Embodiments of the present disclosure provide an apparatus for determining a characteristic of a fluid. The apparatus may include a device configured to determine a hydrodynamic pressure of the fluid. The apparatus may further include a sensor configured to determine a hydrostatic pressure of the fluid or at least one component of the fluid. The apparatus may also include a common substrate on which the sensor and the device configured to determine a hydrodynamic pressure of the fluid may be commonly arranged, and an ASIC (Application Specific Integrated Circuit) which may be electrically coupled with at least one of the device or the sensor. The ASIC may be at least partially embedded in the common substrate.

A method of measuring a residence time in a gas-turbine engine is disclosed that includes measuring a combustor pressure signal at a combustor entrance and a turbine exit pressure signal at a turbine exit. The method further includes computing a cross-spectrum function between the combustor pressure signal and the turbine exit pressure signal, calculating a slope of the cross-spectrum function, shifting the turbine exit pressure signal an amount corresponding to a time delay between the measurement of the combustor pressure signal and the turbine exit pressure signal, and recalculating the slope of the cross-spectrum function until the slope reaches zero.

A method of measuring a residence time in a gas-turbine engine is disclosed that includes measuring a combustor pressure signal at a combustor entrance and a turbine exit pressure signal at a turbine exit. The method further includes computing a cross-spectrum function between the combustor pressure signal and the turbine exit pressure signal, calculating a slope of the cross-spectrum function, shifting the turbine exit pressure signal an amount corresponding to a time delay between the measurement of the combustor pressure signal and the turbine exit pressure signal, and recalculating the slope of the cross-spectrum function until the slope reaches zero.

An apparatus and method for measuring the internal pressure of a pipe or container is disclosed. The apparatus includes an acoustical transmitter (Tx.sub.1) mounted on a wall (1) of said pipe or container and a signal generator (2) connected to said transmitter and which is adapted to provide a signal to the transmitter. The signal from the transmitter is detected by two receivers (Rx.sub.1, Rx2) mounted on said pipe or container in a distance from said transmitter (Tx.sub.1). A processing unit (3) is connected to said transmitter and receivers, the processing unit being adapted to measure the travel time of an acoustical signal propagating between two receivers in the wall (i) and determine the pressure inside the pipe or container from said travel time.

An apparatus and method for measuring the internal pressure of a pipe or container is disclosed. The apparatus includes an acoustical transmitter (Tx.sub.1) mounted on a wall (1) of said pipe or container and a signal generator (2) connected to said transmitter and which is adapted to provide a signal to the transmitter. The signal from the transmitter is detected by two receivers (Rx.sub.1, Rx2) mounted on said pipe or container in a distance from said transmitter (Tx.sub.1). A processing unit (3) is connected to said transmitter and receivers, the processing unit being adapted to measure the travel time of an acoustical signal propagating between two receivers in the wall (i) and determine the pressure inside the pipe or container from said travel time.

A flow-through pressure transducer comprising a cylindrical diaphragm positionable to allow fluid to flow therethrough which responds to variations in fluid pressure to generate an electrical signal proportional to such variations and which is incorporated in a housing for interconnecting with fluid delivery tubing. The diaphragm is made of relatively thin resilient metal, shaped to be a tube, elliptical in cross-section, with transducers, located on the elliptical major and minor axes which change their electrical state in response to movement of the diaphragm walls, and which are coupled in a bridge circuit for signal measurement. The housing is constructed for either gage or absolute fluid pressure measurements.

A pressure monitoring system for a compressed fluid source may comprise a surface acoustic wave sensor and a controller operably coupled to the surface acoustic wave sensor. The controller may be configured to send a first radio frequency signal to the surface acoustic wave sensor, receive a second radio frequency signal from the surface acoustic wave sensor, and determine a pressure of the compressed fluid source based on the first radio frequency signal and the second radio frequency signal.

A pressure monitoring system for a compressed fluid source may comprise a surface acoustic wave sensor and a controller operably coupled to the surface acoustic wave sensor. The controller may be configured to send a first radio frequency signal to the surface acoustic wave sensor, receive a second radio frequency signal from the surface acoustic wave sensor, and determine a pressure of the compressed fluid source based on the first radio frequency signal and the second radio frequency signal.

A system to determine a temperature corrected pressure of a medium in a pressure transducer is disclosed. The system comprises a first circuitry to obtain a first value related to a vibration frequency of the vibration of a pressure sensitive vibration member; a second circuity to obtain a second value related to a vibration amplitude of the vibration of the vibration member; and a third circuity to use the first value and the second value to determine the temperature corrected pressure of the medium based on a predetermined relationship between the vibration frequency and the vibration amplitude.

A system to determine a temperature corrected pressure of a medium in a pressure transducer is disclosed. The system comprises a first circuitry to obtain a first value related to a vibration frequency of the vibration of a pressure sensitive vibration member; a second circuity to obtain a second value related to a vibration amplitude of the vibration of the vibration member; and a third circuity to use the first value and the second value to determine the temperature corrected pressure of the medium based on a predetermined relationship between the vibration frequency and the vibration amplitude.