A throughflow measurement system for measuring a fluid throughflow through a pipe comprises a first measurement arrangement that comprises at least two ultrasonic transducers and that is configured to determine a value for the fluid throughflow through the pipe on the basis of transit times of ultrasonic signals transmitted and received with and against the flow; a second measurement arrangement that comprises a plurality of hot-wire sensors that are arranged distributed over the cross-section of the pipe and that are each configured to determine a local flow value; and an evaluation device that is in signal connection with the first measurement arrangement and with the second measurement arrangement and that is configured to determine a flow profile on the basis of the local flow values determined by the hot-wire sensors and to modify the value for the fluid throughflow, which is determined by the first measurement arrangement, on the basis of the determined flow profile.

A throughflow measurement system for measuring a fluid throughflow through a pipe comprises a first measurement arrangement that comprises at least two ultrasonic transducers and that is configured to determine a value for the fluid throughflow through the pipe on the basis of transit times of ultrasonic signals transmitted and received with and against the flow; a second measurement arrangement that comprises a plurality of hot-wire sensors that are arranged distributed over the cross-section of the pipe and that are each configured to determine a local flow value; and an evaluation device that is in signal connection with the first measurement arrangement and with the second measurement arrangement and that is configured to determine a flow profile on the basis of the local flow values determined by the hot-wire sensors and to modify the value for the fluid throughflow, which is determined by the first measurement arrangement, on the basis of the determined flow profile.

A portable fuel metering system (PMU) is described. The PMU has one or more flow meters capable of metering the flow of fluids, such as fuel, as the fluid is transferred from a source to a receiver. The PMU may include a telemetry unit configured to transmit parameters related to the fuel transfer to remote location. The PMU may be configured in a light, portable package that may be carried by one or two people. The PMU may include a power generator that is configured to use the flow of fluid to the PMU to generate power for the PMU's operation.

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.

An ultrasonic gas flow meter based on FPGA and DSP consists of ultrasonic gas transducers and sensor components, transmitting/receiving signal channel switch circuits, a driving signal generation and amplification circuit, an echo signal conditioning and collection circuit, a time sequential controlling and signal processing circuit, a man-machine interface, a serial communication module and a power management module, propagation time of ultrasonic echo waves is calculated by adopting a variable ratio threshold and zero-crossing detection method of tracking maximum peak of the echo signal to obtain gas flow rates.

An ultrasound measuring apparatus for measuring the flow rate of a fluid in a conduit having two measurement systems is provided that each have at least one pair of ultrasound transducers that span a measurement path between them and that each have a control unit to determine transit times from ultrasound transmitted and received with and against the flow. In this respect, the control units are each configured to fix measurement times for a transit time determination on a measurement path autonomously and independently of one another in accordance with a rule that produces a respective different sequence of the measurement times in both measurement systems.

A Holographic Multiphase Flowmeter permits reconstructing the type, size and distribution of Objects within a Multiphase Medium by analysis of the ultrasonic energy reflected from these Objects. If this Multiphase Medium is flowing through a pipe into which a preferred mode of ultrasonic energy is injected at a Reference location, and the amplitude of reflections from the current multiphase Objects at that location and the time it took after the last transmission for that reflected signal amplitude to arrive at the Receive transducer are recorded, it is possible to determine the velocity of the medium by measuring the travel time taken for these same Objects to arrive at a known distance downstream by correlating the same type of reflection data at this second Correlation location. Analysis of this data permits displaying type and size of the Objects in a graphic image showing their distribution within the liquid in real time.

A flow-rate measuring apparatus transmits and receives a measurement signal between first and second transducers through a fluid inside a pipe, the measurement signal having a plurality of frequencies and a time length. The flow-rate measuring apparatus calculates a correlation coefficient between a reference signal corresponding to the transmitted measurement signal, and the received measurement signal. The flow-rate measuring apparatus calculates a flow rate of the fluid inside the pipe based on the measurement signal, when a peak value of the correlation coefficient is higher than a threshold. The flow-rate measuring apparatus retransmits the measurement signal with changing at least one of the frequency and the time length of the measurement signal, when the peak value of the correlation coefficient is equal to or lower than the threshold.

A method of operating an acoustic resonance fluid flow sensor. The method comprises emitting an acoustic stimulus signal comprising a plurality of frequencies into an acoustic resonance cavity of the acoustic resonance fluid flow sensor, sensing an acoustic response signal within the acoustic resonance cavity and deriving the phases or equivalent group delays of one or more frequency components of a frequency spectrum of the acoustic response signal.

Passive wireless sensors include an antenna. The antenna receives a combined signal. The combined signal includes a low frequency modulating signal modulated on a high frequency carrier wave. A demodulator receives the combined signal and extracts the modulating signal. A sensor receives the extracted modulating signal and produces an output signal with a time delay indicative of a property to be sensed. A modulator receives the output signal and the high frequency carrier wave and modulates the output signal onto the high frequency carrier wave to create a combined output signal broadcast by the antenna.