Using Computational Fluid Dynamics to Analyze Convection in Pin-to-Plane Plasma Discharge

Abstract

Abstract Multiphysics simulations were conducted to model the role of naturally induced convection in heat and mass transport within a non-isothermal plasma discharge chamber. A pin-to-plane discharge into chamber containing carbon dioxide can be used to possibly decompose carbon dioxide. The present study characterizes the role that convection plays in the diffusion of various products such as ions and excited-state species throughout the test chamber. Multiphysics software including computational fluid dynamics was employed in a two-dimensional transient simulation of a closed reactor with a large pin serving as the cathode and a bottom plate serving as the anode. The mesh was adjusted to best capture important discharge phenomena, while the simulated time was varied to best characterize the chemical processes.. Mesh validation was undertaken using the relevant minimum sizes required by the plasma, fluid flow, and heat transfer solvers. The flow induced by natural convection from the discharge was then compared to the flow induced by natural convection around a resistance heater operating with the same power input as the plasma. The results of this simulation are used to inform improvements on a parallel experimental system used to study the discharge, such as placement of gas concentration sensors and to better understand the heat and mass transfer through the discharge.