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In this research, the magnetoplasmadynamic (MPD) effects of applying a toroidal magnetic field around an ionized exhaust plume were investigated to manipulate the exhaust profile of the plasma jet under near vacuum conditions. Tests for this experiment were conducted using the West Virginia University (WVU) Hypersonic Arc Jet Wind Tunnel. A series of twelve N52 grade neodymium magnets were placed in different orientations around a steel toroid mounted around the arc jet’s exhaust plume. Four different magnet orientations were tested in this experiment. Two additional configurations were run as control tests without any imposed magnetic fields surrounding the plume. Each test was documented using a set of 12 photographs taken from a fixed position with respect to the flow. The photographic data was analyzed by comparing images of the exhaust plume taken 10, 20, and 30 seconds after the plasma jet was activated.

The dielectric barrier discharge (DBD) has been studied significantly in the past two decades for its applications to various aerodynamic problems. The most common aerodynamic applications have been stall/separation control and boundary layer modification. Recently several researchers have proposed utilizing the DBD in various configurations to act as viable propulsion systems for micro and nano aerial vehicles. The DBD produces stable atmospheric-pressure non-thermal plasma in a thin sheet with a preferred direction of flow. The plasma flow, driven by electrohydrodynamic body forces, entrains the quiescent air around it and thus develops into a low speed jet on the order of 10-1 to 101 m/s. Several researchers have utilized DBDs in an annular geometric setup as a propulsion device. Other researchers have used them to alter rectangular duct flows and directional jet devices. This study investigates 2-D duct flows for applications in micro plasma thrusters.

The downwash of the prop-rotor blades of the Bell/Boeing V-22 “Osprey” in hover mode creates an undesirable negative lift on the wing of the aircraft. This downforce can be reduced through a number of methods. Neglecting all other effects, such as power requirements, this research investigated the feasibility of using circulation control, through blowing slots on the leading and trailing edge of the airfoil to reduce the wake profile under the wing. A model was built at West Virginia University (WVU) and tested in a Closed Loop Wind Tunnel. The airfoil was placed normal to the airflow using the tunnel air to simulate the vertical component of the downwash experienced in hover mode. The standard hover mode flap angle of 67 degrees was used throughout the testing covered in this paper. All of these tests were conducted at a free stream velocity of 59 fps, and the baseline downforce on the model was measured to be 5.45 lbs.

Corona discharge from a RF quarter wave coaxial cavity resonator is considered as a plasma ignition source for spark ignited (SI) internal combustion (IC) engines. The gaseous discharge processes associated with this device are analyzed using principles of gas kinetics and gaseous electronics, with assumed values for the electric field strength. Corona discharge occurs when the electric field shaped and concentrated by a single electrode exceeds the breakdown potential of the surrounding gas. Ambient electrons, naturally present due to ionizing radiation, drift in the direction of the externally applied field, gaining energy while undergoing elastic collisions with neutral molecules. After gaining sufficient energy they dissociate, excite, or ionize the neutral particles through inelastic collision, creating additional electrons. This process leads to avalanche electrical breakdown of the gas within about 10-8 sec.