A method and apparatus for generating a wave in a body of water may include altering a flow of water as it is urged through an inlet, contoured passage, and outlet. For example, a primary flow of water may be altered so that one or more secondary flows are created at angles to the direction of primary flow.

A removable passive airflow oscillation device can be disposed within a pressurized wing structure utilized as a plenum. The passive airflow oscillation device can be a removable insert disposed into exterior vehicle surfaces with pressurization of a sealed chamber to provide the airflow. The device can include a cavity configured to receive the airflow from an ingress opening, direct the airflow therethrough to generate a predetermined oscillating airflow, and expel the oscillatory airflow from the egress opening. The removable passive airflow oscillation devices can provide quick and simple replacement and maintenance of damaged or clogged devices. The aft chamber of the flap seal can be sealed and pressurized to serve as a plenum providing the airflow to the actuators. The device can receive airflow, such as compressor air, and expel an oscillating airflow. Because each device is self-contained the number of devices and location thereof can vary by application.

A method and apparatus for generating a wave in a body of water may include altering a flow of water as it is urged through an inlet, contoured passage, and outlet. For example, a primary flow of water may be altered so that one or more secondary flows are created at angles to the direction of primary flow.

A removable passive airflow oscillation device can be disposed within a pressurized wing structure utilized as a plenum. The passive airflow oscillation device can be a removable insert disposed into exterior vehicle surfaces with pressurization of a sealed chamber to provide the airflow. The device can include a cavity configured to receive the airflow from an ingress opening, direct the airflow therethrough to generate a predetermined oscillating airflow, and expel the oscillatory airflow from the egress opening. The removable passive airflow oscillation devices can provide quick and simple replacement and maintenance of damaged or clogged devices. The aft chamber of the flap seal can be sealed and pressurized to serve as a plenum providing the airflow to the actuators. The device can receive airflow, such as compressor air, and expel an oscillating airflow. Because each device is self-contained the number of devices and location thereof can vary by application.

A flow conditioning assembly comprising an integral elbow flow conditioner and a downstream flow conditioner. The elbow flow conditioner includes a pipe elbow with one or more flow conditioning elements. Each flow conditioning element includes one or more turning guides. Each turning guide is generally circular and radially spaced from one another and an inner surface of the elbow. Spaced vanes maintain the radial spacing of the turning guides. The vanes divide the radial space between the turning guides and pipe elbow into a plurality of flow channels that turn in generally the same direction as the inner surface of the pipe elbow. The downstream flow conditioner comprises a flow conditioning structure within a pipe element. The flow conditioning structure includes one or more flow guides of generally circular form radially spaced from one another and the pipe element. Spaced support vanes maintain the radial spacing of the flow guides.

An arrangement to control vibrations in a gas turbine exhaust diffuser is provided. The arrangement includes a protrusion coupled to a turbine exhaust cylinder strut for controlling shock induced oscillations in a gas turbine diffuser. The controlled shock induced oscillations minimize pressure fluctuations in the gas turbine exhaust diffuser such that an unsteadiness of the fluid flow surrounding the turbine exhaust cylinder strut is reduced. A method to fluid flow induced vibrations in a gas turbine diffuser is also provided.

An apparatus comprises a surface that is configured to be exposed to a fluid stream and a cavity wall that forms at least a portion of a cavity. A first channel opening is formed in the surface, and a second channel opening is formed in the cavity wall. A channel extends from the first channel opening in the cavity wall to the second channel opening in the surface.

A structure adapted to traverse a fluid environment includes an elongate body having a root, a wingtip, a leading edge and a trailing edge; and a rigid winglet associated with the wingtip and having a winglet body extending substantially normal to one of a suction side and a pressure side of the elongate body to a termination point that is rearward of the trailing edge. In an embodiment, the structure is a rotor blade that may be incorporated into a wind turbine.

Retraction of a landing gear assembly on an aircraft is actuated by a hydraulic actuator. The actuator includes a piston that travels within a cylinder along a stroke length between a first position corresponding to the landing gear assembly when extended and a second position corresponding to the landing gear assembly when retracted. The movement of the piston along its stroke length is snubbed at one end by a different amount according to the direction of travel, for example by use of an orifice plate that has a discharge coefficient that is greater in one direction than in the opposite direction. Asymmetric snubbing is thus provided, which enables the landing gear to retract faster.

A wind-diverting apparatus for minimally shielding only the faster-moving drag-sensitive uppermost wheel surfaces from headwinds reduces overall vehicle drag. The apparatus includes various upper wheel fairings of FIGS. 1-6. Each fairing shields a primary vehicle-drag-inducing upper wheel surface from headwinds otherwise impinging directly thereon.