The Investigation On Flow And Discharge Characteristics Of The Low Temperature Plasma Jet

Cold atmospheric pressure plasma jet is a research hotpot of plasma technology in recent years, which can be generated in atmosphere and has low temperature, low cost and high concentrations of active particles. There are broad application prospects in various fields, such as environmental engineering, material modification and biomedical engineering, which cause extensive concerns. However, the interactions and the reactive specises improvement still need to be investigated deeply. In this paper, Ar is chosen as the main working gas, the flow and discharge characteristics are studied in both numerical simulation and experiment.Firstly, a simulation model based on discharge and fluid model is established by Comsol and Fluent to study the influence of electrodes’structures on initial electric field, velocity distribution and mole distribution of Ar in laminar and turbulent flow respectively, and the influence of distance between array elements. The results show that the position and length of the electrode have great influence on the initial electric field. The increase of flow rate is conducive to the forward propagation of the jet in the laminar state, the flow in turbulent state leads to shorter length of jet. The existence of needle electrode in jet makes the velocity and molar distribution in central axis lower. With the increase of the distance among the jet elements, the interactions of plasma coloumns decrease.Secondly, stable Ar plasma jet is generated base on sinusoidal excitation and the dielectric barrier discharge in the atmospheric environment, and little H2O and O2 is mixed, various optical and electrical detective techniques are used to study and compare the fundamental features of jet, such as length, temperature and spectrum. Futhermore, one-dimensional and two-dimensional plasma jet array are established. The results show that in the mixture of H2O in Ar, the initial discharge voltage decreases, the jet length increases, the temperature decreases, and the intensity of spectrum decreases obviously. When mixing O2 in Ar, a mixture of 0.5% O2 and Ar promotes the jet forward, which makes the jet length increase slightly. A mixture of 1%O2 and Ar makes the jet length random, and the temperature obviously decreases. The addition of O2 makes the intensity of OH (309nm) spectral line decrease obviously. In this paper, one-dimensional and two-dimensional plasma jet array are established which can generate stable plasma jet.