Abstract: A method for determining the time of flight, preferably the absolute time of flight, of an ultrasound signal in a flowing medium, includes using an ultrasound emitter to generate an ultrasound signal provided with a marker. The ultrasound signal is transmitted through the flowing medium to an ultrasound receiver, and the location of the marker is used in order to determine the time of flight of the ultrasound signal. The period duration of at least one selected period of the reception signal is measured to determine the location of the marker. An ultrasonic flow meter which can be operated according to the method is also provided.

Abstract: A convertible housing assembly for a particle sensor includes an integral housing and at least one guide element. The integral housing includes a longitudinal bore, a first intersecting bore, and a second intersecting the bore. The longitudinal bore extends from a first end surface of the integral housing to a second end surface of the integral housing. The first intersecting bore extends from a bottom surface of the integral housing and intersects with the longitudinal bore. The second intersecting bore extends from the bottom surface of the integral housing and intersects with the longitudinal bore. The at least one guide element is secured within the longitudinal bore to reduce turbulence of a fluid flowing therethrough.

Abstract: An inspection device for an ultrasound flow meter is provided that has an inspection chamber having a fluid at a flow velocity of zero and having a first installation station for a first ultrasonic transducer and having a second installation station for a second ultrasonic transducer of the ultrasound flow meter so that the ultrasonic transducers are aligned toward one another in the installed state and span an ultrasound measurement path through the inspection chamber on the connection line. The invention further relates to a method of inspecting and/or calibrating an ultrasound flow meter.

Abstract: Embodiments include a novel, easy to install, non-intrusive, ultrasonic water flow meter with a self-calibrating three-piezoelectric transducer configuration attached externally to a water pipe, that allows for accurate measurement of water flow, and can provide the flow data to a remote system for billing and further analysis. The water flow data can further be analyzed for water consumption by individual fixtures, in support of conservation and usage management efforts.

Abstract: An ultrasonic measuring device for the measurement of a flow of a fluid, includes a measuring tube, a first chamber and a second chamber. The measuring tube has a central axis, which defines a flow direction for the fluid; The first chamber has a first ultrasonic transducer arranged therein. The second chamber has a second ultrasonic transducer arranged therein. The measuring tube includes an inlet and an outlet for the fluid. The first ultrasonic transducer and the second ultrasonic transducer bound a rectilinear measuring section for the fluid, the first chamber and the second chamber being configured and arranged such that the fluid is capable of flowing around each of them. The first ultrasonic transducer and the second ultrasonic transducer are arranged such that the measuring section extends in the flow direction.

Abstract: A magnetic-inductive flowmeter for determining the flow of a medium, having a measuring tube for guiding the medium and having two electrodes for tapping a measuring voltage induced in the medium, wherein the measuring tube has an inflow section, a measuring section and an outflow section arranged one after the other in the flow direction of the medium, the inflow section having a cross section which decreases in the flow direction, the measuring section having a constant cross section and being symmetrical with respect to a measuring section symmetry plane which runs parallel to the longitudinal axis of the measuring tube, and the outflow section having a cross section which increases in the flow direction and is formed at least partially asymmetrically with respect to the measuring section symmetry plane in order to increase measuring accuracy.

Abstract: A sensor apparatus is provided for measuring within a region of a conduit for guiding a flow. The apparatus includes a transducer arrangement disposed at least partially around an external surface of a wall of the conduit and having one or more driver elements for exciting in operation a helical acoustic wave propagation within the wall of the conduit for leaking acoustical energy from the helical acoustic wave propagation over an extensive area of the wall of the conduit for stimulating waves in chordal paths within the flow, wherein the waves in the choral paths within the flow reenter the wall of the conduit to propagate further as a guided helical wave. The transducer arrangement includes one or more sensors for receiving a re-entered portion of the acoustic wave propagation along the paths within the flow which interacts with the flow and includes information characterizing properties of the flow.

Abstract: A method of measuring a flow rate of a fluid flowing along a path, the method comprising: transmitting successive pairs of periodic signals through the fluid, the respective signals of each pair being transmitted in opposite directions along, and from opposite ends of, the path; determining a difference in propagation times of each signal of each pair along the path; and determining a flow rate of fluid along the path based on the difference in propagation times of the signals of each pair along the path; wherein a phase of each signal is altered with respect to a phase of at least one other signal transmitted along the path.

Abstract: The present invention relates to a flow rate measuring method comprising: establishing a database which includes a plurality of flow profiles; measuring the flow in a flow field using a plurality of transducers wherein in between every two transducers there exists an acoustic path which indicates the flow speed of the flow between the two transducers, and a feature map can be derived from the flow speeds; comparing the feature map with the database; selecting a matching flow profile from the flow profiles wherein the matching flow profile has a plurality of weighting functions corresponding to the acoustic paths; and calibrating the flow speed using the weighting functions.

Abstract: Methods and apparatus for identifying media are described. Example methods disclosed herein include presenting a graphical enable button via a display of a media presentation device, the graphical enable button, when selected, is to enable monitoring functionality implemented by the media presentation device, the monitoring functionality to monitor media presented by the media presentation device, the monitoring functionality to be disabled by default. Disclosed example methods also include detecting a first user input corresponding to selection of the graphical enable button and, in response to detection of the first user input: (i) enabling the monitoring functionality implemented by the media presentation device, and (ii) transmitting, via a network interface, information to a remote monitoring entity.

Abstract: An ultrasonic measuring device for measuring a fluid flowing in a pipe includes a housing and transducers. The housing receives and fixes the pipe, so that the fluid can flow through a central recess in a flow direction. The ultrasonic transducers emit and receive ultrasonic signals. Two first ultrasonic transducers are arranged laterally on a first side of the central recess, and two second ultrasonic transducers are arranged on a second side of the central recess. The second side is opposed to the first side, so that the recess is located between the first and the second ultrasonic transducers, and the ultrasonic transducers are arranged and aligned so that one of the first ultrasonic transducers emits a first measuring signal to one of the second ultrasonic transducers obliquely to the flow direction and receive a second measuring signal emitted by the second ultrasonic transducer obliquely to the flow direction.

Abstract: The present disclosure describes an ultrasonic flowmeter including: a measuring tube with a measuring tube wall and at least one pair of housings extending to an outer side of the measuring tube wall; a pair of ultrasonic transducers, each with a transducing element for generating and/or sensing ultrasonic pulses and a transducer body, wherein each of the housings is arranged to house one of the transducers, and wherein the housings have an inner first diameter; wherein transducer body includes a circumferential surface, and wherein the transducer body includes an end face, wherein the end face has a second diameter, and wherein the transducer includes at least one first protrusion protruding from the circumferential surface into a gap between the transducer body and the housing.

Abstract: A fluid meter has a measuring tube which has a fluid channel allowing a fluid (F) to flow through and which has a measuring section in which at least one area of a measuring tube wall is formed as a waveguide for surface acoustic waves, which forms an interface with the fluid (F), and at least one transmitter for exciting acoustic waves in the waveguide as well as at least one receiver for receiving acoustic waves from the waveguide, wherein acoustic waves excited by the transmitter can propagate through the fluid (F) as a bulk wave (V) and the bulk wave (V) has at least one reflection point (IP) on the measuring tube wall. The measuring tube wall has a first wall thickness (T1) in the area of the transmitter and in the area of the receiver and has a second wall thickness (T2) which differs from the first wall thickness (T1) in the area of all reflection points (IP) of the bulk wave (V).

Abstract: In an apparatus and method for measuring air flow in a duct, e.g. in a ventilation duct, the apparatus includes a sensor fittable into connection with the duct at a certain distance from an interference source, the sensor including an ultrasound transmitter and at least two ultrasound receivers, and a control unit to which the ultrasound transmitter and ultrasound receivers are connectable. The control unit is adapted to measure the phase difference of the ultrasound signal received at the same moment in time by at least two ultrasound receivers fitted into connection with the duct and, based on the measured phase difference, to determine the flow velocity and/or flow direction of the air. The control unit is adapted to compensate the determined flow velocity and/or flow direction of the air with a coefficient that is formed on the basis of the diameter of the duct, the type of interference source and the distance between the sensor and the interference source.

Abstract: Disclosed is a flow meter with at least two measuring sensors, preferably ultrasonic sensors, spaced apart from each other, wherein the coupling of the measuring signals into and out of a fluid is performed via a coupling element According to the disclosure, the measuring channel is formed with an approximately oval or trapezoid cross-section.

Abstract: A measuring device for determining a fluid variable relating to a fluid or fluid flow includes a control device, a measuring tube receiving the fluid or fluid flow, and oscillation transducers spaced apart on the measuring tube. At least one oscillation transducer is drivable by the control device to excite a wave conducted through at least one side wall of the measuring tube, the conducted wave exciting compression oscillations of the fluid conducted through the fluid to the other oscillation transducer and recorded there by the control device to determine measurement data. The fluid variable can be determined by the control device as a function of the measurement data. At least one further side wall of the measuring tube has at least one recess extending in a flow direction and increasing a flow cross section of the measuring tube. A method for determining a fluid variable is also provided.

Abstract: Disclosed is a flow meter with at least two measuring sensors, preferably ultrasonic sensors, spaced apart from each other, wherein the coupling of the measuring signals into and out of a fluid is performed via a coupling element which is inserted flush into a circumferential wall of a measuring channel.

Abstract: To provide a clamp-on type ultrasonic flow sensor capable of calculating a flow rate of fluid flowing in a pipe. An elastic couplant 114 is supported on a pipe P by a clamp member 130 such that a pipe contact section T1 is in contact with the pipe P. The pipe contact section T1 is surrounded by a damping material 116 between the clamp member 130 and the pipe. An elastic couplant 124 is supported on the pipe by a clamp member 140 such that a pipe contact section T2 is in contact with the pipe. The pipe contact section T2 is surrounded by a damping material 126 between the clamp member 140 and the pipe. The clamp members 130 and 140 are coupled to each other to sandwich the pipe in a state in which the clamp members 130 and 140 respectively press the damping materials 116 and 126.

Abstract: A reflector clamping member (RCM) for fixating an ultrasound reflector (REF) to a flow conduit insert (FCI) of an ultrasonic flow meter (UFM) is disclosed, the reflector clamping member (RCM) comprising a fixation portion (FXN) for fixating the reflector clamping member (RCM) to the flow conduit insert (FCI) and a flexible portion (FLX) for contacting the ultrasound reflector (REF), wherein the flexible portion (FLX) is adapted for supporting at least one side of the ultrasound reflector (REF) so as to clamp the ultrasound reflector (REF) between the flexible portion (FLX) and the flow conduit insert (FCI) when the reflector clamping member (RCM), the ultrasound reflector (REF), and the flow conduit insert (FCI) are assembled. Also, a flow conduit insert assembly (ASY) comprising such reflector clamping member (RCM), an ultrasonic flow meter (UFM) comprising such reflector clamping member (RCM), and a method of fixating an ultrasound reflector (REF) to a flow conduit insert (FCI) are disclosed.

Abstract: An apparatus for determining fluid flow in a pipe including a transit time chordal ultrasonic meter that eliminates dependence of meter factor on Reynolds number for measuring the flow through the pipe. The meter having a bore through which the fluid flows and a plurality of cavities with transducers disposed in the cavities which produce ultrasonic pulses that pass through the fluid and define multiple chords. The fluid velocity measured by clocking the pulses' time traveling diagonally upstream and downstream between pairs of the transducers. The transducers in the cavities isolated from the fluid flow in the bore by each cavity of the cavities having a liner which separates each cavity from the bore. A method for determining fluid flow in a pipe.

Abstract: A system for measuring flow rate within a volume includes one or more transmission devices that transmit one or more signals through fluid contained within the volume. The volume may be bounded, at least in part, by an outer structure and by an object at least partially contained within the outer structure. A transmission device located at a first location of the outer structure transmits a first signal to a second location of the outer structure. A second signal is transmitted through the fluid from the second location to a third location of the outer structure. The flow rate of the fluid within the volume may be determined based, at least in part, on the time of flight of both the first signal and the second signal.

Abstract: A system and method for calculation of flow rate comprising at least two ultrasonic sensors, ultrasonic transmit receive device, and signal processing device. At least two ultrasonic sensors are installed on the pipe where the fluid is flowing through, and at least two ultrasonic sensors contain different ultrasonic beam paths, further, the ultrasonic beam paths of at least two ultrasonic sensors contain the overlap area. The ultrasonic transmit and receive device is used to actuate at least two ultrasonic sensors, and is used to transmit one or multiple ultrasonic signals to pipes via one or multiple of at least two ultrasonic sensors, further, to receive ultrasonic signal via at least two ultrasonic sensors. The signal processing device is used to process the ultrasonic signal received, further, to calculate the flow rate of the fluid precisely.

Abstract: According to some embodiments of the present invention there is provided a method of using an earphone output speaker as a microphone for a phone call between two and/or more participants, or for measuring biometric data of a user. The method may comprise playing a received signal to an electro-acoustic output transducer of an earphone. The method may comprise instructing an audio processing circuit of a local client terminal to record an audio signal from the same electro-acoustic output transducer. The method may comprise calculating a voice signal and/or a biometric measurement based on a function combining the recorded audio signal, the received signal, and filtration coefficients, using a processing unit of the local client terminal. The method may comprise sending the voice signal and/or a biometric measurement through an output interface of the local client terminal.

Abstract: An undershot gate system controls flow of liquid through an open channel or pipe. The system includes a gate leaf adapted to be raised and lowered by a control to allow flow of liquid along the open channel or pipe. The gate leaf has a flow diverter at an end of the gate leaf to guide liquid under the gate leaf and through an opening when the gate leaf is in an open position.

Abstract: The present invention relates to flow measurement, and more particularly, to a system for measuring a flow rate by three-dimensionally crossing a plurality of sidings each other within a conduit. An ultrasonic flow measurement system according to the present invention determines a flow central part of fluid by three-dimensionally crossing the plurality of sidings each other within the conduit in three dimensions and calculates a flow rate flowing in the conduit, meeting the flow central part, thereby more accurately measuring the flow rate than the existing method.

Abstract: A measuring tube for a flow measuring device, wherein the measuring tube has a measuring tube axis A and a measuring tube wall. The measuring tube has a branch with a branch axis B and a wall of the branch, wherein the wall of the branch is arranged on the measuring tube wall, and the wall of the branch is connected with the measuring tube wall by a welded joint. In the transitional region between the wall of the branch and the measuring tube wall there is a specially embodied thickening of the material, which is either part of the wall of the branch or part of the measuring tube wall.

Abstract: An ultrasonic flow meter including a meter housing, a flow tube with an inner flow channel for a fluid to be measured, and ultrasound reflectors, the meter housing has two transducer recesses, an ultrasound transducer positioned in the first transducer recess, and a second ultrasound transducer positioned in the second transducer recess. The transducer recesses each has slanted bottom walls, with the ultrasound transducers abutted against the slanted bottom walls of the recesses.

Abstract: A flow element for an ultrasonic flowmeter having a plurality of transducers for analyzing fluid flow in a pipe. The flow element includes a housing having a bore with an internal diameter and a surface through which fluid flows and a plurality of cavities each of which has an opening in the surface. Each of the cavities has one of the plurality of transducers disposed in it. The flow element includes a liner that covers the openings of the cavities which prevents fluid flowing through the bore from entering the cavities.

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: The present invention relates to a method and a device for fetal cardiac monitoring. For improving ultrasonic monitoring, the number of periodic signals, such as signals caused by the fetus and the mother, is assessed and the time window of the signal demodulation is adapted if more than one periodic signal is assessed.

Abstract: An ultrasonic, flow measuring device, including a measuring tube a transmitter a receiver and at least a first reflection surface. An acoustic signal incident on a first reflection surface and an acoustic signal reflected on the first reflection surface travel, in each case, along a straight subsection of the first signal path. The transmitter, the receiver and the first reflection surface are so oriented with respect to one another and arranged in or on the measuring tube that the acoustic signal on the first signal path from the first transmitter to the first receiver is so reflected on the first reflection surface that the sum of all lengths of all subsections as projected on a measuring tube axis, extending in a first plane parallel to the measuring tube axis, and having a predetermined separation other than zero from the measuring tube axis has a predetermined value different from zero.

Abstract: An edge of a piezoelectric disk transducer is biased into an external wall of a flow passage by a spring. The disk is then driven at a radial mode resonant frequency to project acoustic energy into fluid flowing in the passage. This arrangement is compatible with several types of fluid flow sensors such as transit time, Doppler, and vortex shedding flow meters.

Abstract: A multimode flow meter can use both the time-of-transit of upstream and downstream ultrasonic signals and time for transmission of downstream-only signals to determine a flow velocity of a medium flowing through a conduit. Based on factors, such as previously computed flow velocity and signal-to-noise ratio of the upstream signal, a mode of operation may be switched and only the time for transmission of the downstream signals may be used to determine flow velocity. The multimode flow meter can compute cross-flow to reduce its effect on the determination of flow velocity.

Abstract: A measurement control section of a flow meter device causes a measurement block dividing section to divide a sampling cycle Tc into three or more, for example, four measurement blocks Tb of an equal length and causes the flow measuring section to measure the flow of a fluid in each of the measurement blocks Tb. A flow calculating section of the flow measuring section calculates an average value of flow values obtained in all of the measurement blocks in each sampling cycle Tc, as a flow value in each sampling cycle Tc. This configuration allows a flow meter device which employs an inverse transit time difference method, such as an estimation gas meter, to more effectively lessen the influence of a pulsation and to perform flow measurement with higher accuracy.

Abstract: An apparatus for measuring the mass fractions of water and oil in a flowing mixture of oil and water through a pipe includes a sensor portion that measures sound velocity and temperature of the flowing oil water mixture at a first time and at a second time. The apparatus includes a temperature changer in thermal communication with the flowing fluid which changes the temperature of the flowing oil water mixture by a measurable amount between the first time and the second time. A method for measuring water mass fraction in a flowing mixture of oil and water through a pipe includes the steps of measuring sound velocity and temperature of the flowing oil water mixture at a first time with a sensor portion. There is the step of changing the temperature of the flowing oil water mixture by a measurable amount with a temperature changer in thermal communication with the flowing fluid.

Abstract: The application describes techniques for monitoring the rate of flow of fluid in a conduit (205) using fibre optic distributed acoustic sensing which are especially applicable to flow in oil and gas wells. The techniques also allow for calibration of the position of the channels of a fibre optic distributed acoustic sensor arranged along a fluid carrying conduit. The techniques comprise introducing a first acoustic stimulus (303) travelling in one direction and a second acoustic stimulus (304) travelling in the opposite direction. Flow of the fluid (v) results in a difference in the propagation velocity of the two acoustic stimuli. The first and second acoustic stimuli create a standing wave and the beat effect due to the flow induced wavelength variation is detected and used to determine flow rate. The acoustic stimulus may be introduced to travel through the conduit to provide the first stimulus and to reflect from the end of the conduit and travel back as the second acoustic stimulus.

Abstract: Provided is an ultrasonic flow meter capable of detecting a flow rate using measurement flow channel including layered flow channels and a pair of ultrasonic sensors and disposed on a wall surface on the same side of measurement flow channel so as to form a propagation path of ultrasonic waves utilizing reflection on flow channel inner wall surface on an opposing side, and control rod as fluid control means is disposed on an upstream side of separation plates that form a multilayer section.

Abstract: Switching a transmitting and receiving direction of two transducers (2,3) in the forward and the reverse direction, a time differential memory part (17b) storing a propagation time differential every K times a unit measurement process being executed, the propagation time differential being a differential between a propagation time of the ultrasonic wave signal in a forward direction and in a reverse direction, a flow rate calculating part (15) calculating a flow rate of a passing fluid based on a lump sum of propagation times in both the forward and the reverse directions obtained at least every K times of a unit measurement process being executed, an estimating part (18) estimating a change in a momentary flow rate of the fluid based on the time differential obtained every K times of the unit measurement process being executed and storing thereof in a time differential memory part (17b), thus obtaining an accurate flow rate and detecting the change in the momentary flow rate.

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 transducer includes a piezoelectric element that is attached to a sonic lens, a support ring that holds the piezoelectric element, a flange, and a spoke. One end of the spoke is connected to the support ring and an opposing end of the spoke is connected to an inner surface of the flange. The sonic lens may be plastic film that coats the piezoelectric element.

Abstract: A device (10) for measuring the flow rate of a fluid flowing in a pipe, especially for a transaction between a hydrocarbon supplier and a hydrocarbon purchaser is provided. The device (10) has a cylindrical body (11) to be interposed between two sections of the pipe. Ultrasound-beam transducers (15) are mounted on the main body (11) and intended to measure at least a rate of movement of the fluid stream as this flows through the device (10). At least one converter converts the signals emitted by the transducers into a flow rate signal. The transducers (15) are mounted and uniformly distributed on two coaxial parallel rings (12, 13). The transducers (15) of a first ring (12) are angularly offset relative to the transducers of the second ring (13).

Abstract: The invention relates to a method of measuring a gas flow velocity using an ultrasonic gas flow meter, wherein said ultrasonic gas flow meter includes a horizontal piping through which gas can flow in a flow direction and which has a central axis, at least one pair of measurement paths of equal length spaced apart, extending parallel to one another in separate horizontal planes and inclined to said flow direction, wherein each horizontal plane of a pair of measurement paths is vertically offset by an equal predefined distance from said central axis, wherein an ultrasonic transducer is arranged at each end of said measurement path and each ultrasonic transducer is adapted to selectively act as an ultrasonic transmitter and an ultrasonic receiver, the method comprising the steps of measuring a flow velocity of said gas in a measurement path arranged in an upper region of said piping, measuring a flow velocity of said gas in a measurement path arranged in a lower region of said piping and using the results of th

Abstract: A method and apparatus is disclosed that guides a user through a sequence of steps that will allow the user to complete a predefined task using the flow meter. The steps include: selecting a predefined task, displaying a sequence of steps that directs the user through a process for using the Coriolis flow meter to complete the predefined task, and operating the Coriolis flow meter in response to the sequence of steps to complete the predefined task.

Abstract: An ultrasonic measuring unit and a method for detecting ultrasonic signal run-times, in which the ultrasonic measuring unit has two ultrasonic transducers for coupling ultrasonic signals into a flowing medium. Analysis electronics are provided to be accommodated on or in a flow tube, in which a gaseous medium such as circulating air flows. A probe unit is accommodated in the flow tube, the probe unit being assigned a temperature probe having a flow around it, whose measured value is used for correcting a temperature signal detected by ultrasound.

Abstract: A flow measurement system and method uses enhanced phase detection based on a ratio of amplitudes of summations of two oppositely propagating acoustic signals. A need for direct time measurement and extensive difference calculation is consequently avoided so that in some implementations compact, simple, low power analog circuitry can be used.

Abstract: A method and apparatus is disclosed that guides a user through a sequence of steps that will allow the user to complete a predefined task using the flow meter. The steps include: selecting a predefined task, displaying a sequence of steps that directs the user through a process for using the Coriolis flow meter to complete the predefined task, and operating the Coriolis flow meter in response to the sequence of steps to complete the predefined task.

Abstract: A transformer board is disclosed. In some embodiments, the transformer board includes a base, a circuit board, a transformer having a first and second winding, a first and a second connector, a ribbon cable and a nonconductive fill material. The base has a recess within which the circuit board is positioned. The transformer is mechanically coupled to the circuit board. The first connector is configured to electrically couple to transducers within a pressure boundary of an ultrasonic flow meter and is electrically coupled to the second winding of the transformer. The ribbon cable is electrically coupled between the first winding of the transformer and the second connector. The nonconductive fill material is contained by the recess and encases the circuit board, the transformer, the coupling of the first connector to the second winding of the transformer, and the coupling of the ribbon cable to the first winding of the transformer.

Abstract: An ultrasonic flowmeter with a measuring tube through which flows a medium and which, viewed in cross section, has a split circumference forming two halves with two ultrasonic converter pairs, each with an associated ultrasound reflector. The converters of each pair are mounted on a common circumferential half in a mutually offset position as viewed in the longitudinal direction of the tube, while the reflector for each pair is positioned on the other, opposite circumferential half in the longitudinal direction of the measuring tube between the two converters, so that an ultrasound signal emitted by one converter of a pair travels along a V-shaped signal path via the reflector of the associated pair to the other converter of that pair. The first pair and the second reflector are positioned on one circumferential half of the tube while the second pair and the first reflector are positioned on the other, opposite circumferential half of the tube.

Abstract: Acoustic flow meter with dual flow measurements. At least some of the illustrative embodiments are flow meters comprising a spool piece that defines a central passage, a first plurality of transducer pairs mechanically coupled to the spool piece, a second plurality of transducer pairs mechanically coupled to the spool piece, and meter electronics electrically coupled to the first and second plurality of transducer pairs (the meter electronics configured to determine a first value indicative of fluid flow through the central passage, the first value determined using only signals of the first plurality of transducer pairs). The meter electronics further configured to determine a second value indicative of fluid flow through the central passage, the second value determined using only signals of the second plurality of transducer pairs.

Abstract: A time-of-flight flow meter that is particularly useful for measuring the flow of gases, such as steam, uses a spark gap periodically energized with an electrical pulse to generate an acoustic pulse. The pulse is detected by upstream and downstream acoustic detectors that may be capacitive transducers having flexible plates wetted on both sides by the fluid so that no external venting is required. The acoustic detectors may be electrically heated to avoid condensation effects. In some cases the interior of the pipe or other conduit is shaped near the source so as to define acoustic beams aimed at the detectors and so as to concentrate the received acoustic energy on the detectors.