An environment detection system includes a sound wave transmitter, a sound wave receiver, and a control unit. The sound wave transmitter transmits a detection sound wave to a target space. The sound wave receiver receives the detection sound wave transmitted by the sound wave transmitter. The control unit controls the sound wave transmitter. The environment detection system detects at least either a temperature distribution or an air velocity distribution in the target space. The control unit executes a first control to regulate at least either a volume or a frequency of the detection sound wave transmitted by the sound wave transmitter so that a volume of the detection sound wave received by the sound wave receiver is higher than or equal to a predetermined reference reception volume.

A measuring device for non-mechanical-contact measurement of a layer, the measuring device including a light source operative to generate a pulse adapted to interact with the layer so as to generate a thermal wave in a gas medium present adjacent the layer. The thermal wave causes an acoustic signal to be generated. The measuring device further includes a detector adapted to detect a first signal responsive to the acoustic signal, the detector not being in mechanical contact with the layer. The first signal is representative of the measured layer.

A system and method for measuring rheology of a treatment fluid. The system may comprise an ultrasound transmitter positioned to direct ultrasound pulses into the treatment fluid as the treatment fluid is being introduced into a wellbore; an ultrasound receiver positioned to receive sound waves reflected from the treatment fluid; and a computer system configured to determine a velocity profile of the treatment fluid based at least in part on the reflected sound waves. The method may comprise introducing a treatment fluid into a wellbore by way of a conduit; directing ultrasound pulses into the treatment fluid; measuring sound waves reflected by the treatment fluid; and determining a velocity profile of the treatment fluid based at least on the measured sound waves.

An embodiment provides a method for measuring a fluid parameter of fluid flowing in a channel, including: transmitting, using a transmitter of a device, directed energy carrying a signal toward a surface of a fluid in a fluid channel, so as to produce one or more reflections from the fluid surface; detecting, by at least one receiver of the device, one or more received signals associated with the one or more reflections so produced; and determining, based upon a measurement beam comprising characteristics of the transmitted and received signals, a fluid parameter to be measured using a processor of the device; wherein, a measurement beam characteristic is adjusted based on a distance from the device to the fluid surface. Other embodiments are described and claimed.

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.

Detection of gas characteristics, especially the detection of the gas composition, the temperature and/or humidity of a gas, by measuring the speed of sound with a sound sender and a sound receiver both mounted on common structure. A method for determining the humidity of the scavenge air of an internal combustion engine. A speed of sound based gas sensor arrangement adapted to measure gas characteristics, especially the gas composition, the temperature and/or the humidity of a gas, including a sender, a receiver and a signal processing unit. The speed of sound is determined by driving the sender and receiver at different operation cycles in order to differentiate between the different travel times of the sound through the gas and the common structure of solid material.

Detection of gas characteristics, especially the detection of the gas composition, the temperature and/or humidity of a gas, by measuring the speed of sound with a sound sender and a sound receiver both mounted on common structure. A method for determining the humidity of the scavenge air of an internal combustion engine. A speed of sound based gas sensor arrangement adapted to measure gas characteristics, especially the gas composition, the temperature and/or the humidity of a gas, including a sender, a receiver and a signal processing unit. The speed of sound is determined by driving the sender and receiver at different operation cycles in order to differentiate between the different travel times of the sound through the gas and the common structure of solid material.

A method for the measurement of the speed of sound in a gas suitable for the determination of gas characteristics, especially the composition of the gas, the temperature and/or the humidity of the gas, and a speed of sound based gas sensor arrangement adapted to measure that gas characteristics comprising sound sending means and sound receiving means and signal processing unit. A sound sender is used as sound sender and a first sound receiver and a second sound receiver as sound receiving means, all three of them being arranged such that the travel distance of the sound provided by the sender to the first receiver is different from the travel distance of the sound provided by the sender to the second receiver. Further the arrangement includes the signal processing means connected with the sender and the receivers which operate the sender and determine gas characteristics, especially the composition of the gas, the temperature and/or the humidity of the gas, from the different signals provided by the first and the second receiver.

A method for the measurement of the speed of sound in a gas suitable for the determination of gas characteristics, especially the composition of the gas, the temperature and/or the humidity of the gas, and a speed of sound based gas sensor arrangement adapted to measure that gas characteristics comprising sound sending means and sound receiving means and signal processing unit. A sound sender is used as sound sender and a first sound receiver and a second sound receiver as sound receiving means, all three of them being arranged such that the travel distance of the sound provided by the sender to the first receiver is different from the travel distance of the sound provided by the sender to the second receiver. Further the arrangement includes the signal processing means connected with the sender and the receivers which operate the sender and determine gas characteristics, especially the composition of the gas, the temperature and/or the humidity of the gas, from the different signals provided by the first and the second receiver.

A sonic speed measurement device includes a reception array in which a plurality of reception elements which output reception signals in response to reception of an ultrasonic wave are disposed in one direction, a phase difference detection portion that detects a phase difference between the reception signals output from the reception elements adjacent to each other in a case where the plurality of reception elements receive the ultrasonic wave which propagates in a spherical wave shape from a target point, and a sonic speed calculation portion that calculates a sonic speed of the ultrasonic wave on the basis of the phase difference.