Abstract: A single fluidic feedback oscillator incorporates two independent time event measurement means, resulting in a highly accurate volumetric flowmeter that is independent of the properties and composition of the flowing fluid. Under certain circumstances, when the relationship between speed of sound and specific heat of the fluid is generally known, the oscillator provides for a highly accurate sonic velocimeter and consequently can be used as a calorimeter. The main components of the invention are a fluidic amplifier oscillator, and two sets of sensors located at separate locations in either the feedback channels of the oscillator or in the oscillating jet flow region.

Abstract: A single fluidic feedback oscillator incorporates two independent time event measurement means, resulting in a highly accurate volumetric flowmeter that is independent of the properties and composition of the flowing fluid. Under certain circumstances, when the relationship between speed of sound and specific heat of the fluid is generally known, the oscillator provides for a highly accurate sonic velocimeter and consequently can be used as a calorimeter. The main components of the invention are a fluidic amplifier oscillator, and two sets of sensors located at separate locations in either the feedback channels of the oscillator or in the oscillating jet flow region.

Abstract: A cardiac output monitoring system (10) includes a respiratory flowmeter (14) and a gas analyzer (20, 22) capable of determining cardiac output on a breath-by-breath basis by non-invasively measuring properties of respiratory gasses and applying the Fick principle. The gas analyzer has the capability to simultaneously quantify multiple gas concentrations, including inhaled and end-tidal concentrations of any constituent of respiratory gas mixtures of a known number of possible constituents, in real time on a breath-by-breath basis, by measuring independent properties of the mixture. The respiratory flowmeter determines the volumetric and mass flow rates of any gas/gasses as calculated from the product of measured total respiratory flow and the measured volumetric concentration in real time on a breath-by-breath basis.

Abstract: A method and apparatus for real time gas analysis involving determining individual concentrations of fluid constituents in a mixture of known constituents by measuring properties of the mixture and solving a set of equations, which relate the individual gas concentrations to the measured properties of the mixture, for the unknown individual gas concentrations. The individual concentrations of four gasses in a mixture are determined by: passing the mixture through a flowmeter, a capillary, an orifice, and a sonic oscillator; transducing temperature, pressure and acoustic frequency measurements taken from the sensors; determining the density, viscosity, and the specific heat of the mixture; forming three equations which respectively relate these three properties to individual gas concentrations; and solving the three equations and the constitutive equation which requires that the sum of the concentrations equal unity, for the four unknown individual gas concentrations.

Abstract: A gas analyzer (10) integrated into the main passageway (11) of a breathing circuit includes pressure-drop flow element (12) that measures a pressure drop across an orifice, an acoustic flowmeter (14) measures the speed of sound in the gas mixture, and a SAW device (20) from which the viscosity of the gas mixture is determined. The dielectric constant of the gas mixture is determined from the capacitance of spaced-apart charged plates of a capacitor (22) through which the mixture passes. The gas mixture density is determined from the measured pressure drop and flow rate, while the gas mixture specific heat is determined from the density and speed of sound in accordance with known relationships. The individual concentrations of five constituents of a mixture of gasses can be determined by solving five equations relating the independently measured properties of the gas mixture to the individual constituent concentrations.

Abstract: A method and apparatus for real time gas analysis involving determining individual concentrations of fluid constituents in a mixture of known constituents by measuring properties of the mixture and solving a set of equations, which relate the individual gas concentrations to the measured properties of the mixture, for the unknown individual gas concentrations. The individual concentrations of four gasses in a mixture are determined by: passing the mixture through a flowmeter, a capillary, an orifice, and a sonic oscillator; transducing temperature, pressure and acoustic frequency measurements taken from the sensors; determining the density, viscosity, and the specific heat of the mixture; forming three equations which respectively relate these three properties to individual gas concentrations; and solving the three equations and the constitutive equation which requires that the sum of the concentrations equal unity, for the four unknown individual gas concentrations.

Abstract: A modular apparatus for analyzing a fluid includes a disposable fluidic sensor module, a replaceable transducer module, and an expendable electronics package. The disposable fluidic sensor includes a fluidic flowmeter and a capillary structure formed in a plate-like member which receives a sample fluid flow. The fluidic flowmeter is responsive to the fluid flow to generate an output indicative of the flow rate of the fluid, and the capillary structure restricts the fluid flow such that a pressure drop across the capillary structure is related to the viscosity of the fluid. The fluidic flowmeter can be a fluidic oscillator whose oscillation frequency is related to the fluid flow rate. The oscillator flowmeter also serves as an orifice, with the pressure drop across the oscillator being related to the density of the fluid.

Abstract: A process for cleansing microorganisms from the pliant epidermal surface of a human hand which comprises brushlessly scrubbing the pliant epidermal surface of the human hand with a plurality of cleansing fluids. The cleansing fluids are oscillating sprays which are sprayed onto the epidermal surface at a frequency of 20-80 HZ and at a temperature of 40-50° C. thereby removing microorganisms present on the pliant epidermal surface.

Abstract: Fluidic oscillators are used to apply pulsatile sweeping streams of a liquid, preferably a cleansing solution, to selected areas of epidermis in a manner consistent with the resonant characteristics of the epidermis. The device thereby cleanses the skin, pores, and folds of microorganisms.

Abstract: A method and apparatus for real time gas analysis involving determining individual concentrations of fluid constituents in a mixture of known constituents by measuring properties of the mixture and solving a set of equations, which relate the individual gas concentrations to the measured properties of the mixture, for the unknown individual gas concentrations. The individual concentrations of four gasses in a mixture are determined by: passing the mixture through a flowmeter, a capillary, an orifice, and a sonic oscillator; transducing temperature, pressure and acoustic frequency measurements taken from the sensors; determining the density, viscosity, and the specific heat of the mixture; forming three equations which respectively relate these three properties to individual gas concentrations; and solving the three equations and the constitutive equation which requires that the sum of the concentrations equal unity, for the four unknown individual gas concentrations.

Abstract: Reduction or cancellation of acoustic noise is achieved by providing an amplified, oppositely phased version of the noise by means of an acousto-fluidic amplifier. The amplified acoustic output noise is delivered through an impedance matching horn in destructively interfering relation with the original noise. Depending on the acoustic noise source and its spatial distribution, the acousto-fluidic amplifier may be a single stage amplifier or multiple stages connected in parallel and/or cascade, with output horns spatially distributed to have the maximum cancellation effect. Sensed noise, prior to fluidic amplification, may be processed in a manner to effect feedback or feedforward control of the amplified acoustic output signals.

Abstract: A continuous oxygen content monitor has a reference electrode embedded in a powdered chrome-chrome-oxide mixture and a counter electrode embedded in an elongate alumina-graphite sleeve which acts as the probe support body. Two hallow and spacer ablative steel domes encase the reference electrode and an intermediate air gap spacing and provide insulation to prevent thermal shock from damaging the monitor during insertion into the metal melt. A circuit provides counter emf across the sensing electrodes to prevent ion depletion of the reference material.

Abstract: A fluidic sound amplification system couples successive laminar proportional amplifiers through acoustic radiation between output and input horns to avoid the propagation of null offset signals. A second approach to obviating DC null bias in a fluidic sound amplification system comprises splitting the input signal, effecting a selected time delay on a portion of the signal such that the bandpass frequencies and dead zones or cancellation frequencies respectively of the amplified signals are 180.degree. out of phase and combine to produce a near uniform frequency response. A third approach is to use multiple parallel elements in each stage of amplification in such a manner that mechanical errors cancel each other out.

Abstract: A vortex chamber fluid pulser selectively produces pressure pulses in fluid flowing therethrough by the alternating insertion and retraction of a flow-disrupting tab into and out of an annular vortex chamber having an inlet and a pair of opposed axial outlets. Insertion of the tab disrupts the normally radial flow of fluid through the chamber and outlets causing the flow to become vortical; retraction of the tab causes a second pressure pulse as the flow returns to radial, sending a sequence of pressure pulses capable of carrying encoded signals to a transducer remotely located in the fluid.

Abstract: A postmix beverage dispenser valve including a fluidic oscillator flowmeter in conjunction with a master controller and a flow control valve such as a proportional solenoid. The frequency of the syrup oscillations in the fluidic oscillator is linearly related to the syrup velocity and thus to the volume flow rate. Various sensors can be used to detect the fluid oscillations with the preferred one being a piezo electric film transducer having a protective coating and used with a flex cavity in the conduit wall. A pressure compensation device can be used to isolate the solenoid armature from varying syrup pressures.

Abstract: A protective sheath for a temperature sensing device for use in determining the temperature of molten metals. The temperature sensing device, such as a thermocouple, is encased in a molybdenum tube which is coated with successive porous layers of molybdenum, a plurality of layers of Al.sub.2 O.sub.3 -Cr.sub.2 O.sub.3 -Mo in a decreasing concentration of Mo in proceeding from the inner to the outer layers, and a layer of substantially pure Al.sub.2 O.sub.3 -Cr.sub.2 O.sub.3. The Al.sub.2 O.sub.3 -Cr.sub.2 O.sub.3 layer may be covered with an outer coating of a material, such as boron nitride, to protect the Al.sub.2 O.sub.3 -Cr.sub.2 O.sub.3 layer from attack by slag. Alternating layers of Al.sub.2 O.sub.3 -Cr.sub.2 O.sub.3 and boron nitride may be applied as outermost sacrificial layers.

Abstract: A protective sheath for a temperature sensing device for use in determining the temperature of molten metals. The temperature sensing device, such as a thermocouple, is encased in a molybdenum tube which is coated with successive porous layers of molybdenum, a plurality of layers of Al.sub.2 O.sub.3 --Cr.sub.2 O.sub.3 --Mo in a decreasing concentration of Mo in proceeding from the inner to the outer layers, and a layer of substantially pure Al.sub.2 O.sub.3 --Cr.sub.2 O.sub.3. The Al.sub.2 O.sub.3 --Cr.sub.2 O.sub.3 layer may be covered with an outer coating of a material, such as boron nitride, to protect the Al.sub.2 O.sub.3 --Cr.sub.2 O.sub.3 layer from attack by slag. Alternating layers of Al.sub.2 O.sub.3 --Cr.sub.2 O.sub.3 and boron nitride may be applied as outermost sacrificial layers.

Abstract: A full wave fluidic rectifier which produces a direct fluidic output signal having an amplitude which increases from a very low level as the amplitude of an alternating fluidic input signal increases. In includes a nozzle for directing a fluid stream along the rectifier axis into a null venting outlet, two signal outlets which are symmetrically disposed in opposite sides of the null outlet, and two control signal inlets for applying the alternating input signal to the stream, deflecting the stream alternately toward the two signal outlets in proportion to the amplitude of the alternating input signal. The two signal outlets are connected by respective channels of equal fluid resistance to a common channel which serves as the rectifier output.

Abstract: A photofluidic interface that transduces optical control signals into fluid ontrol pressures is provided in which an AC modulated light source is utilized to transmit control signals to a photo acoustic cell that absorbs the light energy and converts it to heat energy thus creating pressure pulses within the cell. The output signal of the photo acoustic cell is then fluidically amplified, fluidically rectified and again fluidically amplified to create an output signal that drives an actuator.

Abstract: A broad band flueric amplifier is disclosed which comprises means to incre the deflection of the fluid jet within the amplifier at higher frequencies of oscillation of the jet. The means for increasing jet deflection comprises vanes or protrusions positioned closely adjacent the jet path at selected distances from the nozzle. Acoustic feedback from these vanes or protrusions will assist the control pulse in deflecting the jet at selected frequencies of oscillation.