Research On The Key Technology Of Plasma Anemometer Based On Glow Discharge

As an important role to play in the future development of flow measurement, research based on air discharge plasma flow measurement system is urgent to be carried out. Compared to other air discharge regions, the volt-ampere characteristics of glow discharge is more suitable for the requirements of flow measurement. So the main work of this paper is to realize argon glow-discharge by using COMSOL Multiphysics, then coupling gas flow, to observe the response of discharge model on the varied flow velocity. Because plasma involves a variety of physical phenomena, and the model is complex and highly nonlinear, it is difficult to achieve results perfect reappearance. However, it has certain guiding significance for future experiment if we can get the relationship between flow velocity and the electrical signal value with considering various major parameters.To simulate DC glow discharge plasma and RF glow discharge plasma respectively by using COMSOL Multiphysics. Choosing fluid model, mesh and numerical solution are realized by COMSOL Multiphysics. Observing the simulation results, especially the electron density, electron temperature, current, potential and electric field intensity, compare them with the actual results to verify the stability and accuracy of the model. Comparing DC glow discharge and RF glow discharge, to choose a suitable discharge mode for flow measurement.Discharge will be influenced by different discharge device geometry structure and initial parameters. To compare the electron density distribution under different electrode spacing and drive power frequency. This work will provide the foundation for optimizing discharge device and parameters.Based on the RF glow discharge has been established, to explore the interaction mechanism between gas flow and discharge plasma. The flow state can be classified as laminar flow and turbulent flow. The situation of turbulent is more complex, so laminar gas flow is used in this paper. Coupling gas flow and RF glow discharge plasma model, obtain electrical signal values corresponding to different flow velocity, and fit relationship curve between flow velocity and electric current. On this basis, observe influence on the measurement results through changing the electrode spacing and driving power frequency respectively.