The present disclosure provides an aerosol sensing method. The aerosol sensing method includes steps of providing an entering process, providing a particle collecting process and providing a measuring process. The entering process is to allow an aerosol to enter a chamber of a thermal-piezoresistive oscillator-based aerosol sensor, and a thermal-piezoresistive resonator is disposed in the chamber. The particle collecting process is to allow particulate matters in the aerosol to land on at least one proof-mass of the thermal-piezoresistive resonator when the thermal-piezoresistive resonator is not driven. The measuring process is to use an electrical signal to drive the thermal-piezoresistive resonator and measure a resonant frequency of the thermal-piezoresistive resonator. The particle collecting process and the measuring process are operated in a repetitive cycle for measuring changes of the resonant frequency of the thermal-piezoresistive resonator to measure the particulate matters of the aerosol.

A multi-probe system for real-time measurement of a fluid level in a pipe with steady-state and turbulent flow conditions is presented. The multi-probe system includes a plurality of multiplexed transducers attached in a non-destructive fashion to walls of the pipe. Multiplexing of the transducers activate and deactivate the transducers in sequence to generate independent pairs of transmit and receive wave signals through the pipe. Each transmit and receive signal pair can be used to independently establish a time-of-flight from the transducer and back to the transducer as reflected by a surface of the fluid. The transducers can be arranged as longitudinal and/or circumferential arrays on the walls of the pipe. An algorithm that determines the time-of-flight eliminates received signals having an energy level lower than or equal to a predefined minimum energy level and eliminates any time-of-flight that is shorter than a minimum threshold time.

The present disclosure provides an aerosol sensing method. The aerosol sensing method includes steps of providing an entering process, providing a particle collecting process and providing a measuring process. The entering process is to allow an aerosol to enter a chamber of a thermal-piezoresistive oscillator-based aerosol sensor, and a thermal-piezoresistive resonator is disposed in the chamber. The particle collecting process is to allow particulate matters in the aerosol to land on at least one proof-mass of the thermal-piezoresistive resonator when the thermal-piezoresistive resonator is not driven. The measuring process is to use an electrical signal to drive the thermal-piezoresistive resonator and measure a resonant frequency of the thermal-piezoresistive resonator. The particle collecting process and the measuring process are operated in a repetitive cycle for measuring changes of the resonant frequency of the thermal-piezoresistive resonator to measure the particulate matters of the aerosol.

An example system includes at least one acoustic sensor configured to generate at least one acoustic data signal indicative of an acoustic signal generated by a thermal spray system comprising a flowstream, a computing device, and an acoustic data signal processing module operable by the computing device to determine an ignition attribute of the thermal spray system by analyzing at least a pre-ignition window of the acoustic data signal received by the computing device.

A fluid sensing system including a first transducer, a second transducer, a filter, and a controller. The first transducer is configured to output a first sound wave through a first fluid in a first measurement channel. The second transducer is configured to output a second sound wave through a second fluid in a second measurement channel. The filter is configured to substantially prevent aeration in the second fluid contained within the second measurement channel. The controller is configured to determine a first characteristic of the first sound wave, and determine a second characteristic of the second sound wave. The controller is further configured to determine a percentage of aeration by volume within the first fluid based on the first characteristic and second characteristic, and output the percentage of aeration by volume within the first fluid.

A multi-probe system for real-time measurement of a fluid level in a pipe with steady-state and turbulent flow conditions is presented. The multi-probe system includes a plurality of multiplexed transducers attached in a non-destructive fashion to walls of the pipe. Multiplexing of the transducers activate and deactivate the transducers in sequence to generate independent pairs of transmit and receive wave signals through the pipe. Each transmit and receive signal pair can be used to independently establish a time-of-flight from the transducer and back to the transducer as reflected by a surface of the fluid. The transducers can be arranged as longitudinal and/or circumferential arrays on the walls of the pipe. An algorithm that determines the time-of-flight eliminates received signals having an energy level lower than or equal to a predefined minimum energy level and eliminates any time-of-flight that is shorter than a minimum threshold time.

The present technology is directed to the integration of a fixed ultrasonic device into a connector fitting adapted to connect fluid conduits, as well as methods of detecting the presence or absence of media passing through a fitting.

In one embodiment, a photoacoustic effect measurement instrument for measuring a species (e.g., a species of PM) in a gas employs a pair of differential acoustic cells including a sample cell that receives sample gas including the species, and a reference cell that receives a filtered version of the sample gas from which the species has been substantially removed. An excitation light source provides an amplitude modulated beam to each of the acoustic cells. An array of multiple microphones is mounted to each of the differential acoustic cells, and measures an acoustic wave generated in the respective acoustic cell by absorption of light by sample gas therein to produce a respective signal. The microphones are isolated from sample gas internal to the acoustic cell by a film. A preamplifier determines a differential signal and a controller calculates concentration of the species based on the differential signal.

Provided is a fluid state identification device including a fluid state identification unit having a sensor part and a support part, and a cover surrounding the fluid state identification unit. The support part has a front surface part and a rear surface part which are located opposite to each other. The sensor part is located on the front surface part side. The cover has a lower opening and an upper opening. Inside the cover, a first fluid flow route running through a front area adjacent to the support front surface part and a second fluid flow route running through a rear area adjacent to the support rear surface part are formed and located so as to make the fluidity of the fluid in the second fluid flow route higher than the fluidity of the fluid in the first fluid flow route.

A method of determining the phase compositions of a multiphase fluid flow in a fluid line, including obtaining a vibration signal from the fluid flow using a vibration sensor comprising a target disposed in the fluid flow which vibrates in response to fluid flow in the fluid line. The vibration signal is analyzed to determine a first energy parameter which is related to the energy of the vibration signal within a first frequency band, and a second energy parameter which is related to the energy of the vibration signal within a second frequency band; and a phase composition parameter, such as a dryness parameter, relating to the phase compositions of the fluid flow is determined using the first and second energy parameters. An apparatus for determining the phase compositions of a multiphase fluid flow in a fluid line.