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Numerical calculations of the 2-D steady incompressible driven cavity flow are presented. The NavierStokes equations in streamfunction and vorticity formulation are solved numerically using a fine uniform grid mesh of 601 × 601. The steady driven cavity solutions are computed for Re ≤ 21,000 with a maximum absolute residuals of the governing equations that(More)
In this paper, the results of flow-control experiments using single dielectric barrier discharge plasma actuators to controlflow separation andunsteady vortex shedding froma circular cylinder in crossfloware reported. Thiswork is motivated by the need to reduce landing gear noise for commercial transport aircraft via an effective streamlining created by the(More)
Single dielectric barrier discharge plasma actuators have been used to control flow separation in a large number of applications. An often used configuration involves spanwise-oriented asymmetric electrodes that are arranged to induce a tangential wall jet in the mean flow direction. For the best effect, the plasma actuator is placed just upstream of where(More)
Turbulent flow separation over a wall-mounted hump model and its control using plasma actuators were studied numerically and experimentally. The hump model chosen in this study was that used in a 2004 NASA Langley CFD validation workshop for turbulent separation control using synthetic jets. The numerical simulations solved the Reynoldsaveraged(More)
Plasma enhanced aerodynamics was used to provide roll control at high angles of attack on a scaled 1303 UAV configuration. The 1303 planform has a 47 degree leading-edge sweep angle. The flow over the a half-span model was documented with dye flow visualization in a water tunnel for a range of angles of attack. This revealed a complex flow structure that(More)
An experiment was conducted in a linear cascade of Pak-B blades for an exit Mach number of 0.3 to simulate the flow in the tip-gap region of a low pressure turbine blade row. The experiment focused on the independent effects of thickness-to-gap and gapto-chord ratios on the tip-gap flow behavior. Two extreme gap-to-chord ratios of 5% and 8% were chosen, for(More)
This work presents the study of the single-dielectric barrier discharge aerodynamic plasma actuator. To model the physics of the plasma discharge, a space-time lumpedelement circuit model was developed. The model solution compared well to some of the characteristic features of the discharge such as the dependence of the sweep velocity and maximum extent of(More)
Flow control to avoid or delay rotorcraft retreating blade stall can be an enabling technology for future high performance rotorcraft. Aerodynamic experiments and computations have indicated that appropriate unsteady excitation can delay boundary layer separation and stall on airfoils. Work is in progress to determine the control requirements for helicopter(More)
This research investigated the feasibility of a plasma lens for wavefront control of coherent light sources. The approach is based on the relation between a plasma electron density and its index of refraction. The plasma was encapsulated in a hollow glass cylinder with at optical glass at its ends. Air in the glass cylinder was ionized using a dielectric(More)
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