Abstract: A microelectromechanical (MEM) device for controlled movement of a fluid. The device includes a chamber having a heating element, an inlet, and a constricted egress channel.

Abstract: The invention provides a method and apparatus for suppressing hydrodynamic cavitation through the use of high frequency (>500 kHz) and high amplitude (>1 atmospheres) acoustic energy. The method includes biasing a transducer driving signal to generate an acoustic field having a positive pressure halves. The resulting acoustic field is imposed on a region where cavitation is to be preempted. A cavitation preempting acoustic field in the liquid is similar in effect as using a hyperbaric confinement for imposing hydrostatic pressure, a known method for suppressing cavitation. In this regime, suppression of cavitation will be due to imposing a dominant high amplitude, high-frequency pressure field to ensure that the gaps between the compressive pulses are shorter than 10?7 to 10?6 seconds, which is less than that typically necessary to cause cavitation.

Abstract: A device for interrupting or throttling undesired ionic transport through a fluid network is disclosed. The device acts as a fluid valve by reversibly generating a fixed “bubble” in the conducting solvent solution carried by the network. The device comprises a porous hydrophobic structure filling a portion of a connecting channel within the network and optionally incorporates flow restrictor elements at either end of the porous structure that function as pressure isolation barriers, and a fluid reservoir connected to the region of the channel containing the porous structure. Also included is a pressure pump connected to the fluid reservoir. The device operates by causing the pump to vary the hydraulic pressure to a quantity of solvent solution held within the reservoir and porous structure. At high pressures, most or all of the pores of the structure are filled with conducting liquid so the ionic conductance is high.

Abstract: These and other objects of the present invention are achieved by provision of a flow through ultrasonic system for facilitating the flow of flow-resistant materials. The system includes a supply of material and an ultrasonic horn having at least one passage extending therethrough. An isolating tube which is compatible with the material is provided passing through the at least one passage in the ultrasonic horn, the isolating tube in communication the supply of material and completely isolating the ultrasonic horn from the material. A converter imparts ultrasonic energy to the ultrasonic horn, and in turn to the isolating tube so as to inhibit the material from attaching to and clogging the isolating tube.

Abstract: A modular microfluidic system includes a plurality of discrete microfluidic modules each capable of performing at least one operation and at least one microfluidic coupling device for fluidically coupling the modules to perform a sequence of operations. The microfluidic modules and coupling devices may be constructed according to various techniques. In one embodiment, coupling devices are fabricated from multiple layers and each include a fluidic inlet port, a fluidic outlet port, and at least one sandwiched stencil layer having a microfluidic channel formed therein. Also described are integrated microfluidic systems and methods capable of performing various sequences of operations.

Abstract: An apparatus and method for selectively draining melt material, such as molten salt, utilizes an unobstructed drain conduit detachably connected, as by screw threads, to a vessel containing the material. Two heaters are utilized for the conduit, a drain heater at the vessel and a plugging heater spaced from the vessel. The conduit is placed at the plugging heater and partially filled with a predetermined quantity of plugging material in flowable form. The plugging material is, typically, the same salt in particulate form and is retained in the conduit by any suitable closure. The plugging heater is energized to melt the plugging material and is then de-energized so that a solid plug of this material forms in the conduit. The conduit, including the plug, is removed from the closure and the plugging heater and is connected to the vessel when the drain heater is de-energized and when the vessel does not contain molten melt material, as when the vessel is empty or this material is solidified.

Abstract: A device for interrupting or throttling undesired ionic transport through a fluid network is disclosed. The device acts as a fluid valve by reversibly generating a fixed “bubble” in the conducting solvent solution carried by the network. The device comprises a porous hydrophobic structure filling a portion of a connecting channel within the network and optionally incorporates flow restrictor elements at either end of the porous structure that function as pressure isolation barriers, and a fluid reservoir connected to the region of the channel containing the porous structure. Also included is a pressure pump connected to the fluid reservoir. The device operates by causing the pump to vary the hydraulic pressure to a quantity of solvent solution held within the reservoir and porous structure. At high pressures, most or all of the pores of the structure are filled with conducting liquid so the ionic conductance is high.

Abstract: Disclosed is a micro flowguide device comprising: a micro channel comprising at least one bubble trap to retard bubbles positioned in said bubble trap; an electrolytic bubble generating device to generate bubbles in said fluid by an electrolytic reaction; and a pressure source to supply a suited pressure to said fluid to pass through said micro channel; wherein said electrolytic bubble generating device causes bubbles to be generated at areas adjacent to said at least one bubble trap. Electrolytic bubbles are generated through a, localized electrolytic reaction enabled by the exposure of a set of DC-source-connected electrodes inside a conduit branch. Accumulated bubbles will be trapped and kept at several traps of the invented flowguide. When the backward pressure of trapped bubbles is rising to the level of forward pressure head, flow speed reduces to zero and channel branch is shut down.

Abstract: A compact, inexpensive pipe freezer with defrost cycle for forming a frozen ice plug in a section of pipe to be repaired, and, after the repair operation has been completed, defrosting the pipe freezer's evaporator and freeze heads so that the pipe freezer can be removed from the frozen pipe without damaging the pipe freezer.

Abstract: A method is provided for fabricating a microstructure using maskless lithography. A first layer is provided in a spaced relationship to a base layer so as to define a construction cavity therebetween. The first layer has a passageway therethrough that communicates with the construction cavity. The construction cavity is filled with material and a polymerizing agent is directed towards a portion of the material so as to polymerize the same. The polymerized material defines a channel network and the non-polymerized material is flushed from the channel network.

Abstract: A method of simply controlling the flow of fluid in a micro system without using a complicated value structure, comprising the steps of adding the substance transformed from sol-gel by stimulation to the fluid flowing through the micro flow passage of the micro system, and adding the stimulation to the fluid at a desired position on the micro flow passage to transform the fluid into gel for flow control.

Abstract: A fluidic valve (125, 300, 500, 900, 1000, 1100, 1200, 1300) switches a state of flow of a fluid in a fluid communication channel of a fluid guiding structure (505). Heating a bi-phase valve element (515, 1065, 1215) causes a change a state of the bi-phase valve element from a high viscosity state to a low viscosity state. A bi-phase valve element that clogs the fluid communication channel can be pushed into an expanded portion (135, 320, 520, 915, 1220) of the fluid communication channel by an application of pressure to the fluid while the bi-phase valve element is in the low viscosity state, unclogging the fluid communication channel. A bi-phase valve element can be pushed from a valve element source chamber (550, 1250) into the fluid communication channel by using a pumped fluid entering the source chamber at a pump inlet (551) while the bi-phase valve element is in the low viscosity state, clogging the fluid communication channel.

Abstract: A fluidic valve (125, 300, 500, 900, 1000, 1100, 1200, 1300) switches a state of flow of a fluid in a fluid communication channel of a fluid guiding structure (505). Heating a bi-phase valve element (515, 1065, 1215) causes a change a state of the bi-phase valve element from a high viscosity state to a low viscosity state. A bi-phase valve element that clogs the fluid communication channel can be pushed into an expanded portion (135, 320, 520, 915, 1220) of the fluid communication channel by an application of pressure to the fluid while the bi-phase valve element is in the low viscosity state, unclogging the fluid communication channel. A bi-phase valve element can be pushed from a valve element source chamber (550, 1250) into the fluid communication channel by using a pumped fluid entering the source chamber at a pump inlet (551) while the bi-phase valve element is in the low viscosity state, clogging the fluid communication channel.

Abstract: A fine channel device capable of producing fine particles in an industrial scale, hardening the fine particles immediately after the production and recovering the fine particles from a medium without collapsing the shape of the produced fine particles, a fine particle producing method using the fine channel device and a solvent extraction method using the fine channel, are presented. The fine channel device comprises a fine channel provided with an inlet port and an inlet channel which feed a dispersion phase, an inlet port and an inlet channel which feed a continuous phase, and an outlet channel and an outlet port which discharge fine particles produced by the dispersion phase and the continuous phase, wherein the inlet channel for feeding the dispersion phase and the inlet channel for feeding the continuous phase are joined at an arbitrary angle, and the two inlet channels are connected to the outlet channel at the arbitrary angle.

Abstract: A microfluidic system includes a bubble valve for regulating fluid flow through a microchannel. The bubble valve includes a fluid meniscus interfacing the microchannel interior and an actuator for deflecting the membrane into the microchannel interior to regulate fluid flow. The actuator generates a gas bubble in a liquid in the microchannel when a sufficient pressure is generated on the membrane.

Abstract: A microfluidic system is provided for controlling delivery and mixing of thermally-responsive fluids. A plurality of microfluidic inlet channels open into a mixing chamber. A valve is associated with each of the inlet channels for controlling the flow of the thermally-responsive fluids through the inlet channels. The valves include a heater in thermal contact with at least a portion of the associated inlet channel, whereby the viscosity of the thermally-responsive fluids can selectively be controlled by heat to cause a change in flow of the thermally-responsive fluids through the inlet channels. A plurality of microfluidic outlet channels may be provided for transporting mixed fluids from the mixing chamber. A valve associated with each of the outlet channels controls the flow of the mixed thermally-responsive fluids through the outlet channels.

Abstract: A method is provided for fabricating a constriction region in a channel of a microfluidic device. The method includes the steps of introducing a pre-polymer mixture including a monomer, cross-linking agent and photoinitiator into the channel. The pre-polymer mixture is polymerized at a localized area of the channel so as to shrink and solidify the liquid mixture. The solidified and shrunken liquid mixture provides the constriction region in the channel.

Abstract: An apparatus and method for controlling the extrusion of thermoplastic through one or more discharge orifices is described. An apparatus comprises one or more thermally conductive flow tubes defining flow channels in a heated thermally conductive body and terminating in discharge orifices. Each flow channel may be independently valved on and off, by selectively supplying a flow of coolant. An array of flow channels can be independently opened and closed in a predetermined pattern, so as to vary the extrudate configuration of thermoplastic emerging from the discharge orifices. By extruding thermoplastic layer-by-layer onto a base in this manner, a three-dimensional object may be formed.

Abstract: A microfluidic system is provided for controlling delivery and mixing of thermally-responsive fluids. A plurality of microfluidic inlet channels open into a mixing chamber. A valve is associated with each of the inlet channels for controlling the flow of the thermally-responsive fluids through the inlet channels. The valves include a heater in thermal contact with at least a portion of the associated inlet channel, whereby the viscosity of the thermally-responsive fluids can selectively be controlled by heat to cause a change in flow of the thermally-responsive fluids through the inlet channels. A plurality of microfluidic outlet channels may be provided for transporting mixed fluids from the mixing chamber. A valve associated with each of the outlet channels controls the flow of the mixed thermally-responsive fluids through the outlet channels.

Abstract: The fluidic drive for miniature acoustic-fluidic pump and mixer is comprised of an acoustic transducer attached to an exterior or interior of a fluidic circuit or reservoir. The transducer converts radio frequency electrical energy into an ultrasonic acoustic wave in a fluid that in turn generates directed fluid motion through the effect of acoustic streaming. Acoustic streaming results due to the absorption of the acoustic energy in the fluid itself. This absorption results in a radiation pressure and acoustic streaming in the direction of propagation of the acoustic propagation or what is termed “quartz wind”.

Abstract: Methods and devices for the management of fluid flow within nanoscale analytical systems, comprising a freeze thaw valve having differing geomentries to constrict a frozen plug within the freeze thaw segment. The freeze thaw valve is directed to use in high-pressure analytical systems. The geometry of an inner diameter of a channel or tube within a freeze thaw segment is configured to cause constriction of a freeze plug when axial force is applied. The constriction is used in the flow-path of a freeze thaw valve to prevent movement of the frozen plug at high pressures to avoid valve leakage.

Abstract: Methods and devices for the management of fluid flow within nanoscale analytical systems, comprising a freeze thaw valve having differing geomentries to constrict a frozen plug within the freeze thaw segment. The freeze thaw valve is directed to use in high-pressure analytical systems. The geometry of an inner diameter of a channel or tube within a freeze thaw segment is configured to cause constriction of a freeze plug when axial force is applied. The constriction is used in the flow-path of a freeze thaw valve to prevent movement of the frozen plug at high pressures to avoid valve leakage.

Abstract: The invention discloses a method for fine control of the flow rate of a liquid by a microvalve device without using any mechanical structures. The method comprises, while passing the liquid through a flow channel penetrating a substrate of a heat-insulating material, the temperature of the liquid in the flow channel is decreased below the freezing point of the liquid by a temperature-controlling means such as a Peltier element facing the flow channel to close the flow channel by the solidified liquid and the temperature of the solidified liquid is increased above the melting point thereof to cause thawing of the solid resulting in re-opening of the flow channel.

Abstract: Fluid and fuel delivery systems reducing pressure fluctuations and engines including such systems are disclosed. Such systems use a conduit that attenuates pressure fluctuations. Preferably, the conduit attenuates pressure fluctuations by reflecting a portion of a pressure wave within the fluid flow so that reflected pressure waves within the flow interfere with incident pressure waves within the flow, thereby reducing the pressure fluctuations in one embodiment, such a conduit may be formed as a quarter wave stub, in line with the fluid flow. Advantageously, exemplary of the invention, hoot noise in an engine may be reduced by damping pressure fluctuations in the fuel delivery system to the engine.

Abstract: An ultrasonic apparatus and a method for improving the transfer, delivery, and flow of viscous liquids including heavy fuel and lubricating oils, such as bunker, molten metals, molten bitumens, food products, and other heavy viscous liquids. The apparatus includes a housing and a means for applying ultrasonic energy to a portion of the pressurized liquid as the liquid passes through the housing. The housing includes a chamber adapted to receive viscous liquid under pressure, a second smaller chamber or vestibular cavity in communication with the chamber, an inlet adapted to supply the chamber with the pressurized liquid, and an exit orifice adapted to pass the liquid out of the housing. When the means for applying ultrasonic energy is excited, it applies ultrasonic energy to the pressurized liquid contained within the vestibular cavity without mechanically vibrating the tip.

Abstract: A micro-electromechanical system and method for continuous laminar fluid mixing. An embodiment of the invention described in the specification includes a mixing channel, a first delivery channel that is connected to the mixing channel, and a second delivery channel that is connected to the mixing channel. A first pump mechanism produces pulses in the first delivery channel. A second pump mechanism produces pulses in the second delivery channel. The first pulsed fluid stream and the second pulsed fluid stream merge in the mixing channel to form a mixed fluid. The pulses in the fluids operate to distort the interface between the fluids to facilitate diffusion between the fluids.

Abstract: A device (10) for treating a continuously moving liquid has a liquid inlet (12) and a liquid outlet (14) at opposite ends of a generally annular passage (16). The passage has a restriction (18) which is generally cylindrical and which, at its outlet (22) is formed with an annular shoulder (24) which provides an abrupt change in the diameter of the passage. An obstruction (26) in the form of a wire extends across the restriction (18) adjacent the outlet (22). The restriction (18) serves to increase the speed of liquid flowing through the passage, thus reducing the liquid pressure. The obstruction (26) also assists in reducing the liquid pressure. The device reduces the liquid pressure below a level at which cavitation occurs in order to induce cavitation.

Abstract: Microfluidic devices for splitting an established fluidic flow through a microfluidic channel among multiple downstream microfluidic channels include a plurality of elevated flow resistance regions to promote precise and predictable splitting. Each elevated resistance region imparts a flow resistance that is substantially greater than the characteristic resistance to established flow of its associated downstream channel. Elevated flow resistance regions may include one or more porous materials and/or alterations to the channel geometry of at least a portion of a downstream channel.

Abstract: The invention relates to a miniaturized fluid flow switch which enables a directed deflection or deviation of a fluidic test current injected into a fluidic carrier current. The aim of the invention it to provide a fluid flow switch which does not require any moveable parts and with which no restricting preconditions exist with regard to the fluid media to be used. To this end, the inventive switch is comprised of at least two carrier current channels (11, 12) and of a test current channel (2) which, together, open into a distribution chamber (3) to which at least two discharge channels (41, 42) connect. The carrier current channels (11, 12) are connected to a common inlet (10), and at least the carrier current channels (11, 12) are respectively placed, in particle sections, in close thermal contact with controllable heating devices (5).

Abstract: Control of fluid motion within microcavities is carried out using microstructures in the cavities having cantilever elements that are coupled to a substrate to receive vibrations therefrom. The cantilever elements can be excited into resonance at one or more resonant frequencies. By selection of the shape of the cantilever elements, their position in the microcavity, the spacing of the cantilever elements from the walls of the cavity, and the frequency at which the cantilever elements are excited, the direction of pumping of fluid through the cavity can be controlled, blocked or diverted.

Abstract: A device for moving a fluid in a fluidics system. The device may include one or more controllably openable closed chambers. The pressure within the closed chamber(s) is lower than the ambient pressure outside the fluidics system or lower than the pressure within another channel of the fluidic system. The closed chamber(s) is configured for being controllably opened. The chamber (or chambers) is configured such that when a chamber is opened the chamber is in fluidic communication with a flow channel included within the fluidics system. The fluid may be moved into the flow channel or may be moved within the flow channel. The fluid may be a liquid, a gas, a mixture of gases or an aerosol. The fluidics system may include a controller for controlling the opening of a selected chamber or chambers.

Abstract: An ultrasonic apparatus and a method for injecting a pressurized liquid fuel by applying ultrasonic energy to a portion of the pressurized liquid fuel. The apparatus includes a die housing which defines a chamber adapted to receive a pressurized liquid and a means for applying ultrasonic energy to a portion of the pressurized liquid. The die housing further includes an inlet adapted to supply the chamber with the pressurized liquid, and an exit orifice defined by the walls of a die tip. The exit orifice is adapted to receive the pressurized liquid from the chamber and pass the liquid out of the die housing. When the means for applying ultrasonic energy is excited, it applies ultrasonic energy to the pressurized liquid without applying ultrasonic energy to the die tip.

Abstract: A device for moving a fluid in a fluidics system. The device may include one or more controllably openable closed chambers. The pressure within the closed chamber(s) is lower than the ambient pressure outside the fluidics system or lower than the pressure within another channel of the fluidic system. The closed chamber(s) is configured for being controllably opened. The chamber (or chambers) is configured such that when a chamber is opened the chamber is in fluidic communication with a flow channel included within the fluidics system. The fluid may be moved into the flow channel or may be moved within the flow channel. The fluid may be a liquid, a gas, a mixture of gases or an aerosol. The fluidics system may include a controller for controlling the opening of a selected chamber or chambers.

Abstract: The invention discloses a method for fine control of the flow rate of a liquid by a microvalve device without using any mechanical structures. The method comprises, while passing the liquid through a flow channel penetrating a substrate of a heat-insulating material, the temperature of the liquid in the flow channel is decreased below the freezing point of the liquid by a temperature-controlling means such as a Peltier element facing the flow channel to close the flow channel by the solidified liquid and the temperature of the solidified liquid is increased above the melting point thereof to cause thawing of the solid resulting in re-opening of the flow channel.

Abstract: Fluid and fuel delivery systems reducing pressure fluctuations and engines including such systems are disclosed. Such systems use a conduit that attenuates pressure fluctuations. Preferably, the conduit attenuates pressure fluctuations by reflecting a portion of a pressure wave within the fluid flow so that reflected pressure waves within the flow interfere with incident pressure waves within the flow, thereby reducing the pressure fluctuations in one embodiment, such a conduit may be formed as a quarter wave stub, in line with the fluid flow. Advantageously, exemplary of the invention, hoot noise in an engine may be reduced by damping pressure fluctuations in the fuel delivery system to the engine.

Abstract: A microfluidic valve for controlling the flow of a material through a microfluidic channel comprising: a) a microfluidic channel comprising a passageway, b) a heater in contact with at least a portion of the microfluidic channel, c) a carrier fluid comprising the material and an amount of thermally-responsive material so that the carrier fluid can be thickened by heat from the heater to cause a reduction in flow of the carrier fluid through the microfluidic channel.

Abstract: A switching device for controlling fluid motion. The device includes a capillary filled with a first fluid into which a wall-confined bubble of a second fluid is introduced to achieve a first switching event. Capillary geometry and wetting properties provide a pressure-related asymmetric energy potential distribution for controlling the flow of the bubble, and the device is called an asymmetric bubble chamber, or ABC. The bubble is initially trapped in an energy potential well, and upon increase of its volume moves from the well into a region of low energy potential to achieve a second switching event. The first switching event may be blocking of a fluid channel or reflection of an optical beam in an optical crosspoint switch, while the second switching event may be unblocking of a fluid channel or restoration of transmission of an optical beam.

Abstract: A diffuser (7) has a step (12) in the surface (9) just upstream of a point where boundary layer separation might occur. An acoustic jet (22) has a nozzle (17) immediately downstream of the step (12); the acoustic jet is driven (25) by a plurality of frequencies, one or more of which are subharmonics of another of them, and having different phases.

Abstract: An improved double block and double bleed stream switching system (modifiable to, for example, a double block, single bleed stream switching system) includes a common stream path for a multitude of gas streams from, for example, a process pipeline. The improved stream switching system includes a heating mechanism and insulation oven to help temperature stabilization, along with a structure to separate temperature sensitive solenoids from the heated area. Pre-heat coils are located between the sample switching system and the sample shut off system to warm the gas sample and to act as a flow restrictor. A first embodiment is suited for the Division 1 environment and a second embodiment is suited for Division 2 uses. The improved stream switching system may also feature membrane or cartridge filters located upstream of the sample wetted portion of the stream switching system.

Abstract: An apparatus and a method for ultrasonically producing a spray of liquid. The apparatus includes a die housing which defines a chamber adapted to receive a pressurized liquid and a means for applying ultrasonic energy to a portion of the pressurized liquid. The die housing further includes an inlet adapted to supply the chamber with the pressurized liquid, and an exit orifice defined by the walls of a die tip. The exit orifice is adapted to receive the pressurized liquid from the chamber and pass the liquid out of the die housing to produce a spray of liquid. When the means for applying ultrasonic energy is excited, it applies ultrasonic energy to the pressurized liquid without applying ultrasonic energy to the die tip.

Abstract: The invention concerns a freeze vale (2) for controlling the flow of small quantities of liquid in a conduit (1). Further objects of the invention are a network of conduits, a method of opening a freeze valve and a process for the separation of liquid fractions, which all involve the freeze valves (2) of the invention. The freeze valve (2) s defined by a tubular wall (3) integral with the conduit (1) and includes a thermal bridge (4) connecting the wall to a heat sink (5), to close the valve by freezing the liquid inside the wall, as well as a heating element (11) including a source of laser beam targeted at a wall, to open the valve by melting the frozen liquid (7). According to the invention the laser beam (13) is produced in the form of a transversally extended shroud and targeted at the wall (3) at a length extending to both sides of the point of connection (6) to the thermal bridge (4), so as to melt the block of frozen liquid (7) simultaneously along its entire length.

Abstract: An apparatus and a method for ultrasonically producing a spray of liquid. The apparatus includes a die housing which defines a chamber adapted to receive a pressurized liquid and a means for applying ultrasonic energy to a portion of the pressurized liquid. The die housing further includes an inlet adapted to supply the chamber with the pressurized liquid, and an exit orifice defined by the walls of a die tip. The exit orifice is adapted to receive the pressurized liquid from the chamber and pass the liquid out of the die housing to produce a spray of liquid. When the means for applying ultrasonic energy is excited, it applies ultrasonic energy to the pressurized liquid without applying ultrasonic energy to the die tip.

Abstract: A system is provided for suppressing flow-induced cavitation in a fluid f. At least one acoustic transducer is coupled to the fluid flow in a region that is susceptible to the formation of cavitation bubbles. The transducer (or transducers) applies an acoustic field to the fluid flow in order to raise the cavitation threshold pressure of the fluid flow above the total local pressure including the pressure drop induced by the fluid flow and the pressure due to the acoustic field.

Abstract: A freeze valve for a substantially single-phase fluid contains a pipe designed to receive fluid in a flow area, a cold source and a heat source. The cold source and the heat source are placed in thermal contact with the pipe. The pipe is positioned in relation to the cold source and the heat source in such a way so as to permit the freezing of fluid passing through the pipe, thereby closing the passage through the pipe, or the heating of the fluid, thereby opening the passage. The pipe contains, for example, a metallic material that is mechanically strong and capable of dissipating heat by the Joule effect.

Abstract: A method and apparatus are provided for suppressing flow-induced cavitation n a fluid flow. At least one acoustic transducer is coupled to the fluid flow in a region that is susceptible to the formation of cavitation bubbles. The transducer (or transducers) applies an acoustic field to the fluid flow in order to raise the cavitation threshold pressure of the fluid flow above the total local pressure including the pressure drop induced by the fluid flow and the pressure due to the acoustic field.

Abstract: An ultrasonic apparatus and method for regulating the flow of a pressurized liquid through an orifice by applying ultrasonic energy to a portion of the pressurized liquid. The apparatus includes a die housing which defines a chamber adapted to receive a pressurized liquid and a means for applying ultrasonic energy to a portion of the pressurized liquid. The die housing further includes an inlet adapted to supply the chamber with the pressurized liquid, and an exit orifice defined by the walls of a die tip. The exit orifice is adapted to receive the pressurized liquid from the chamber and pass the liquid out of the die housing. When the means for applying ultrasonic energy is excited, it applies ultrasonic energy to the pressurized liquid without applying ultrasonic energy to the die tip and modifies the flow rate of the pressurized liquid the exit orifice.

Abstract: An ultrasonic apparatus and method for increasing the flow rate of a pressurized liquid through an orifice by applying ultrasonic energy to a portion of the pressurized liquid. The apparatus includes a die housing which defines a chamber adapted to receive a pressurized liquid and a means for applying ultrasonic energy to a portion of the pressurized liquid. The die housing further includes an inlet adapted to supply the chamber with the pressurized liquid, and an exit orifice defined by the walls of a die tip. The exit orifice is adapted to receive the pressurized liquid from the chamber and pass the liquid out of the die housing. When the means for applying ultrasonic energy is excited, it applies ultrasonic energy to the pressurized liquid without applying ultrasonic energy to the die tip.

Abstract: An analyte fluid stream with first molecules having relatively low molecular weight and a corresponding high coefficient of diffusion has reduced diffusional defocusing out of an analyte fluid stream. The analyte fluid stream of first molecules is associated with second molecules of relatively high molecular weight having a relatively low coefficient of diffusion and a binding constant effective to associate with the first molecules. A focused analyte fluid stream is maintained since the combined molecular weight of the associated first and second molecules is effective to minimize diffusion of the first molecules out of the analyte fluid stream.

Abstract: Turbulence is controlled in boundary layer or wall-bounded fluid flow fields having a turbulent wall region characterized by a system of roll pairs extending in the direction of flow, and obliquely propagating structures interacting with the system of roll pairs, by locally introducing into the turbulent wall region two separate disturbances that are effective to produce, in a local region, a composite disturbance field that is strongly coupled to and modifies the obliquely propagating structures in a manner that increases or decreases the interaction of the propagating structures with the system of roll pairs thereby locally increasing or decreasing the turbulence in the flow field. One of the disturbances may result from the interaction of the fluid with a linear strip, or an array of strips, of delta-shaped protrusions positioned spanwise on the wall (i.e., transverse to the flow direction); and the second disturbance may result from injecting sonic energy into the local region.

Abstract: A fluidic device is provided to control the path of a fluid. A control cher has at least one window incorporated therein that permits acoustic waves impinging thereon to pass therethrough. An ultrasonic source is remotely located with respect to the control chamber and a coupling medium, such as water, air or an acoustic waveguide, acoustically couples the acoustic waves to the window(s).