Impact of air flow on streamer discharges from a 3D fluid model

Abstract:

In this presentation, we show simulation results of streamer discharges in unsteady air flow from a 3D fluid model we developed. The model couples the drift-diffusion equations for the charged particles, the Navier-Stokes equations for the air and the Poisson equation for the electric field.

By using an implicit time integration scheme and an unstructured mesh with adaptive refinement, the model is designed to study electrical discharges and the effects of unsteady airflow at different timescales defined by electrons, ions and neutrals and to simulate long duration discharges around solid bodies of complex geometry.

The accuracy of the model has been verified by comparing its simulation results in steady air with five different streamer codes on a test case from the literature. Our results are consistent and among the most accurate.

We present simulation results from a series of successive long duration positive discharges in a transverse airflow condition in which each of positive streamers are initiated at the electrode, propagated, and subsequently come to a full stagnation.

The results show that the impact of a low speed air flow on streamers comes essentially from the ions being blown away by the wind.