Abstract: A vertical axis wind turbine comprises upper and lower rotor blades and upper and lower bearing assemblies. Horizontal members connect the upper rotor blades to the upper bearing assembly and the lower blades connect the upper rotor blades to the lower bearing assembly. The upper rotor blades can be arranged vertically or non-vertically. In non-vertical arrangements, the upper rotor blades can be twisted or swept back in a straight manner. Sweeping jet actuators are incorporated into the rotor blades to deliver oscillating air jets to surfaces of the rotor blades to delay occurrence of dynamic stall. Conduits in the blades can deliver pressurized flow of air to the actuators. The turbine can be supported by a structure that can exerts only horizontal and/or lifting forces on the rotor blade assembly to reduce the load on the lower bearing.

Abstract: A vertical axis wind turbine comprises upper and lower rotor blades and upper and lower bearing assemblies. Horizontal members connect the upper rotor blades to the upper bearing assembly and the lower blades connect the upper rotor blades to the lower bearing assembly. The upper rotor blades can be arranged vertically or non-vertically. In non-vertical arrangements, the upper rotor blades can be twisted or swept back in a straight manner. The turbine can be self-supporting with a need for a continuous vertical axis connecting the bearing assemblies. Sweeping jet actuators are incorporated into the rotor blades to deliver oscillating air jets to surfaces of the rotor blades to delay occurrence of dynamic stall. Conduits in the blades can deliver pressurized flow of air to the actuators. The turbine can be supported by a structure that can exerts only horizontal and/or lifting forces on the rotor blade assembly to reduce the load on the lower bearing.

Abstract: Apparatus for the interference and manipulation of vortex formation and control of fluid flow to reduce noise and increase flow stability is provided. A specific embodiment is directed to a flexible jet noise suppressor for aircraft, particularly supersonic transport. The jet noise suppressor comprises at least one flexible filament having a length that is about 3 to 10 nozzle diameters. The filament(s) trail behind the nozzle and may be let out for take-off and climb and reeled in while the aircraft is in flight or on the ground. Surprisingly, the use of a single flexible filament eliminates the well-known "screech noise" at about 3,000 Hz and reduces the screech noise by about 50 dB while further reducing the broad band noise up to 15 dB over the entire sound spectrum.