Mechanism of compressor airfoil boundary layer flow control using nanosecond plasma actuation

• Published in: The International journal of heat and fluid flow 2019-12, Vol.80, p.108502, Article 108502
• Main Authors: Zhang, Haideng, Wu, Yun, Li, Yinghong
• Format: Article
• Language: English
• Subjects: boundary layer; Compressor airfoil; flow control; nanosecond plasma actuation
• ISSN: 0142-727X; 1879-2278
• DOI: 10.1016/j.ijheatfluidflow.2019.108502

•In this manuscript, the nanosecond plasma actuation is used to control the boundary layer flow of a typical CDA compressor airfoil.•The corresponding flow control mechanism has been uncovered using large eddy simulations.•It has been found that the nanosecond plasma actuation can influence the boundary layer flow through inducing two types of spanwise vortexes.•Especially, the plasma actuations located within the laminar boundary layer flow can act as a high-speed wall jet.•This finding further improves the ability of plasma actuation in controlling high-speed flows. The flow control effects of nanosecond plasma actuation on the boundary layer flow of a typical compressor controlled diffusion airfoil are investigated using large eddy simulation method. Three types of plasma actuation are designed to control the boundary layer flow, and two mechanisms of compressor airfoil boundary layer flow control using nanosecond plasma actuation have been found. The plasma actuations located within the laminar boundary layer flow can induce a small vortex structure through influencing on the density and pressure of the flow field. As the small vortex structure moves downstream along the blade surface with the main flow, it can suppress the turbulent flow mixing and reduce the total pressure loss. The flow control effect of the small vortex structure is summarized as wall jet effect. Differently, the plasma actuation located within the turbulent boundary layer flow can act on the shear layer flow and induce a large vortex structure. While moving downstream, this large vortex structure can suppress the turbulent flow mixing too.