132 results about "Fluidic oscillator" patented technology

A fluidic oscillator suitable for use at colder temperatures for generating an exhaust flow in the form of an oscillating spray of fluid droplets has an inlet for pressurized fluid, a pair of power nozzles configured to accelerate the movement of the pressurized fluid, a fluid pathway that connects and allows for the flow of pressurized fluid between its inlet and the power nozzles, an interaction chamber which is attached to the nozzles and receives the flow from the nozzles, a fluid outlet from which the spray exhausts from the interaction chamber, and a means for increasing the instability of the flow from the power nozzles, with this means being situated in a location chosen from the group consisting of a location within the fluid pathway or proximate the power nozzles. In a first preferred embodiment, the flow instability generating means comprises a protrusion that extends inward from each side of the fluid pathway so as to cause a flow separation region downstream of the protrusions. In a second preferred embodiment, the flow instability generating means comprises a step in the height elevation of the floor of the power nozzles with respect to that of the interaction chamber.

A spirometer for measuring fluid flow, particularly associated with exhalation of respiratory patients. The spirometer of this invention preferably has a fluidic oscillator wherein the fluid oscillates within a chamber of the fluidic oscillator. An oscillation frequency of the fluid flow within the chamber is correlated to a flow rate. A computer is used to process input data, such as data representing frequency of the oscillatory flow within the chamber, to a flow rate passing through the spirometer. The spirometer of this invention may have no moving parts, which results in the need for only a design calibration and no periodic calibrations throughout use of the spirometer.

A fluidic oscillator suitable for use at colder temperatures for utilizing a pressurized liquid to generate a uniform spatial distribution of droplets has (a) an inlet for the pressurized liquid, (b) a set of three power nozzles that are fed by the pressurized liquid, (c) an interaction chamber attached to the nozzles and which receives the flow from the nozzles, wherein this chamber has an upstream and a downstream portion, with the upstream portion having a pair of boundary edges and a longitudinal centerline that is approximately equally spaced between the edges, and wherein one of the power nozzles is directed along the chamber's longitudinal centerline, (d) a throat from which the liquid exhausts from the interaction chamber, and (e) an island located in the interaction chamber, with this island being situated downstream of the power nozzle that is directed along the chamber's longitudinal centerline. In a preferred embodiment, this oscillator is further configured such that: (i) one of the power nozzles is located proximate each of the chamber's boundary edges, (ii) its nozzles are configured to accelerate the movement of the liquid that flows through the nozzles, (iii) its throat has right and left sidewalls that diverge downstream, and (iv) the power nozzles and island are oriented and scaled such as to generate flow vortices behind the island that are swept out of the throat in a manner such that these vortices flow alternately proximate the throat's right sidewall and then its left sidewall.

An improved fluidic device that operates on a pressurized liquid flowing through it at a specified flow rate to generate an oscillating spray of liquid droplets having desired properties (e.g., average spatial distribution, size, velocity, frequency and wavelength of liquid droplets at a defined distance in front of the device) includes: (a) a plurality of fluidic oscillators, each having a channel that is part of a fluidic circuit for inducing oscillations in the pressurized liquid that flows through the oscillator, (b) a housing having an exterior surface that includes a front face with a center-point and a rear face, (c) a plurality of passages, each of which extends through the housing and intersects with its front face to define an outlet, with each passages configured to allow for the insertion of one of the plurality of fluidic oscillators into each of the plurality of passages, and (d) a geometrical arrangement of these outlets in the housing front face that is chosen so as to achieve the desired properties of the oscillating spray when the device is operating at its specified flow rate.

For those spray applications that use a fluidic oscillator of the type that generates a spray by having a pressurized liquid flow through the oscillator and exhaust into a surrounding environment, and where such an oscillator has a boundary surface which has fabricated into it a channel in the form of what is referred to herein as fluidic circuit, an improved enclosure for this oscillator includes: a body having an interior and an exterior surface, wherein a portion of this interior surface is configured to attach to the oscillator boundary surface so as to form with the oscillator's channel an enclosed pathway through which the to-be-sprayed liquid may flow, and wherein a segment of this interior surface is configured so as to yield specified properties of the resulting spray.

A fluid spraying or nozzle system adapted for use with cold fluids, viscous fluids or fluids under light pressure includes a fluidic oscillator having a power nozzle and an oscillation chamber coupled to the power nozzle for issuing a jet of fluid into the oscillation chamber and an outlet aperture spraying a jet of fluid into ambient space. The oscillator's walls define an oscillation inducing interaction region causing the jet of fluid to rhythmically sweep back and forth between the sidewalls in the oscillation chamber. The oscillation inducing interaction region defines an outlet throat width which is adapted to work with the power nozzle's width and an a bell-shaped feed that spreads the fluid jet as it leaves the power nozzle, so that the interaction region and feedback channels are quickly filled with fluid at a low pressure and the fluidic oscillator is activated to generate a desired fan pattern of fluid spray.