Effect of Gas Flow on Atmospheric Pressure Microwave Plasma Torch

Atmospheric pressure plasma torch has a wide application prospect in the fields of chemical industry, environmental protection and degradation. The research of its device has attracted extensive attention from all walks of life. Based on the design of an atmospheric pressure microwave plasma reactor, the effect of gas flow field characteristics in the reaction tube on the plasma torch was studied in this paper. The experimental device uses a microwave source with a frequency of 2.45 GHz. The microwave generated by it is fed into the quartz reaction tube through the waveguide compression structure, so as to excite the argon in the tube to generate plasma at atmospheric pressure. The flow field in the reaction tube under different inlet modes was simulated by COMSOL simulation software, and the discharge characteristics under different flow fields are tested in the experiment. The simulation and experimental results show that although different inlet modes have a great influence on the convection field, the flow field can become stable after passing through a section of quartz tube, and the plasma discharge phenomenon is also similar. Therefore, the influence of flow field on plasma torch can be avoided by lengthening the quartz tube, thus reduce the difficulty of flow field design in microwave plasma torch.