Numerical simulation of dynamic stall flow control using a multi-dielectric barrier discharge plasma actuation strategy

Abstract

To alleviate the deterioration in wind turbine performance caused by dynamic stall, the flow control of a pitching NACA0012 airfoil is investigated through numerical simulation of an alternating current dielectric barrier discharge (AC-DBD) plasma actuator at a Reynolds number Re = 135 000. To avoid the harmonic oscillations of aerodynamic force caused by unsteady DBD actuation, this work focuses on improving the control potential for steady actuation. The control mechanisms of actuators at various positions are investigated using five groups of actuators mounted at 0%, 3%, 10%, 45%, and 80% chord lengths c above the upper surface of an airfoil. The actuator at 80% c performs more efficiently in terms of lift enhancement in the initial upstroke and the final downstroke. The actuator at 0% c suppresses the growth of the leading-edge vortex and maintains the suction of the dynamic stall vortex (DSV). After the shedding of the DSV, it suppresses the secondary separation to delay the onset of dynamic stall. At the flow reattachment stage, the actuators at 3% c and 10% c accelerate the boundary layer reattachment by momentum injection. From these results, a multi-DBD control strategy is proposed. The scheme selects the optimal actuator in operation at a certain stage of dynamic stall and takes advantage of actuators at different positions to enhance the average and maximum aerodynamic force, delay the onset of dynamic stall, accelerate flow reattachment, and avoid excessive energy consumption.

Numerical Investigation on the Evolution Process of Different Vortex Structures and Distributed Blowing Control for Dynamic Stall Suppression of Rotor Airfoils

“…Due to the complexity and high cost of wind tunnel experiments on airfoil dynamic stall and the limitations imposed by the measurement equipment and technology, research has been typically confined to limited operating conditions. With the advancement in computational fluid dynamics, numerical simulation gradually became a crucial approach to studying the dynamic stall characteristics of airfoils [19][20][21][22][23][24][25]. Visbal and Garmann [26][27][28][29] studied the effect of sweep and unsweep on the dynamic stall of a pitching finite-aspect-ratio wing and undertook an analysis of the dynamic stall on a pitching airfoil using high-fidelity large-eddy simulations.…”

Flow Separation Control of Nacelle Inlets in Crosswinds by Dielectric Barrier Discharge Plasma Actuation

“…It has attracted wide attention in recent years and is widely used in biomedicine [12][13][14][15][16], environmental purification [17][18][19][20], catalytic technology [21][22][23][24], material handling [25][26][27], flow control, and other fields. Surface Dielectric Barrier Discharge (SDBD) [28] which has the advantages of easy adhesion, rapid response, and adjustable parameters, has been widely used in the fields of stall control [29][30][31][32][33][34], boundary layer rotation [35][36][37][38][39][40], lift enhancement [41][42][43], anti-icing [44][45][46][47][48] and other flow separation control applications. Surface dielectric barrier discharge is classified as Alternating Current Dielectric Barrier Discharge (AC-DBD), Microsecond Dielectric Barrier Discharge (µS-DBD), and Nanosecond Dielectric Barrier Discharge (NS-DBD), of which AC-DBD and NS-DBD are more widely used than µS-DBD.…”