摘要:
In a first preferred embodiment for an improved synthetic jet actuator, the orifice shape is altered by either a flap or adjusting the housing walls. If the flap is deployed outward from the wall just above the orifice of a synthetic jet actuator, the synthetic jet flow will be vectored upward, toward the flap. Similarly, if the upper wall forming the orifice is moved outward from the jet chamber interior with respect to an opposing wall forming the orifice, the flow will also vector upward. In the second preferred embodiment of an improved synthetic jet actuator, an opening in addition to the orifice, may be formed in one or more walls of the housing. A louver is aligned with the opening in the housing and permits fluid flow in only one direction, either into the chamber or out of the chamber. When the louver permits fluid flow into the chamber, the jet actuator can operate at high speeds since fluid can enter the chamber through a greater surface area. Another preferred embodiment for an improved synthetic jet actuator comprises two concentric tubular sections normal to an outside surface of a solid body). In operation, the innermost section is connected to a vacuum device and constantly pulls fluid down its length from the ambient fluid above the outer surface. Meanwhile, the outer section ejects fluid into the ambient environment by pulses. Such an operation will cause a synthetic fluid jet to form above the constant suction synthetic jet actuator.
摘要:
A synthetic jet actuator, which can be micromachined if desired, generates a synthetic jet stream characterized by a series of successive vortices that can be used for effectively entraining adjacent fluid. The synthetic jet actuator can be used to bend, or vector, a jet stream from another jet actuator. Further, because the synthetic jet actuator exhibits zero net mass flux, the synthetic jet actuator can be used within a bounded volume. In structure, the synthetic jet actuator comprises a housing defining an internal chamber and having an orifice. A flexible metallized diaphragm forms a wall of the housing and can change the volume of the chamber when moved. An electrode is disposed adjacent to and spaced from the diaphragm, and an electrical bias is imposed between the metallized diaphragm and the electrode by a control system to force movement of the diaphragm. As the diaphragm moves, the volume in the internal chamber changes and vortices are ejected from the chamber through the orifice.
摘要:
The present invention involves a system for altering the aerodynamic shape and/or fluid flow field about a solid body. The preferred embodiment comprises a synthetic jet actuator embedded in a solid body, with the jet orifice built into the body surface. The synthetic jet actuator generates a series of fluid vortices emanating from the orifice so as to entrain fluid external to the actuator chamber and form a synthetic jet stream. A recirculating flow region is formed along the solid body surface about the synthetic jet orifice. As a result the apparent aerodynamic shape of the body is altered. Consequently, if the solid body is placed in a fluid flow field, the entire fluid flow field is altered by the operation of the synthetic jet actuator.
摘要:
Synthetic jet actuator, which can be micromachined if desired, generates a synthetic jet stream characterized by a series of successive vortices that can be used for effectively entraining adjacent fluid. The synthetic jet actuator can be used to bend, or vector, a jet stream from another jet actuator. Further, because the synthetic jet actuator exhibits zero net mass flux, the synthetic jet actuator can be used within a bounded volume. In structure, the synthetic jet actuator comprises a housing defining an internal chamber and having an orifice. A flexible metallized diaphragm forms a wall of the housing and can change the volume of the chamber when moved. An electrode is disposed adjacent to and spaced from the diaphragm, and an electrical bias is imposed between the metallized diaphragm and the electrode by a control system to force movement of the diaphragm. As the diaphragm moves, the volume in the internal chamber changes and vortices are ejected from the chamber through the orifice.
摘要:
Disclosed are embodiments of apparatus for sorting particles in a fluid stream by size. In one embodiment of an apparatus for sorting such particles, a housing is provided, which defines a channel for a fluid stream containing particles. A suction channel is also provided, which terminates at a suction port. The suction port is positioned adjacent to the fluid stream. The suction channel may be configured to create a low pressure region and thereby redirect particles in the first fluid stream such that they may be sorted by size.
摘要:
Disclosed are embodiments of apparatus and methods for separating particles in a fluid stream by size. In one illustrative embodiment of an apparatus for separating such particles, a housing is provided, which defines a channel for a fluid stream containing particles. A suction channel is provided, which terminates at a suction port. The suction port is positioned adjacent to the fluid stream. A blowing channel terminating at a blowing port is also provided. The blowing port is positioned adjacent to the suction port such that the suction port is positioned in between the fluid stream and the blowing port. The blowing port and the suction port are configured to create a low pressure region and thereby redirect the first fluid stream towards the low pressure region.
摘要:
A device is disclosed that uses a flow-control methodology to control sprays at very high precision and frequency. The device is based on an enhanced Coanda effect. The control flow is selectively applied to the region in which we desire the jet to vector and control the profile (width) of the jet. The control flow is introduced through multiple control flow ports surrounding the primary nozzle and adjacent to the Coanda surface. By selectively opening and closing different control flow ports the motion and profile of the jet can be controlled.
摘要:
A thermoacoustic cooling system for cooling an object such as a microelectronic chip. Heat produced by the object is transferred to a thermoacoustic engine. The thermoacoustic engine may include a resonator defining a chamber. A stack may be positioned in the chamber with one side of the stack adjacent to the heat source, and the opposite side of the stack adjacent to air in the chamber having a relatively cooler temperature. One or more orifices may be formed in the resonator such that the acoustic power generated by the thermoacoustic engine creates a synthetic jet to circulate air and move the air away from the object being cooled. Thus, the heat produced by the object is used to power the thermoacoustic engine to thereby remove heat from the object. The thermoacoustic engine may use no moving parts and may require no external power source other than the object being cooled.
摘要:
A device is disclosed that uses a flow-control methodology to control sprays at very high precision and frequency. The device is based on an enhanced Coanda effect. The control flow is selectively applied to the region in which we desire the jet to vector and control the profile (width) of the jet. The control flow is introduced through multiple control flow ports surrounding the primary nozzle and adjacent to the Coanda surface. By selectively opening and closing different control flow ports the motion and profile of the jet can be controlled.
摘要:
A device is disclosed that uses a flow-control methodology to control sprays at very high precision and frequency. The device is based on an enhanced Coanda effect. The control flow is selectively applied to the region in which we desire the jet to vector and control the profile (width) of the jet. In one embodiment, the control flow is applied at the desired circumferential location by the action of a rotting disk with a flow passage of a size that spreads the jet the desired amount. The size of this flow passage may be controlled by using two overlapping disks with large holes in each. By rotating one disk relative to the other, the size of the resultant passage can be modified.