The present disclosure relates to a method for measuring the flow of a liquid medium having variable gas content, on the basis of a differential pressure measurement by means of a differential pressure-generating primary element, through which the medium flows, which method comprises: ascertaining a differential pressure measurement value between two measuring points of the differential pressure-generating primary element; ascertaining a flow regime; ascertaining a flow rate measurement value as a function of the differential pressure measurement value and the flow regime, wherein the flow rate measurement value is ascertained by ascertaining a provisional flow rate measurement value on the basis of the differential pressure measurement value under the assumption of a first flow regime, which provisional flow rate measurement value is corrected if a second flow regime different from the first flow regime is detected.

Methods and apparatus, such as a controller of a respiratory therapy device, generate a signal representing an estimate of flow rate of gas flow from the device. The respiratory therapy device may include a motor-operated blower. The method may include receiving in the controller, signals generated by a set of sensors, including measures of pressure and frequency (e.g., speed) of the motor. The controller may be configured to compute an entrained air density function and generate the estimate signal based on a function of the measures of pressure and frequency, and the entrained air density function. The entrained air density function may apply signals from additional sensors, such as atmospheric pressure, gas temperature, and ambient relative humidity, to compute atmospheric density. Control operations of the therapy device may then be based on the estimated signal, which may be applied to assess accuracy of a signal from a flow sensor.

A novel thermopile having high sensitivity and reliability at the time of measuring a flow rate of gas in a thermopile sensor is provided. A thermopile sensor includes a thermopile in which pairings of PolySi and a metal film are connected in series on an insulating film, the metal film is connected so as to overlap on the PolySi in each pair, the metal film crosses a gap between the PolySi and the PolySi in a connection portion between pairings, and a gap between the PolySis in a portion where the metal film crosses is wider than a gap between the PolySis in the remaining portion.

An aspect of the present invention pertains to a method for determining the volumetric flow rate of a compressible fluid flow flowing through a volume flowmeter having a flow inlet, a wheel downstream of the flow inlet and a constriction downstream of the flow inlet and upstream of the wheel, the compressible fluid flowing through the flow inlet and actuating the wheel. The method comprises measuring the rotational speed of the wheel and determining the permanent pressure loss across the wheel based on the measured rotational speed. The method further comprises measuring the fluid pressure of the compressible fluid flow at the flow inlet and determining whether the compressible fluid flow in the volume flowmeter is in the subsonic or in the supersonic regime based on the determined permanent pressure loss and the measured fluid pressure. The method also comprises measuring the fluid temperature of the compressible fluid flow at the flow inlet and determining the volumetric flow rate of the compressible fluid flow based on the determined permanent pressure loss, the measured fluid pressure, the regime of the compressible fluid flow and the measured fluid temperature. Other aspects of the present invention pertain to volume flowmeter for determining the volumetric flow rate of a compressible fluid flow, a data processing device for controlling a volume flowmeter, a computer program for the controller and a computer-readable medium having stored thereon the computer program.

A measurement control device includes: a sensing unit that outputs a signal according to an air flow rate; a pulsation state calculation unit that calculates a pulsation state of pulsation generated in the air flow rate using an output value of the sensing unit; and a pulsation error correction unit that corrects the air flow rate. The pulsation state calculation unit has an upper extreme value determination unit and a frequency calculation unit. The upper extreme value determination unit cancels the upper extreme value that has presently appeared, when the output value remains to be more than a predetermined lower threshold. The upper extreme value determination unit updates the lower threshold on a basis of at least one of air flow rate, pulsation frequency, or pulsation amplitude specified on the basis of the output value.

A quantity of gas is introduced into a gas reservoir via a filling station provided with a filling line. The quantity is measured. A signal is generated indicating a corrected quantity of transferred gas. The signal is obtained by adding a predetermined, positive or negative, corrective amount to the measured quantity of gas transferred.

An electronic utility gas meter using MEMS thermal time-of-flight flow sensor to meter gas custody transfer mass flowrate and an additional MEMS gas sensor to measure the combustion gas composition for the correlations to the acquisition of gas high heat value simultaneously is disclosed in the present invention. The meter is designed for the applications in the city utility gas consumption in compliance with the current tariff while metering the true thermal value of the delivered gases for future upgrades. Data safety, remote data communication, and other features with state-of-the-art electronics are also included in the design.

In order to provide a fluid device that makes it possible for operation command signals other than existing operation command signals to be received without a software modification having to be implemented in an already constructed system, in a fluid device that measures or controls physical quantities of a fluid, there are provided a command signal receiving unit that receives a predetermined plurality of types of operation command signals, and also command signal modes, which are values thereof or time series variations of the values thereof, and a command signal recognition unit that, when the command signal mode of a predetermined operation command signal received by the command signal receiving unit falls outside predetermined conditions that have been set in advance, recognizes the predetermined operation command signal that contains the command signal mode as being a different type of operation command signal.

A flow measurement device includes a flow rate measurement unit, an arithmetic unit that calculates a difference value between a the first flow rate value and a second flow rate value, and a difference value conversion unit that calculates a flow rate ratio, based on the difference value. An appliance characteristic extraction unit extracts at least one appliance characteristic quantity indicating a characteristic of a flow rate change and a value calculated from a first flow rate value and a second flow rate value, as an appliance characteristic quantity. Furthermore, an appliance inherent characteristic information holding unit holds appliance inherent characteristic quantities indicating a characteristic flow rate state of a specific gas appliance, and an appliance discrimination unit discriminates a gas appliance, based on a comparison between the appliance characteristic quantity and the appliance inherent characteristic quantity.

In a measurement control device that measures an airflow, an amplitude calculator calculates, by use of an output value of a sensor, a pulsation amplitude that is a difference between a pulsation maximum and an average airflow or a difference between the pulsation maximum and a pulsation minimum. The pulsation maximum is a maximum value of pulsation generated in the airflow, the average airflow is an average value of the pulsation, and the pulsation minimum is a minimum value of the pulsation. A correction parameter acquirer acquires a correction parameter corresponding to the calculated pulsation amplitude by use of a correction characteristic. An airflow corrector corrects the airflow by use of the acquired correction parameter.