A comprehensive numerical model for the electrohydrodynamic flow generated by gas discharges and its application to simulate, design and optimize practical devices and processes

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Many processes in industry, medicine and environmental protection involve electrical discharges in gases. Ions generated in these discharges collide with neutral molecules, which results in the electrohydrodynamic gas flow. Designing and optimizing practical devices based on this flow require a thorough understanding of the process and ability to predict its electrical, chemical, thermal and aerodynamic characteristics. The long-term objective of the proposed research program is to create a comprehensive numerical algorithm, which can be used to simulate electric discharges and electrohydrodynamic gas flow, assuming different parameters of the process. This algorithm will be developed in phases, gradually increasing the complexity of the physical model. As not all applications need the numerical models in the full complexity, in parallel with the model development, the intermediate models will be used for simulation and optimization of some practical devices. Different versions of the developed numerical algorithm will first be validated on some generic configurations. At the same time, the fundamental properties of different kinds of electric discharge under various ambient conditions will be studied. Many aspects of the process are still not well understood, for example the role of some species and reactions. The results of numerical simulation will be compared with experimental data. After the accuracy of the numerical algorithm has been confirmed, it will be used to investigate some important practical applications. The electrohydrodynamic control of the flow boundary layer can potentially revolutionize the aerospace industry providing the most flexible, reliable and inexpensive control of lift and drag forces, and other flow parameters. The numerical models used so far by aerospace engineers are based on extremely simplified approaches, which use inadequate physics and need a detailed calibration. On the other side, the full discharge models proposed by the plasma physicists are impractical because they require very long computing time and large computer memory. A novel approach based on a mean discharge model, developed as a part of the proposed research program, should be able to compromise both approaches: it will include correct physics, but at the same time it could be used to solve many practical problems in a reasonable timeframe. It is also expected that the developed numerical algorithms could be used for designing and optimizing novel configurations of electrostatic precipitators. While these devices are routinely used in environmental protection, new challenges arise from stricter air quality regulations. The main research activities in this area are focused on collection of submicron particles. One of the new designs is based on Dielectric Barrier Discharge, but so far there have been no serious attempts to numerically simulate the process. The proposed program will attempt to fill this gap.