The impetus of this study is to investigate the effect of using multi dielectric-barrier-discharge plasma actuator (DBDPA) over the 3D-airfoil surface and improve the performance of it. Two designed DBDPAs are placed at the leading edge and a distance of x/c = 0.3 chord of the NACA 634-021 three dimensional (3D) airfoil. We solved the flow at different chord-based Reynolds numbers and in a wide range of angles of attack (AoA) (12∘ ≤ α ≤ 24∘), using a large eddy simulation (LES) turbulence model, which is implemented under the OpenFOAM package framework. Here, detailed flow mechanism analyses, i.e., three-dimensional vortical structure, separation phenomenon, lift and drag coefficients, variation fluctuations and spanwise flow, are investigated around the airfoil 3D. Massive flow separation and transient aerodynamic loads acting on the airfoil have been significantly suppressed by optimized flow control using the DBDPAs in the airfoil. Wavelet analysis with and without the presence of the plasma flow over an airfoil is reported. The spectral content of the induced plasma flow is analyzed using Fourier and continuous wavelet transformations. Also, the priority of using airfoil with multi-DBDPAs at pre-stall and post-stall AoA, especially about the force coefficient are analyzed precisely. Multi DBDPA modification for low Reynolds number on wings and blade turbines can increase efficiency and decrease the noise.
