Plasma Actuators for Landing Gear Noise Reduction

A primary component of airframe noise on both takeoff and landing approach is due to the landing gear. The inherent bluff body characteristics of the landing gear give rise to large-scale flow separation that results in noise production through unsteady wake flow and large-scale vortex instability and deformation. In this paper the use of single dielectric barrier discharge plasma actuator technology for landing gear noise control is explored. Proof-of-concept experiments that use plasma actuators to create an effective "plasma fairing" which minimizes flow separation over the gear are presented. Nomenclature D = cylinder diameter D Re = Reynolds number based on cylinder diameter D St = Strouhal number based on cylinder diameter ∞ U = free stream velocity * b f = body force (per unit volume) vector φ = electric potential D λ = Debye length 0 e = electrical permittivity of free space

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