Abstract: A system and method to detect and quantify integration errors in a transit time ultrasonic flow meter uses dissimilar integration methods or schemes employed simultaneously. In a preferred embodiment, a number of chordal paths are arranged in a single meter body such that at least two dissimilar chordal integration schemes can be used to determine the flow rate. At least one of the chordal paths is common to both integration schemes. The total number of chordal paths needed in any chordal measurement plane is less than the sum of the chordal paths used in each of the integration schemes (as is the sum of the planes), thereby reducing hardware requirements.

Abstract: An ultrasonic flow meter includes a meter housing, a first ultrasound transducer, a second ultrasound transducer, an electronic control arrangement for operating the ultrasonic flow meter, and a connection arrangement being arranged between the electronic control arrangement and the ultrasound transducers. The connection arrangement includes an electrically insulating support arrangement, and a set of elastic connectors for electrically connecting the electronic control arrangement with the first and second ultrasound transducers. The insulating support arrangement mechanically fixates the set of elastic connectors and maintains electrical separation between the set of elastic connectors.

Abstract: A measurement device includes a transmitter configured to transmit an interrogation signal. The measurement device also includes a receiver configured to receive the interrogation signal that has been reflected within a container. The received reflected interrogation signal corresponds to a fill level of the container. A protective barrier covers at least the transmitter or the receiver. If the protective barrier covers the transmitter, the transmitter transmits the interrogation signal through the protective barrier and the transmitter and the protective barrier are separated by a gap.

Abstract: A self-checking ultrasonic flow meter for measuring fluid flow in a conduit which includes a plurality of transducers engaged with the conduit. The flow meter includes a signal processor in electrical communication with the transducers which produces a measurement of flow rate and an associated estimate of uncertainty due to changes that have affected the accuracy of the measured flow rate. The transducers form multiple transducer pairs positioned to form acoustic transmission paths that are co-located in two or more chordal measurement planes. A plurality of axial velocity measurements are made in each chordal plane. A method for measuring fluid flow in a conduit with an ultrasonic flow meter.

Abstract: A method for operating a flowmeter for measuring the flow of a flowing medium through a pipe, wherein the flowmeter has a measuring unit for determining individual measured values of the flow and an error unit for determining the measurement uncertainty of the individual measured values. Determination of the individual measured values is carried out using a measuring frequency. A method for operating a flowmeter, which improves the quality of measurement is achieved in that a present measurement uncertainty is determined for each individual measured value by the error unit and by the measurement uncertainties from static and dynamic error sources being linked to one another by error propagation for determining the present measurement uncertainty.

Abstract: An ultrasonic flowmeter capable of increasing the amplitude of, and the receiving sensitivity for, an excited signal is provided. The ultrasonic flowmeter according to the present invention includes two or more ultrasonic transducers on a transmission side and two or more ultrasonic transducers on a receiving side, located as being away from each other on an outer surface of a tube having a fluid flowing therein. The two or more ultrasonic transducers located on the transmission side are driven so as to press the tube at substantially the same pressure to increase an amplitude of an ultrasonic wave. The ultrasonic flowmeter according to the present invention includes adjustment members converting an ultrasonic signal into an ultrasonic signal suitable to measurement between the tube and the ultrasonic transducers. The adjustment members each have a curved surface or a groove at a surface thereof contacting the tube.

Abstract: A method for measuring fluid flow within a fluid flow pipe includes partitioning a fluid flow within a pipeline with a nozzle bank, wherein a predetermined number of stepped nozzles is open; measuring the fluid flow in at least one partitioned fluid stream with at least one mass flow device; and calculating a total fluid flow within the pipeline. The nozzle bank includes a plurality of nozzles, each nozzle having a single step at about 1 throat diameter from an inlet plane of the nozzle, wherein the single step is an increase corresponding to about 10% of the throat diameter and has a length of about throat diameter/2.

Abstract: To position first and second sensor units easily at adequate positions simply by an operation for fixing a fitting to given piping. A first fitting for a first sensor unit and a second fitting for a second sensor unit are provided. The first and second fittings include a pair of arm portions configured to regulate relative position between the first sensor unit and the second sensor unit in a circumferential direction of the piping, and a guide portion formed at least on the arm portions, and configured to guide relative positioning between the first fitting and the second fitting in an axial direction of the piping according to a diameter of the piping.

Abstract: A measurement unit includes a fluid inlet to let a fluid flow in, a fluid outlet to let the fluid flow out, and a single flow path connecting the fluid inlet with the fluid outlet. The measurement unit further includes a plurality of partition boards and a measuring instrument. The plurality of partition boards are disposed along a current of the fluid and between facing side surfaces of the flow path. The plurality of partition boards define M flow path segments (where M is an integer of 2 or greater) between the facing side surfaces. The measuring instrument measures a flow rate of the fluid flowing through N successively adjacent flow path segments (where N is an integer of 1 or greater and less than M).

Abstract: The present disclosure relates to sensors and the teachings may be applied to a method and a corresponding apparatus for determining a concentration of a constituent of a fluid mixture in a fluid chamber. A method may include sending and receiving a first sound signal; sending and receiving a second sound signal; measuring the propagation time of the sound signals; calculating a value based on the propagation times representative of the concentration; sending and receiving a third sound signal with a second sound conversion unit; measuring a third propagation time; and calculating a second characteristic value based on the first propagation time and the third propagation time, representative of a mass flow of the fluid mixture.

Abstract: An ultrasonic flowmeter for measuring the flow speed and/or the volumetric flow rate of a fluid includes a measurement sensor, at least two ultrasonic transducers, a pressure sensor, and a calibration connector. The ultrasonic flowmeter allows a simple and inexpensive calibration of the pressure sensor in the flowmeter.

Abstract: A flow conduit insert for inserting in a flow conduit of an ultrasonic flow meter. The flow conduit insert being designed for increasing the flow velocity of a fluid flowing through the flow conduit. The flow conduit insert includes a flow controlling arrangement, and a fixation arrangement. The flow controlling arrangement has an inner flow channel with a free passage along the longitudinal center axis of the flow conduit over the entire length of the flow conduit insert. The fixation arrangement is arranged to fixate at least one ultrasound reflector.

Abstract: An ultrasonic flow sensor assembly includes an ultrasonic flow tube, a first reflector, a second reflector, a first ultrasonic transducer, a second ultrasonic transducer, a temperature sensor, and a tube section for accommodating the ultrasonic flow tube. The ultrasonic flow tube includes a water inlet for fixing the first reflector, a water outlet for fixing the temperature sensor and the for fixing the second reflector, a sound channel, a first mounting hole for fixing the first ultrasonic transducer, and a second mounting hole for fixing the second ultrasonic transducer. An entrance of the sound channel is equipped with a chamfer which can make the flow more smoothly and restrain turbulent flow. An installation groove for installing a seal ring is defined at an external sidewall of the ultrasonic flow tube. The ultrasonic flow tube is made of plastic or ceramic.

Abstract: An ultrasonic measurement system and a measurement method thereof are disclosed.

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: Methods and apparatus for measuring liquid fuel flows within a conduit are disclosed. An example flow sensor may include a conduit arranged to flow fuel therethrough along a flow axis, the conduit defining a flow area orthogonal to the flow axis. The flow sensor may further include a first transducer arranged to direct a first signal through the conduit proximate the flow area to a second transducer, the second transducer being arranged to direct a second signal through the conduit proximate the flow area to the first transducer, the first transducer being spaced apart from the second transducer by a signal path length, and in a direction parallel to the flow axis by an axial distance. The fuel flow measuring system may further include a processor arranged to calculate a fuel mass flow rate based on first and second signal transit times, known fuel properties and a fuel temperature.

Abstract: A semiconductor device according to the present embodiment is provided with a controller, a first detector, a second detector, and a determiner. In a first measurement, the first detector detects a first measured value correlated with the propagation time of the first acoustic wave in a first detection period from the transmission to the reception of the first acoustic wave. In a second measurement, the second detector detects a second measured value correlated with the propagation time of the second acoustic wave in a second detection period from the transmission to the reception of the second acoustic wave. The determiner determines the presence or absence of the second measurement on the basis of the result of comparison between the first measured value and another first measured value measured earlier than the first measured value.

Abstract: In a flow meter device of the present invention, a unit measuring step is defined as a procedure for measuring ultrasonic sound wave propagation times by changing the direction in which an ultrasonic sound wave is transmitted and received between a first transducer and a second transducer, and a time measuring means measures a propagation time in a forward direction and a propagation time in a reverse direction in a unit measuring step. A time difference detecting means detects a difference between the propagation time in the forward direction and the propagation time in the reverse direction which are measured by the time measuring means. A determiner means determines whether or not there is a fluid flow based on the time difference. According to presence/absence of a fluid flow, the number of times the unit measuring step is performed is determined. Therefore, it can be determined whether or not there is a fluid flow quickly in real time.

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.

Abstract: Provided is an ultrasonic flow switch which can be stably mounted on pipes. A casing part which integrally or independently holds the ultrasonic wave elements is mounted on an outer surface of the pipe by a clamp part. An acoustic couplant which is formed of a soft elastic body is pressed to an outer surface of the pipe such that at least one of the first and second ultrasonic wave elements is acoustically coupled to the pipe. A collapsing amount of the acoustic couplant at a portion where the collapsing amount of the acoustic couplant caused by the pipe is the largest is restricted by a collapsing amount restricting part.

Abstract: An ultrasound flow meter unit, e.g., a unit forming part of a flow meter for ultrasonic measurement of a fluid flow. The unit comprises two ultrasound transducers 206, a circuit board 202 with an electronic circuit 204 arranged for operating the ultrasound transducers 206, and a common protection membrane 132, such as a sheet of metal, for protecting the transducers 206. The common protection membrane 132 forms part of a water-tight casing, such as an IP68 class casing. The two ultrasound transducers 206 and the circuit board 202 with the electronic circuit 204 are positioned within the water-tight casing and thus protected against damaging humidity. A glass sealed feed-through 128 can be used to provide external electrical contact to the electronic circuit 204, i.e. for outputting an electric flow rate signal. Such flow meter unit is highly versatile within many applications since it provides a compact and robust unit. The unit can be used with or integrated in many types of devices, e.g.

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: A multiphase flowmeter includes a first flow quantity measurer configured to transmit and receive a first measurement signal, the first flow quantity measurer being disposed on an outside wall of a vertical pipe line, a second flow quantity measurer configured to transmit and receive a second measurement signal, the second flow quantity measurer being disposed on an outside wall of a horizontal pipe line which is connected to the vertical pipeline, and a flow quantity parameter calculator configured to receive the first measurement signal from the first flow quantity measurer and the second measurement signal from the second flow quantity measurer, the flow quantity parameter calculating a flow quantity parameter in accordance with the first measurement signal and the second measurement signal.

Abstract: An ultrasound system and a method of detecting vector information with transmission delays are disclosed. In one embodiment, the ultrasound system includes: an ultrasound data acquisition unit configured to set at least two focal points and form ultrasound data corresponding to the respect two focal points by considering transmission delays to the respective focal points; and a processor configured to form vector information of a target object by using the ultrasound data.

Abstract: There is provided a method of measuring the physical properties of a two-phase fluid using at least one piezoelectric oscillator immersed in the two-phase fluid, the two-phase fluid comprising a gas fraction and a liquid fraction, the method comprising: a) measuring the resonant frequency of the or each piezoelectric oscillator as a function of time; and b) determining, from the or each resonant frequency, at least one physical property of the two-phase fluid to characterize the two-phase fluid.

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: A method for monitoring wall thickness of an industrial piping component or pump/fluid machinery, including a pump casing for a pump used for pumping an abrasive fluid or slurry, comprising providing a signal containing information about a ultrasonic-based transducer pulse from a discrete ultrasonic-based transducer attached directly on an industrial piping component or pump/fluid machinery at a local point of interest and configured to inject the ultrasonic-based transducer pulse into the industrial piping component or pump/fluid machinery at the local point of interest and sense the ultrasonic-based transducer pulse reflected off a wall of the industrial piping component or pump/fluid machinery at the local point of interest; and determining with an electronic monitoring system the thickness of the wall of the industrial piping component or pump/fluid machinery at the local point of interest based at least partly on the signal received containing information about the discrete ultrasonic-based transducer pu

Abstract: A method and apparatus for measuring a pulsatingly fluctuating flow rate under a general condition, without needing electrical conductivity for a fluid, and without allowing a phase lag corresponding to a calculation time or attenuation, or resulting from a relation between pressure difference and flow rate, to occur. Ultrasonic waves are repeatedly transmitted with respect to a pulsatingly fluctuating fluid, while the ultrasonic wave is being received, and a signal indicative of the transmission and receipt, and a signal indicative of a timing of the transmission and receipt are recorded. Alternatively, the ultrasonic wave is transmitted and received based on a preliminarily set timing signal, and the signal indicative of the transmission and receipt is recorded. These signals are used to determine flow rates and transmission and receipt timings to plot a pulsating fluctuation. In one or more implementations, the timing signal may be phase-synchronized with a pulsation reference signal.

Abstract: A system and method for ultrasonic flow metering. In one embodiment, an ultrasonic flow metering system includes a passage for fluid flow and a plurality of ultrasonic flowmeters. Each of the ultrasonic flowmeters includes a pair of ultrasonic transducers, and a flow processor. The pair of ultrasonic transducers is configured to form a chordal path across the passage between the transducers. The flow processor is coupled to the ultrasonic transducers. The flow processor is configured to measure the fluid flow through the spool piece based on outputs of the transducers of all of the ultrasonic flowmeters.

Abstract: A self-checking ultrasonic flow meter for measuring fluid flow in a conduit which includes a plurality of transducers engaged with the conduit. The flow meter includes a signal processor in electrical communication with the transducers which produces a measurement of flow rate and an associated estimate of uncertainty due to changes that have affected the accuracy of the measured flow rate. The transducers form multiple transducer pairs positioned to form acoustic transmission paths that are co-located in two or more chordal measurement planes. A plurality of axial velocity measurements are made in each chordal plane. A method for measuring fluid flow in a conduit with an ultrasonic flow meter.

Abstract: A method for generating a Doppler image by using a ultrasound system, the method including: transmitting a ultrasound signal to an object and receiving a response signal reflected from the object; converting the response signal into a plurality of in-phase/quadrature-phase (I/Q) signals having different frequencies; and generating a Doppler image of the object based on information about a speed of the object obtained from the plurality of I/Q signals.

Abstract: An ultrasonic measurement apparatus (10) for determining a fluid velocity of a fluid (12) flowing in a piping (14) is provided, the apparatus (10) having a measurement body (20) inserted into the piping (14) and thus forming a section of the piping (14), the measurement body (20) comprising a flow channel (26) for the fluid (12) and a surrounding channel wall (24), wherein at least one ultrasonic transducer (18a-b) is mounted from the outside on the channel wall (24) so that an oscillating member of the transducer (18a-b) couples onto a partial region (30a-b) of the channel wall (24) and thus the partial region (30a-b) acts as an oscillating membrane of the ultrasonic transducer (18a-b). The ultrasonic transducer (18a-b) is arranged within a bulge (44) of the channel wall (24) which protrudes into the flow channel (26).

Abstract: A gas meter for ultrasound measurements in a breathing apparatus has a gas conduit having an inner wall defining an inlet of the gas conduit and an outlet in a second end of the gas conduit, and an ultrasound transducer arrangement configured to measure the speed of sound in a gas flowing through a part of said gas conduit forming a measurement chamber. The gas meter has a self-draining design to prevent condensation water and other liquids from negatively affecting the ultrasound measurements. To this end, at least a lower surface of the inner wall of the gas conduit is inclined downwardly relative to the horizontal plane in the longitudinal direction of the gas conduit, at both sides of the measurement chamber causing condensation water to be pulled away from the measurement chamber by gravity.

Abstract: A flow-rate measurement device includes a first transducer and a second transducer which are provided in a fluid flow path to transmit and receive an ultrasonic signal, a timer unit which measures a propagation time of the ultrasonic signal propagating between the first transducer and the second transducer, and a flow-rate calculation unit which executes a unit measurement step a predetermined number of times and calculates a flow rate of a fluid flowing in the fluid flow path on the basis of the propagation times measured the predetermined number of times, the unit measurement step being an operation in which a direction of transmission to reception between the first transducer and the second transducer is switched and the timer unit measures the propagation times of the ultrasonic signal in both directions.

Abstract: An ultrasonic sensor assembly for testing a pipe includes a first and second transducer rings attached to the pipe and spaced apart along a length of the pipe. The first transducer ring includes a plurality of transmitters for transmitting a wave, such as a non-dispersive guided wave. The first transducer ring transmits the wave along the pipe. The second transducer ring includes a plurality of receivers for receiving the wave. A relative position of the first transducer ring with respect to a circumferential position of the second transducer ring is determined based on characteristics of the wave received by the second transducer ring. A method of positioning the ultrasonic sensor assembly on the pipe is also provided.

Abstract: An ultrasonic, flow measuring device, comprising an ultrasonic transducer in a bore of a measuring tube, which ultrasonic transducer has an ultrasound window, wherein a guide vane is inserted into the bore of the measuring tube in front of the ultrasound window and perpendicular to the ultrasound window of the ultrasonic transducer.

Abstract: The present invention provides a cartridge for analyzing a fluid sample. The cartridge provides for the efficient separation of cells or viruses in the sample from the remaining sample fluid, lysis of the cells or viruses to release the analyte (e.g., nucleic acid) therefrom, and optionally chemical reaction and/or detection of the analyte. The cartridge is useful in a variety of diagnostic, life science research, environmental, or forensic applications for determining the presence or absence of one or more analytes in a sample.

Abstract: An apparatus and method for determining temperature is disclosed. An ultrasonic signal is generated that propagates through a buffer and a portion of the signal is reflected at an interface. A time of flight is measured between generating the ultrasonic signal and detecting the reflected portion. The temperature is determined based on the time of flight of the reflected signal.

Abstract: There are provided embodiments for changing initial values of a mid-point algorithm to calculate a constant delay value throughout depths based on a sample volume and performing a receive-focusing based on the constant delay value. In one embodiment, an ultrasound system comprises: an ultrasound data acquisition unit configured to calculate a constant delay value throughout depths based on a sample volume by using a mid-point algorithm, transmit ultrasound signals to a living body, receive ultrasound echo signals from the living body and form digital signals based on the ultrasound echo signals, the ultrasound data acquisition unit being further configured to apply the constant delay value to the digital signals to acquire ultrasound data corresponding to a high pulse rate frequency Doppler image of the sample volume.

Abstract: The invention relates to a method for calibrating the transmitters of ultrasonic flow meters according to the transit time difference method. The object of the invention is to provide a method for calibrating the transmitters of ultrasonic flow meters, said calibration being able to be carried out independently of the other components of the meter, such as the acoustic transducers and the pipe in which the fluid flow being measured occurs. According to the invention, the measurement signals are generated by means of an artificial simulation of the measurement path. This allows the transmitter to be calibrated independently of the remaining components of the measuring apparatus, such as the measuring tube and the acoustic transducers.

Abstract: An ultrasonic wave transmitting and receiving unit includes: a piezoelectric member supporting plate; an acoustic matching member fixed to one surface of the piezoelectric member supporting plate; a piezoelectric member fixed to the other surface. Moreover, the ultrasonic wave transmitting and receiving unit includes: an insulating vibration suppressing member integrally formed in such a manner as to cover the piezoelectric member and the piezoelectric member supporting plate, wherein the insulating vibration suppressing member has a hole reaching the piezoelectric member supporting plate.

Abstract: A method and apparatus for predicting the arrival time of a transit vehicle at a transit stop of a transit route is presented. The arrival time is predicted using historical location information of a plurality of vehicles that have previously traveled the route, location information of several of the most recent vehicles that have arrived at the stop, and current location information of a particular vehicle currently traveling the route. Values such as average arrival times and arrival time errors or variances are determined from the historical and recent location data. These values are used with the current location information to predict the arrival time of the particular vehicle.

Abstract: A method for monitoring the operating state of a first ultrasonic transducer in an ultrasonic, flow measuring device having at least one measuring tube and at least two ultrasonic transducers, including steps as follows: a) providing a first value or a plurality of first values, which relate to the geometric arrangement of the first ultrasonic transducer in the measuring tube and/or to the geometric arrangement of the first ultrasonic transducer relative to a second ultrasonic transducer; b) ascertaining a second value or a plurality of second values for a flow velocity of a medium located in the measuring tube c) providing a third value and/or a plurality of third values for temperature and/or pressure of the medium located in the measuring tube; d) simulating a desired value of a signal strength taking into consideration the first, second and/or third values; and e) comparing the simulated desired value of a signal strength with an ascertained real value of the signal strength.

Abstract: A flow rate measuring device simplifies calculation, reduces memory required for calculation, absorbs variations due to manual operation and, depending on the state of ignition, improves the accuracy of appliance identification by extracting features of appliances. The flow rate measuring device includes: a difference value conversion unit that converts into codes difference values of the flow rate measured at constant time intervals by an ultrasonic flowmeter; an appliance feature extraction unit creates an appliance feature code string indicating a feature of each appliance by, for example, making comparison and judgment using a third last code, a second last code, a last code and a current code of the codes obtained at constant time intervals, and by performing code deletion; and an identification unit performs appliance identification by comparing the appliance feature code string with an appliance inherent feature code string indicating the feature code string inherent in each appliance.

Abstract: A system, including an ultrasonic flow meter with a conduit including a conduit wall and configured to flow a fluid, an housing disposed about the conduit to define a fluid chamber about the conduit, wherein the conduit facilitates fluid flow into the fluid chamber and through the ultrasonic flow meter and a first ultrasonic transducer disposed in the fluid chamber.

Abstract: There are disclosed methods and apparatus for monitoring fluid flow along a conduit such as a well bore or a pipeline. A sensor optical fiber is disposed along the conduit, and an optical interrogator is used to launch probe light pulses into the fiber and to determine optical properties of probe light backscattered within the fiber, the properties being indicative of vibration as a function along the fiber. An analyzer is used to detect one or more vibration features moving along the conduit and to determine a measure of fluid flow based on the detected movement.

Abstract: Methods and apparatus for determining the speed of a signal species, such as an acoustic signal, in a multilayered medium is described. The multilayer medium, generally, has a first and second layer (e.g. oil and water), whereby first and second signals are transmitted across particular distances in the medium such that a second distance differs from a first distance, and whereby the time of flight of each signal can be used in order to determine the speed of the signals species in one or both of the first and second layer. In other words, in some cases, the speed of sound can be determined in oil and/or water, or the like.

Abstract: Ultrasonic flow rate measurement device includes measurement flow path in which a fluid to be measured flows, and a pair of ultrasonic vibrators that are disposed in directions such that a propagation path of an ultrasonic wave forms a V-shape relative to measurement flow path. Moreover, the device includes measurement circuit which measures a flow rate of the fluid to be measured by measuring a propagation time of the ultrasonic wave between the pair of ultrasonic vibrators, and inlet-side rectification part which is disposed, in the inlet side of measurement flow path, to stabilize the flow of the fluid to be measured. Furthermore, the device includes outlet-side coupling part which is disposed in the outlet side of measurement flow path, and signal lead-out part which outputs a flow rate value measured with measurement circuit.

Abstract: Pairs of acoustic transducers positioned at different radial distances in a conduit are used to measure travel times of acoustic signals in opposite directions and inclined to the direction of a fluid flow in the borehole. These contrapropagation measurements are used to estimate fluid velocity and volumetric flow rates of the fluid components in the conduit.

Abstract: In a flow meter device of the present invention, a time measuring section of the flow meter device includes a first counter which starts counting at a starting point of measurement of propagation time; and a second counter which starts counting at an end point of the measurement of the propagation time, and performs counting at a higher speed than the first counter. A propagation time TO is finally obtained by subtracting time ?t which is measured by the second counter and passes from the end point until the first counter counts up, from time T which is measured by the first counter and passes from a starting point until the first counter counts up after the end point. A flow calculating section calculates a flow with high accuracy using the propagation time TO. Thus, lower electric power consumption can be achieved, and accuracy of measurement of flow can be improved.