Unsteady Joule Heating Energy Model for Nanosecond Pulsed DBD Plasma Actuator

摘要

In this study, a model of nanosecond pulsed dielectric barrier discharge (NS-DBD) plasma actuator was developed for flow control analysis. Computational analysis of NS-DBD plasma actuator needs to solve Gauss's law for electric field, chemical species continuity equation for plasma including electron, positive ions, negative ions, neutral particles and Navier-Stokes equation for fluid. It leads to enormously computational cost due to time scale difference between plasma and fluid. For the efficient and accurate analysis, we developed unsteady joule heating energy model based on quasi-one-dimensional self-similar equation of NS-DBD plasma. The joule heating energy obtained from quasi-one-dimensional self-similar equation is applied to develop a model of dissipating unsteady energy source into fluid by plasma. This model reduced computational cost dramatically, and it is able to calculate various plasma parameters such as plasma propagation distance, electric field, electron density and joule heating energy. Also, this model can reflect the joule heating energy arisen from the physical phenomena of electrical current variations during a pulse period. The obtained unsteady energy source term was coupled with Navier-Stokes equation to analyze the flow disturbances made by NS-DBD actuator which produces propagating micro compression wave. The time-varying position of compression wave, the result of numerical analysis using developed model, is in agreement with the previously reported data from experimental and numerical analysis. The developed model was able to predict compression wave propagation due to NS-DBD plasma on various discharge condition.