discharge plasma reactors in real applications. In this paper, the experimental system with the ring-ring electrode structure for atmospheric pressure plasma jet discharge is established, and the discharge characteristics are studied, by measuring voltage and current waveforms, Lissajous figures and lighting emission images. Based on the experimental results and discharge characteristics analysis, an equivalent electrical model for ring-ring electrode structure jet discharge is established, which can reflect the discharge. The discharge space between two electrodes is equivalent to a DBD discharge model, and the jet outside the tube is equivalent to variable impedance. The influence of spillover effect is also taken into account, and it is modeled as variable impedance. Based on the equivalent electrical model, an equivalent circuit diagram is deduced, and a dynamic simulation model is established in Simulink software. Voltage and current waveforms, and Lissajous figures can be well coherence withthe experimental results, which verify the proposed electrical model. The influences of the power supply frequency and ring-ring distance on the electrical characteristics and discharge parameters are also studied. Results show that the discharge power and transported charges both increase nonlinearly as the applied frequency increases, while both decrease as the ring-ring distance increases. The dynamic behaviors of discharge parameters that can not measured directly during the experiment, such as dielectric voltage, gas gap voltage and discharge current, are also obtained by the established model.