Gas heating in plasma microcavities: surface effects

Abstract

Paper presented at the 8th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Mauritius, 11-13 July, 2011.Interest in microcavities containing plasmas is growing rapidly due to the number of high-technology applications: such as active flow control, spacecraft propulsion, controlled combustion and pollution control. The present paper discusses a self-consistent model for gas and charged and species dynamics in atmospheric microcavities. A self-consistent and timedependant model is described and applied with emphasis on terms involved in the close coupling among the fluid, the charged species and the electric field. The microplasmas are studied from an initial cloud until the stages of charged particle over-amplification and breakdown in small-spaces, where transients are particularly important. The importance of surface effects (namely secondary emission of charged particles from the electrodes) is compared in terms of spatial and temporal evolution of the plasma and fluid dynamics. Heating effects and gas depletion initiation are observed, highlighting the close interaction between neutral gas and charged species in governing the evolution of the microplasma.