An article having: an elastomeric jacket; a gel within the jacket; and a plurality of gas-filled, polymerically-encapsulated microbubbles suspended in the gel. The microbubbles have a Gaussian particle size distribution. The largest microbubble has a diameter at least 10 times the diameter of the smallest microbubble. The article may exhibit Anderson localization at at least one frequency of sound waves impacting the article.

A fluid analysis system for characterizing a multiphase fluid includes a first set of acoustic probes disposed at a first angular position about a central axis of the fluid analysis system and oriented to direct first sound waves along a first direction that is parallel to the central axis, a second set of acoustic probes disposed at a second angular position about the central axis that is opposite to the first angular position and oriented to direct second sound waves along the first direction, a third set of acoustic probes spanning the central axis and oriented to direct third sound waves along a second direction that is perpendicular to the central axis, and an analysis unit. The analysis unit is configured to determine a location of a fluid interface within the multiphase fluid based on first, second, and third parameters respectively associated with the first, second, and third sounds waves.

Apparatus is provided having an acoustic-based air probe with an acoustic source configured to provide an acoustic signal into a mixture of concrete; and an acoustic receiver configured to be substantially co-planar with the acoustic source, to respond to the acoustic signal, and to provide signaling containing information about the acoustic signal injected into the mixture of concrete.

A circuit for detecting air, a related system, and a related method are provided. The circuit for detecting air includes a receiver connection and an air-detection circuit. The receiver connection is configured to provide a receiver signal. The air-detection circuit is in operative communication with the receiver connection to process the receiver signal to generate a processed signal corresponding to detected air. The air-detection circuit includes one or more active-rectifying elements configured to actively rectify the receiver signal to provide the processed signal.

A method of measuring the speed of a fluid includes: a measurement stage comprising the steps of emitting a measurement ultrasonic signal, of acquiring a main ultrasonic signal resulting from the measurement ultrasonic signal, and of analyzing the main ultrasonic signal in order to produce a present measurement of the travel time; a validation stage for validating the present measurement, the validation stage comprising the steps of acquiring a secondary ultrasonic signal also resulting from the measurement ultrasonic signal but delayed because of the presence of gas bubbles in the fluid, of evaluating one or more first parameters in the secondary ultrasonic signal that are representative of the quantity of gas bubbles in the fluid, and of validating or invalidating the present measurement as a function of the first parameter(s).

Provided is an ultrasonic liquid concentration detecting device including a vibrating structure, a bubble removing structure, and an ultrasonic detecting main body. The vibrating structure is disposed at the bottom of the ultrasonic detecting main body and is configured to buffer a shock received by the ultrasonic detecting main body. The bubble removing structure is disposed on the ultrasonic detecting main body and is configured to accelerate the flow rate of a liquid. The ultrasonic detecting main body is configured to detect a concentration of the liquid. Further provided are a bubble removing device and a vibrating structure for an ultrasonic liquid concentration detecting device.

To detect air in a fluid delivery line of an infusion system, infusion fluid is pumped through a fluid delivery line adjacent to at least one sensor. A signal is transmitted and received using the at least one sensor into and from the fluid delivery line. The at least one sensor is operated, using at least one processor, at a modified frequency which is different than a resonant frequency of the at least one sensor to reduce an amplitude of an output of the signal transmitted from the at least one sensor to a level which is lower than a saturation level of the analog-to-digital converter to avoid over-saturating the analog-to-digital converter. The signal received by the at least one sensor is converted from analog to digital using an analog-to-digital converter. The at least one processor determines whether air is in the fluid delivery line based on the converted digital signal.

A method and apparatus for determining a gas influx into a wellbore. A work string defining an inner bore area and an annulus area, with a pair of inner bore sensors in the inner bore and a pair of annulus sensors in the annulus. A processor sets a gas influx alarm limit based on a steady-state value of an acoustic parameter measured by the pair of inner bore sensors in an absence of a gas influx and a steady-state value of the acoustic parameter measured by the annulus sensors in the absence of the gas influx. The processor determines a gas influx in the wellbore when a subsequent value of the acoustic parameter is outside of the alarm limit and performs an action at the work string to counteract the gas influx in the wellbore.

Disclosed is an air in infusion line detecting device, comprising an acoustic emitter adapted to be provided at one side of an infusion line and to vibrate at its resonance frequency so as to transmit an acoustic sound wave with a frequency corresponding to said resonance frequency, and an acoustic receiver adapted to be provided at another side of the infusion line and to be set into vibrations caused by the sound wave transmitted by said emitter through the infusion line and to generate an output signal indicating the characteristics of said vibrations. The device is characterized in that the resonance characteristics of said emitter and/or the distance between said emitter and said receiver is adapted so that the sound wave is generated as a standing wave between said emitter and said receiver.

The invention provides a signal processor that receives a signal containing information about an acoustic signal that is generated by at least one acoustic transmitter, that travels through an aerated fluid in a container, and that is received by at least one acoustic receiver arranged in relation to the container, including inside the container; and determines the gas volume fraction of the aerated fluid based at least partly on the speed of sound measurement of the acoustic signal that travels through the aerated fluid in the container. The signal processor also sends an output signal containing information about the gas volume fraction of the aerated fluid. The signal processor may be configured together with at least one acoustic transmitter, the at least one acoustic receiver, or both.