摘要:
A strain amplification structure has a frame with a hexagonal structure incorporating a plurality of rigid beams (16a) that are connected to opposing end beams by a plurality of flexible joints (24). A piezoceramic actuator assembly (26) is connected to the opposing end beams having a collar (32)including an opening. A shaft (18) providing an output is connected to the plurality of rigid beams with flexible joints and passes through the opening in the collar (32) for non-interfering motion orthogonal to the actuator assembly.
摘要:
A jet generator (100; 230) is controlled by providing an input signal at a variable frequency to the jet generator (100; 230) and to a simulated electrical load of the jet generator (100; 230), measuring a difference in signals between the jet generator (100; 230) and the simulated electrical load to identify an optimum flow of a jet generated by the jet generator (100; 230), and tuning the frequency of the input signal to maintain the jet at the optimum flow. (Fig. 2)
摘要:
A method and apparatus for managing a flow of a fluid. The fluid is received at an input port (206) of a structure (204). The fluid is sent through a chamber (210) in communication with the input port (206). The fluid is caused to flow from the chamber (210) and out of an output (208) port in a direction that changes with a frequency based on an application of pressure pulses in the chamber (210).
摘要:
This invention relates to an element (11) for generating a fluid dynamic force, the element (11) comprising first (13) and second (15) surfaces extending in opposite directions from a leading edge (17) of the element (11) and meeting at a trailing edge (18) thereof to define a three dimensional body that is shaped to generate a fluid dynamic force when immersed at an angle of attack α to a fluid flow over the element (11) in a flow direction U, the first surface (13) comprising an array of fluid inlets (19) and the second surface (15) comprising a corresponding array of fluid outlets (21), each said inlet (19) being fluidly coupled to a said outlet (21) by means of a fluid duct (23) at least part of which is pitched at an angle θ to a tangent plane (Y—Y) to said second surface (15) in the vicinity of said outlet (21) and skewed at an angle ϕ to said fluid flow direction U, the arrangement being such that the element (11) is operable in use to generate a relatively high fluid pressure region downstream of said leading edge (17) proximate said first surface (13) and a relatively low fluid pressure region downstream of said leading edge (17) proximate said second surface (15), and fluid from said relatively high fluid pressure region is enabled to flow into said fluid inlets (19) through said fluid ducts (23) and out of said fluid outlets (21) into said relatively low pressure region to generate fluid vortices which reenergise said low pressure region and delay boundary layer separation from said second surface (15).
摘要:
Disclosed is a flow element (1) comprising an external side (3) that has a top face (3a) and a bottom face (3b) in relation to the direction of flow, and lateral end sections (5a, 5b) that form the lateral ends of the flow element (1) transversal to the theoretical direction of flow (S). A duct (10) is arranged inside the flow element (1). Said duct (10) encompasses a flow drive with a driving motor and a compressor means which is driven by the driving motor and is disposed in the duct (10). The duct (10) has at least one inlet (11) on the bottom face (3b) and/or on at least one of the lateral end sections (5a, 5b) of the flow element (1) as well as an outlet (12) on the top face (3a) of the flow element (1) in order to influence the flow on the flow element (1). A sleeve (30) that can be rotated by means of the driving motor is located inside the duct (10). Said sleeve (30) has at least one cavity (33) which can be made to at least partially overlap with the outlet (12) on the top face (3a) of the flow element (1) in a specific rotational position of the sleeve (30) such that the air that is compressed by the compressor flows through the cavity (33) of the sleeve (30) and the outlet (12). A high-lift system comprising such a flow element is also disclosed.
摘要:
A method of causing a fluid flow to oscillate between two exit directions. The method comprises causing a primary flow of fluid though a conduit (330), the conduit (338) characterized by two exit directions (350,360) and providing first and second oscillation control ports (340), said first and second oscillation control ports transverse to said conduit and connected to one another by a feedback tube (440).
摘要:
Briefly described, the present invention is concerned with cooling heated bodies and/or heated fluid with synthetic jet actuators in either open or closed systems. A first preferred embodiment of a cooling system of the present invention comprises a synthetic jet actuator directed to impinge directly on a heat producing (or heated) body. The synthetic jet actuator generates a synthetic jet stream comprised of cool ambient fluid that impinges on the heated surface thereby cooling this surface. As an example, the heated surface/body could be a microchip array in a microcomputer. After coming into contact with the heated surface, the fluid moves along the surface and is finally rejected to the ambient where it mixes and cools down. The synthetic jet may be incorporated into a modular unit that may be clipped on to a circuit board or other heat producing element to provide added, 'ad hoc' cooling. In another configuration, a synthetic jet actuator may be positioned, relative to the heated surface, to create a synthetic jet stream to flow along the heated surface. In this embodiment, the flow would be approximately tangential to a surface of a heat producing body. This embodiment may further comprise a cyclical flow of the fluid jet, along the heated body and about a heat sink surface.