Abstract: A flowmeter for detecting gas flow rates in a pipe including a container configured to be attached to the pipe having a channel through which the gas flows, and a plurality of recesses that extend through the container and a plurality of housings. Each recess having one housing of the plurality of housings. Each housing having a pressure containing window. The flowmeter includes a plurality of transducers, with one transducer of the plurality of transducers disposed in each housing in each recess. The transducers transmitting ultrasonic signals through the windows into and receiving ultrasonic signals through the windows from the channel. The flowmeter includes acoustic isolators disposed about the housing along the housing's length and between the housings and the container which acoustically isolate the housings from the container.

Abstract: To measure the propagation time of an ultrasonic signal, the flow rate measuring device of the present invention has amplifier for amplifying a received signal, reference-voltage changing part, reference-voltage setting part, and reference comparator for comparing between the received signal waveform and reference voltage. Reference-voltage changing part changes the reference voltage according to the amplification degree of the amplified waveform of the received signal in amplifier. Comparing the changed reference voltage with the received signal waveform enhances stability in calculation of the propagation time. This prevents measurement accuracy of the flow velocity and the flow rate of fluid to be measured from degradation.

Abstract: A method for manufacturing an ultrasonic, flow measuring device, characterized by method steps as follows: selecting a number larger than one of straight subsections of the first signal path, which should have different distances from the measuring tube axis; establishing the distances of the straight subsections from measuring tube axis; calculating values of lengths of the straight subsections, as projected on the measuring tube axis, as a function of the number of straight subsections with the same distance from the measuring tube axis and the respective distances from the measuring tube axis; and inserting the at least a first reflection surface in the measuring tube such that the acoustic signal on the path from the first transmitter to the first receiver is so reflected on at least the first reflection surface that the first signal path comprises the straight subsections with the selected distances and the calculated values of the lengths as projected on the measuring tube axis.

Abstract: An ultrasonic flowmeter comprising an elongate duct through which fluid flows when the flowmeter is in use. Ultrasonic transducers are arranged respectively to transmit and receive ultrasonic pulses propagated through such fluid when the flowmeter is in use. Electronic circuitry is connected to the transducers to provide a measure of the time delay between emission of an electronic pulse from one of the transducers and reception of the pulse by the other of the transducers. The circuitry is constructed to enable an output to be provided which is dependent upon that delay and which is indicative of the rate of flow of fluid through the duct. The transducers are located respectively at opposite ends of the duct and are arranged to transmit and receive ultrasonic pulses propagated through the fluid substantially parallel to the duct from one end thereof to the other.

Abstract: An ultrasonic signal coupler includes a pipe having a first ultrasonic waveguide and a second ultrasonic waveguide penetrating the pipe so that ultrasonic transducers attached to ends of the ultrasonic waveguides communicate ultrasonic signals through the ultrasonic waveguides directly through a fluid traveling through the pipe.

Abstract: A system is provided with an ultrasonic flow meter. The ultrasonic flow meter includes a first ultrasonic transducer disposed about a fluid flow path, and a pressure balancing system configured to pressure balance the first ultrasonic transducer relative to a fluid flow along the fluid flow path.

Abstract: An ultrasonic flowmeter includes a meter body including a flow passage having wetted surfaces through which fluid flow is to be measured. The flowmeter includes a non-stick coating adhered to the wetted surfaces of the meter body. The flowmeter includes a first transducer and at least a second transducer arranged around the flow passage to transmit and receive ultrasonic energy. The flowmeter includes an electronic unit designed to generate and receive electronic signals from the transducers and to process the signals in order to compute information related to the fluid flow rate through the passage. A method for measuring fluid flow with an ultrasonic flowmeter. A method of making an ultrasonic flowmeter.

Abstract: The present invention discloses an ultrasonic flow meter comprising a generator circuit and a receiver circuit electrically separated from the generator circuit. The flow meter further comprises transducer switching means for controlled connection of ultrasonic transducers to either the generator circuit or to the receiver circuit. The output impedance of the generator circuit and the input impedance of the receiver circuit are controlled to be substantially zero.

Abstract: An ultrasonic flow meter unit, mounted to a fluid passage through which a measurement target fluid flows, comprises a pair of ultrasonic transducers each including a piezoelectric substrate, and an acoustic matching member; a measuring circuit which measures a flow of a target fluid based on time for which an ultrasonic pulse propagates between the pair of ultrasonic transducers; and an insulating damping member unitarily formed to cover at least a portion of each of a portion of each of the pair of ultrasonic transducers, which portion contacts the fluid passage, the piezoelectric substrate, and the measuring circuit.

Abstract: To measure the propagation time of an ultrasonic signal, the flow rate measuring device of the present invention has amplifier for amplifying a received signal, reference-voltage changing part, reference-voltage setting part, and reference comparator for comparing between the received signal waveform and reference voltage. Reference-voltage changing part changes the reference voltage according to the amplification degree of the amplified waveform of the received signal in amplifier. Comparing the changed reference voltage with the received signal waveform enhances stability in calculation of the propagation time. This prevents measurement accuracy of the flow velocity and the flow rate of fluid to be measured from degradation.

Abstract: An ultrasonic transducer comprises a metal plate; an acoustic matching member fastened to one of surfaces of the metal plate, a piezoelectric substrate which is fastened to the other surface of the metal plate and generates a vibration; and an insulating damping member covering a surface of the piezoelectric substrate which surface is on an opposite side of a surface fastened to the metal plate; wherein a thickness of the insulating damping member is set to a length which is n/2 of a wavelength of the vibration propagating through the insulating damping member.

Abstract: An ultrasonic flow rate measurement device capable of sensing and correcting a temperature without use of a sensor specifically designed for measuring a temperature is provided. The ultrasonic flow rate measurement device includes a first ultrasonic transducer and a second ultrasonic transducer that re disposed in a flow volume measurement block and arranged in such a way that ultrasonic waves are transmitted from one transducer and received by the other transducer; a counter for measuring a propagation time consumed for exchanging the ultrasonic waves between the first ultrasonic transducer and the second ultrasonic transducers; a flow volume computing block that calculates a flow volume from a measurement value of the counter; an oscillation circuit used as a time counter when the counter calculates the propagation time; and a temperature sensing block for sensing a temperature by utilization of a frequency change attributable to a temperature of the oscillation circuit.

Abstract: A method and system for measuring characteristics of an acoustic signal traveling through a fluid in a pipe uses an ultrasonic transducer attached directly to the pipe. The transducer is disposed in a housing attached to an outside surface of a flange of the pipe. The transducer fires an acoustic signal and its characteristics are measured.

Abstract: The present invention pertains to a flow conditioner for displacing and mixing fluid flow to minimize the effects of thermal gradients on the accuracy of a transit time ultrasonic flowmeter and defines an envelope in a cross sectional direction in a pipe having a first ramp adapted to be disposed in the pipe and extending from the outside of the envelope inward toward the center of the pipe in a downstream direction with respect to the fluid flow and forming an angle between 0° and 90° relative to the pipe's inner surface. The conditioner has a second ramp adapted to be disposed in the pipe and in juxtaposition with the first ramp, the second ramp extending from the outside of the envelope inward toward the center of the pipe in an upstream direction with respect to the fluid flow and forming an angle between 0° and 90° relative to the pipe's inner surface. An apparatus for determining fluid flow in a pipe having ultrasonic transducer sites. A method for determining fluid flow in a pipe.

Abstract: An ultrasonic flow meter is equipped with a housing through which a liquid flows, and a pair of detection units disposed on opposite ends of the housing and including acoustic wave transmitting and receiving units capable of transmitting and receiving acoustic wave signals. Paired connecting plugs are connected respectively to both ends of the housing. In addition, a supply passage of one of the connecting plugs, a conduit of the housing, and a discharge passage of another of the connecting plugs are disposed on a straight line. A liquid supplied to the supply passage flows through a passage of the conduit and to the discharge passage. Consequently, a flow rate of the liquid is measured based on the propagation time of the acoustic wave signals, which are transmitted and received by the acoustic wave transmitting and receiving units.

Abstract: An ultrasonic flow meter is equipped with a housing through which a liquid flows, and a pair of detection units disposed on opposite ends of the housing and including acoustic wave transmitting and receiving units capable of transmitting and receiving acoustic wave signals. Vibration generating mechanisms having vibration generating bodies arranged perpendicularly to the detection units are disposed on an outer circumferential side of the housing. In addition, when the flow rate of the liquid that flows through the housing is measured, the vibration generating bodies are energized and made to vibrate, such that gas bubbles, which adhere to cover members in contact with the liquid and that cover the acoustic wave transmitting and receiving units, are removed by the vibrations.

Abstract: A method of monitoring acoustic energy using distributed acoustic sensing. The method involves supplying a fluid flow at different pressures and sensing fluid flow characteristics in at least one location at each pressure. The data may be processed to provide a fluid resistance value related to a particular fluid flow at each location, collectively forming a fluid resistance index (FRI). The method may include following the initial fluid flow with a process flow, which may then be followed by another fluid flow. The flow characteristics of the latter fluid flow may be measured and compared with the initial fluid flow, providing a measure of the success of the process flow. In application, this method may be used to enhance downhole operations, including acid stimulation treatments.

Abstract: An ultrasonic flow rate measuring device includes a flow path, a partition plate that is inserted from an aperture to partition the flow path into plural sections, an ultrasound transmission body, plural ultrasonic transducers that are provided in positions facing a bottom plate such that an ultrasonic wave transmitted from one of the ultrasonic transducers through the ultrasound transmission body is reflected by the bottom plate and received by the other ultrasonic transducer, a measurement circuit that measures an ultrasonic propagation time between the plurality of the ultrasonic transducers; and a calculation circuit that obtains a flow rate of the target fluid based on a signal from the measurement circuit.

Abstract: A flowmeter has a one-piece conduit with an outer surface and an inner surface that define a wall thickness therebetween, and first and second transducers, where each transducer is disposed external of or integral with the one-piece conduit, in signal communication with an interior volume of the one-piece conduit, and relative to each other such that each transducer can send and receive an acoustic signal to the other transducer. The one-piece conduit includes a plurality of acoustic noise attenuating features integrally formed with at least one of the outer surface and the inner surface and disposed between the first and second transducers, each of the features being configured and oriented to disturb a propagation direction of a parasitic acoustic wave that will propagate in the wall of the one-piece conduit in response to activation of at least one of the transducers.

Abstract: A measuring tube, a measuring system and a method for determining and/or monitoring flow through a measuring tube, comprising a measuring tube, on which ultrasonic transducers are releasably placeable. The ultrasonic transducers transmit and/or receive ultrasonic signals, which pass through the measuring tube approximately coaxially to the measuring tube axis. At least one ultrasonic transducer comprises at least one tiltable clamp which can be locked into at least one elevation or depression located on the measuring tube.

Abstract: A method for relaying a radio signal between two points having an obstacle therebetween is described. The method includes maintaining an unmanned aerial vehicle (UAV) in an orientation with respect to the two points, the UAV having at least one passive reflective device having an elongated configuration thereon, transmitting a signal from one of the two points, the transmitted signal impinging the at least one passive reflective device, and receiving the signal at the other of the two points, the received signal being a signal reflected from the at least one passive reflective device.

Abstract: To find the propagation time of an ultrasonic wave, a difference occurs between the waveforms received upstream and downstream in a portion where the reception amplitude is comparatively large and it is prevented from being detected as an error of the propagation time. A reception signal is amplified in a reception unit 35 and reception point storage units 38 store the most recent reception point data in a plurality of storage sections in order until the signal level becomes a predetermined value (Vref). An average value of the two zero crossing points before and after the signal level becomes Vref can be adopted as a reception point, the propagation time with a small error of up and down offset, etc., is measured, and it is made possible to realize power saving operation by shortening the measurement time.

Abstract: A flowmeter for detecting fluid flow rates in a pipe includes a tube having a channel disposed in the pipe through which fluid in the pipe flows. The flowmeter includes an upstream transducer in contact with the pipe and positioned so plane waves generated by the upstream transducer propagates through the channel. The flowmeter includes a downstream transducer in contact with the pipe and positioned so plane waves generated by the downstream transducer propagate through the channel and are received by the upstream transducer which produces an upstream transducer signal. The downstream transducer receives the plane waves from the upstream transducer and provides a downstream transducer signal. The flowmeter includes a controller in communication with the upstream and downstream transducers which calculate fluid flow rate from the upstream transducer signal and the downstream transducer signal. A method for detecting fluid flow rates in a pipe.

Abstract: The present invention provides an acoustic flow meter assembly (2) for pipes or open channels, said assembly including a frame (24) with a predetermined geometry. The frame has at least one user accessible port (36-42) with the at least one user accessible port (36-42) adapted to receive an interchangeable cartridge (44) which contains at least one acoustic transducer (46) to measure fluid velocity through said frame (24).

Abstract: A measuring tube, a measuring system and a method for determining and/or monitoring flow through a measuring tube, comprising a measuring tube, on which ultrasonic transducers are releasably placeable. The ultrasonic transducers transmit and/or receive ultrasonic signals, which pass through the measuring tube approximately coaxially to the measuring tube axis. A connecting line between the centers of the ultrasonic transducers situated at an angle relative to the measuring tube axis and extends on a side of the measuring tube axis, on which the measuring tube outlet is located.

Abstract: A flow meter ultrasonically measures fluid velocity in a pipe and ultrasonically transmits fluid flow data along the pipe. An ultrasonic transducer used for fluid velocity measurement may optionally also be used for communication of flow data, and optionally, the ultrasonic frequency for fluid velocity measurement may be the same as the ultrasonic frequency for communication of flow data.

Abstract: A device and a method for determining a flow velocity of a fluid or a fluid component in a pipeline is described. The device comprises a transmitter adapted to be placed inside the pipeline and arranged to transmit an ultrasound signal into the fluid or fluid component in a first direction; a receiver adapted to be placed inside the pipeline and arranged to receive a dispersed ultrasound signal, generated by dispersion of the ultrasound signal by the fluid or the fluid component in a second direction, the second direction being different from the first direction, and to provide a receiver signal representing the dispersed ultrasound signal; and, a processing unit arranged to receive said receiver signal and to determine a frequency difference between the transmitted ultrasound signal and the dispersed ultrasound signal and determining the flow velocity of the fluid or the fluid component based on said difference.

Abstract: A flowmeter has a one-piece conduit with an outer surface and an inner surface that define a wall thickness therebetween, and first and second transducers, where each transducer is disposed external of or integral with the one-piece conduit, in signal communication with an interior volume of the one-piece conduit, and relative to each other such that each transducer can send and receive an acoustic signal to the other transducer. The one-piece conduit includes a plurality of acoustic noise attenuating features integrally formed with at least one of the outer surface and the inner surface and disposed between the first and second transducers, each of the features being configured and oriented to disturb a propagation direction of a parasitic acoustic wave that will propagate in the wall of the one-piece conduit in response to activation of at least one of the transducers.

Abstract: Systems and method for acoustic detection using flow sensors are provided. One system includes a flow conduit configured to allow fluid flow therethrough and a flow disrupter configured to impart a flow disturbance to the fluid flow. The system also includes at least one of a first sensor or a second sensor. The first sensor is disposed within the flow conduit at a first position, wherein the first sensor is responsive to first disturbances and configured to generate signals characteristic of the first disturbances. The second sensor is disposed within the flow conduit at a second position, wherein the second sensor is responsive to second disturbances and configured to generate signals characteristic of the second disturbances. The system additionally includes a processor operably coupled to the first and second sensors, wherein the processor is configured to distinguish between signals characteristic of the first and second disturbances.

Abstract: Apparatus and method for ultrasonic flow metering of viscous fluids. In one embodiment, an ultrasonic flow metering system includes an ultrasonic flow meter, a flow conditioner, and a reducer. The ultrasonic flow meter includes a pair of ultrasonic transducers arranged to exchange ultrasonic signals through a fluid stream flowing between the transducers. The flow conditioner is disposed upstream of the ultrasonic flow meter. The reducer is disposed between the flow conditioner and the ultrasonic flow meter to reduce the cross sectional area of the fluid stream flowing from the flow conditioner to the ultrasonic flow meter.

Abstract: An ultrasonic flow-meter of the present invention includes a partition plate which partitions a passage of a target fluid into a measurement passage and a non-measurement passage, a pair of ultrasonic transducers which is disposed in the measurement passage, a measuring unit which measures a propagation time of an ultrasonic wave between the pair of ultrasonic transducers, and a calculating unit which calculates a flow rate of the target fluid. Further, the calculating unit has a computing unit which computes at least one of a flow velocity and a flow rate of the target fluid in the measurement passage based on the propagation time and an estimating unit which estimates the flow rate of the target fluid in the passage based on the flow velocity or the flow rate in the measurement passage. As a result, an ultrasonic flow-meter which highly accurately measures a target fluid by using a simple configuration can be realized.

Abstract: A method of producing an ultrasonic flow meter having the steps of fabricating a tube made of a sound absorbing material. There is the step of machining in the tube a channel having a constant inner diameter through which fluid flows. There is a step of attaching the cylinder to the ultrasonic flow meter.

Abstract: A flow sensor includes a plurality of ultrasonic transceivers and signal processing circuitry. The transceivers are coupled to a portion of the outer surface of a duct, and each is configured to transmit ultrasonic waves into a fluid, receive ultrasonic waves, and supply sensor signals representative of the received ultrasonic waves. The signal processing circuitry is configured to supply separate excitation signals to each of the ultrasonic transceivers, receive the sensor signals supplied by each of the ultrasonic transceivers, and generate, in response to the sensor signals, a flow signal representative of fluid flow in the flow passage. Each of the excitation signals has a different phase, such that the ultrasonic waves transmitted by each of the ultrasonic transceivers at least selectively combine to propagate in an adjustable direction relative to the flow direction.

Abstract: The invention relates to an ultrasonic flow meter arranged to measure a flow rate of a liquid, the flow meter comprises a flow tube 2, optionally a measurement insert, and two or more ultrasonic transducers 8 which are arranged in transducer inserts 20 to be inserted into the flow tube through openings in the flow tube. The transducer inserts are formed monolithically with the housing as a part of the bottom of the housing. The transducer inserts are in a mount position inserted through the openings in the flow tube to extend into the flow passage so that the surface 15 of the transducer inserts protrude into the flow passage. In this manner, gas bubbles, such as air bubbles, released from the flowing liquid will not rest in front of the transducer insert irrespectively of the orientation of the flow meter in the pipe installation.

Abstract: A meter tube assembly for use with an ultrasonic flow meter is provided. The meter tube assembly includes a pipe spool having an extremely rough first section including an interior surface with a relative roughness (?/D) of 1% or greater. Fluid passing through the extremely rough section exhibits a flow profile that remains substantially constant over the range of Reynolds numbers. As such, ultrasonic flow meters can be simplified as they need not account for different Reynolds numbers.

Abstract: An ultrasonic measurement apparatus (10) for measuring the flow velocity of a fluid is provided which flows in a pipeline in a main flow direction, wherein the ultrasonic measurement apparatus (10) has an ultrasonic measurement zone (36) with at least a pair of ultrasonic transducers (38), an evaluation unit for determining the flow velocity from a propagation time difference of ultrasound transmitted and received with and against the flow, as well as a deflection unit, by means of which the fluid from the main flow direction is deflectable and suppliable to the ultrasonic measurement zone (36). In this respect the deflection unit (20, 26, 32) forms a loop.

Abstract: The present invention pertains to a flow conditioner for displacing and mixing fluid flow to minimize the effects of thermal gradients on the accuracy of a transit time ultrasonic flowmeter and defines an envelope in a cross sectional direction in a pipe having a first ramp adapted to be disposed in the pipe and extending from the outside of the envelope inward toward the center of the pipe in a downstream direction with respect to the fluid flow and forming an angle between 0° and 90° relative to the pipe's inner surface. The conditioner has a second ramp adapted to be disposed in the pipe and in juxtaposition with the first ramp, the second ramp extending from the outside of the envelope inward toward the center of the pipe in an upstream direction with respect to the fluid flow and forming an angle between 0° and 90° relative to the pipe's inner surface. An apparatus for determining fluid flow in a pipe having ultrasonic transducer sites. A method for determining fluid flow in a pipe.

Abstract: An ultrasound transducer (10) is provided having an oscillating body (12) for generating and/or receiving ultrasound and having a damping body (14) which has a first part body (16) of a first material arranged at a rear side of the oscillating body (16), said first material having an acoustic impedance matched to a material of the oscillating body (12), and which has a second part body (18) of a second material arranged at the first part body (16), said second material having a high acoustic damping. In this respect, the first part body (16) is conical and its base surface is arranged on the oscillating body (12).

Abstract: An in-medium monitoring system for monitoring material carried within a pipe. The system includes an acoustic device installed within the pipe that generates voltage signals indicative of changes in the material, such as flow rate or leaks, a hardware unit that includes a detector module and a communication module, a switch for switching the voltage signals to and communication signals from the hardware unit. The hardware unit and a power source are attached to the pipe. The acoustic device may be detector or a sensor. The communication module may communicate date through the sensor in the medium or outside of the pipe to a fixed network. The hardware unit may include a log detection amplifier for generating an amplified pulsed output signal without voltage gain and without significantly adding noise.

Abstract: Acoustic flow rate meter for the noninvasive determination of the flow or the flow rate in electrically conductive objects through which media flow, in particular pipes or pipelines, having an excitation transducer for generating at least one ultrasonic wave in the object, which is coupled into the medium as a longitudinal wave on an inner side of the object oriented toward the medium, and having a receiving transducer for the detection of an ultrasonic signal in the object, wherein the ultrasonic signal at least partially results due to the longitudinal wave, wherein the excitation transducer is implemented as a high-frequency induction coil, while omitting an acoustic coupling of the excitation transducer with the surface of the object, to generate a varying magnetic field in a surface-proximal region of the object, which is metallic in particular, and the ultrasonic wave is generated by interaction of the varying magnetic field with a static or quasi-static magnetic field in this region.

Abstract: An ultrasonic signal coupling assembly including ultrasonic transducers attached to one or more ultrasonic couplers configured to be coupled to an exterior surface of a pipe. A height of the ultrasonic coupler or couplers is greater than a thickness of the pipe by a factor of about five or more, and a length of the ultrasonic coupler or couplers is greater than the height of the ultrasonic coupler or couplers.

Abstract: An ultrasonic signal coupler includes a pipe having a first ultrasonic waveguide and a second ultrasonic waveguide penetrating the pipe so that ultrasonic transducers attached to ends of the ultrasonic waveguides communicate ultrasonic signals through the ultrasonic waveguides directly through a fluid traveling through the pipe.

Abstract: An ultrasonic flow meter permitting easy insertion and removal of a tube or conduit. A partial ring transducer or partial cylinder transducer is used to permit easy insertion and removal of a flexible tube in an ultrasonic flow meter for measuring fluid flow. In another embodiment a split ring or split cylinder transducer is used to facilitate easy removal and insertion of a tube or conduit in which fluid flow is to be measured. In another embodiment a clamping system is used to securely hold and couple a tube or conduit within the ultrasonic flow meter system. The present invention is conveniently adapted to hold flexible tubes and in particular disposable flexible tubes often used in the medical industry.

Abstract: Apparatus and method for monitoring operation of an ultrasonic flow meter. In one embodiment, an ultrasonic flow metering system includes a passage for fluid flow, an ultrasonic flow meter, and a condition monitor. The ultrasonic flow meter is configured to measure transit time of an ultrasonic signal through the fluid flowing in the passage. The condition monitor is coupled to the ultrasonic flow meter and is configured to monitor a parameter of operation of the ultrasonic meter, and to acquire a plurality of values of the parameter over time. The condition monitor is also configured to compute, for each of the acquired values, a difference between the acquired value and a predetermined reference, and to arrange the differences in time sequence.

Abstract: Apparatus and methods for monitoring operation of an ultrasonic flow meter. In one embodiment, an ultrasonic flow metering system includes a passage for fluid flow, an ultrasonic flow meter, and a condition monitor. The ultrasonic flow meter is configured to measure transit time of an ultrasonic signal through the fluid flowing in the passage. The condition monitor is coupled to the ultrasonic flow meter and is configured to monitor a parameter of ultrasonic meter operation with respect to Reynolds number. The condition monitor is further configured to determine whether a value of the parameter at a Reynolds number of the fluid flowing in the passage at a time associated with the value is within a predetermined range of values for the parameter at the Reynolds number.

Abstract: A fluid flow meter estimates the velocity of water or another fluid flowing through pipe by comparing measurements of the water velocity to one or more pre-determined templates. The fluid flow meter may collect measurement signals from one or more flow sensors, estimate the fluid velocity or flow rate by comparing the measurement signals to the template, and either store the comparison results in local memory, transmit the results to a remote memory or server, or both. In some embodiments, the fluid flow meter transmits the results to a server via a wireless interface. The transducers and processing system can be powered by a battery, a power line, or, for manifolds installed outdoors, a solar cell. Example transducers and processing systems may also have a passive wake-up feature for power reduction; that is, they may only draw power when water or another fluid flows through the pipe.

Abstract: A method of estimating the time of flight of a burst signal includes: receiving the burst signal; determining the slope of the phase characteristic of the Fourier transform of the received burst signal; and estimating the time-of-flight of the burst signal from the slope of the phase characteristic of the Fourier transform of the received burst signal.

Abstract: A flow sensor includes a plurality of ultrasonic transceivers and signal processing circuitry. The transceivers are coupled to a portion of the outer surface of a duct, and each is configured to transmit ultrasonic waves into a fluid, receive ultrasonic waves, and supply sensor signals representative of the received ultrasonic waves. The signal processing circuitry is configured to supply separate excitation signals to each of the ultrasonic transceivers, receive the sensor signals supplied by each of the ultrasonic transceivers, and generate, in response to the sensor signals, a flow signal representative of fluid flow in the flow passage. Each of the excitation signals has a different phase, such that the ultrasonic waves transmitted by each of the ultrasonic transceivers at least selectively combine to propagate in an adjustable direction relative to the flow direction.

Abstract: An ultrasonic flow rate measurement device includes a measurement channel, through which a fluid to be measured flows; and a sensor fixing casing having openings formed in the measurement channel and sensor fixing cavities communicating with the openings. Moreover, the ultrasonic flow rate measurement device includes a pair of ultrasonic sensors contained in the sensor fixing cavities, for measuring the flow rate of the fluid to be measured; and a flow rate measuring unit for detecting the flow rate based on an ultrasonic wave propagation time between the pair of ultrasonic sensors. Furthermore, the ultrasonic flow rate measurement device includes a suppressing member formed at each of the openings, for suppressing the fluid to be measured from intruding into each of the sensor fixing cavities, wherein the suppressing member is molded integrally with the sensor fixing casing.

Abstract: An ultrasonic transducer for a pipe includes an ultrasonic source which produces plane waves. The transducer includes a housing having a face at least a portion of which is curved through which the plane waves produced from the source disposed in the housing are emitted and directed outward towards the pipe's interior wall so a full cross-section of the pipe's interior can be measured. A flow meter for detecting fluid flow rates in a pipe. A method for detecting fluid flow rates in a pipe.