Simulating plasma actuators in a channel flow configuration by utilizing the modified Suzen-Huang model

Abstract

Objective: The present investigation is an attempt to simulate a channel flow driven by two plasma actuators placed on top of each other.

Methodology: The model utilizes a modified form of the Suzen-Huang plasma actuator which accounts for a 'dielectric shielding' boundary condition for the potential governing the electric field. In addition, the Fokker-Planck (drift-diffusion) characteristics were implemented on the potential governing the surface charge density.

Results: The model is able to correctly predict the maximum velocities for channel flow at larger channel heights. However, at lower channel heights, the model underestimates the maximum velocities.

Analysis and Discussion: An analysis of the body force profile at the centreline region in the vicinity of the plasma actuators indicated that negative vertical body forces may have contributed to the discrepancies. Following this observation, a hypothetical model which does not account for vertical body force contributions on the fluid domain was simulated. While the results from this hypothetical model show marginally improvements to the maximum induced velocities at larger channel heights in relation to experimental data, the model still underpredicts the velocity magnitude at lower channel heights. This could point to the presence of interactions between the induced body force of the top and bottom actuators, specifically at lower channel heights, that have not been captured in the present model.