Low-Reynolds Number Flow Control Using Dielectric Barrier Discharge-Based Actuators

Abstract

Dielectric Barrier Discharges (DBD), operated at KHz and KV range, can create athermal plasma via collision processes and induce near wall jet. In this paper, we investigate the potential of using DBD to conduct flow control at low Reynolds numbers, motivated by micro air vehicle (MAV) applications. A previously developed computational methodology, based on the e N transition model and the k-turbulence closure is adopted. The effects of actuators on the flow fields are represented with a body force model in the momentum equations. The flow control over an airfoil SD7003 at the chord Reynolds number of 6×10 4 is the focus of the present study. Specifically, we investigate both co-flow and counter-flow actuation strategies. The co-flow approach offers momentum enhancement via favorable pressure gradient in the near wall region while the counter flow approach can trigger earlier separation and transition by introducing adverse pressure gradients. The aerodynamic performance including lift and drag coefficients over a broad range of angle of attack (4 0-18 0) is studied, showing that improved lift and drag characteristics can be realized with DBD concepts for low Reynolds number aerodynamics.

Adaptive Flow Control of Low Reynolds Number Aerodynamics Using a Dielectric Barrier Discharge Actuator

“…This enables the simulation of complex flow fields at much smaller computational cost than first principle based models. This approach has been applied to the flow control in low Reynolds number airfoil 5,16 , lowpressure turbine 17 , yielding separation elimination or delay.…”

“…The DBD actuator model is a simplified model with linear electric field and constant net charge density 5,15 . As presented in Figure 2, this model prescribes localized body forces in a triangular plasma region bounded by two electrodes and dielectric surface.…”

“…Such vehicles are usually defined as having dimensions not exceeding 15 cm in any one direction and maximum flight speeds of 2 American Institute of Aeronautics and Astronautics around 10 m/s. As a consequence, these vehicles operate at Reynolds numbers of less than 10 5 . Due to the wind gust and the aircraft's light weight, the aerodynamics of MAVs is substantially influenced by the unsteadiness of the flight environment 1 .…”

Flow structures in flat plate boundary layer induced by pulsed plasma actuator

“…It is a simplified model based on experimental observations and empirical arguments, which adds a linear body force to the fluid. Of course, it is not perfect to handle the interaction of ionized particles of plasma with neutral gas, but it can capture the key features of plasma structure [19], such as momentum generation in higher pressure discharges, which can be assumed to be close to equilibrium plasma [22]. The main advantage of this model is computationally inexpensive, which makes it attractive for probing various new flow applications preliminarily.…”

Surrogate Modeling for Characterizing the Performance of Dielectric Barrier Discharge Plasma Actuator

“…It enables the simulation of complex flow fields at a much smaller computational cost. It has been applied to the flow control in low Reynolds number airfoil 24,25 , and low-pressure turbine 26 , and separation elimination/delay has been observed. The present effort using surrogate models assists in improving the earlier linear field/phenomenological approach.…”