High-Speed Aerodynamic Flow Control using Nanosecond Repetitively Pulsed (NRP) Plasmas

Nearly all high-speed flight vehicles are plagued by significant aerodynamic challenges posed by high-speed turbulent boundary layers and shock wave-boundary layer interaction (SWBLI).  Such aerodynamic challenges must be addressed for efficient and accessible supersonic/hypersonic flight and economical access to space. One potential solution is plasma-based flow control.  The ability of surface plasma to effect low-speed aerodynamic flows has been well-established, and recent work has demonstrated significant promise for high-speed compressible flow control using pulsed filamentary plasma discharges. Plasma actuators have many advantages: no moving parts, active control at frequencies up to >100 kHz with very fast time response, and flush integration with surfaces. In addition, when compared to more traditional DC or AC-driven plasmas, using ultra-short duration (~10-100 ns) pulses at high frequencies can significantly reduce the required power budget. Interest in such nanosecond repetitively pulsed (NRP) plasmas for flow and combustion control has increased significantly in the past decade, and several recent studies have demonstrated control authority of high-speed, compressible flows using NRP plasma-based actuators. This presentation will provide a brief introduction to NRP plasmas and review recent work on using such plasmas as actuators for high-speed aerodynamic flow control.  Critical knowledge gaps and directions for future research will also be discussed.