A method and apparatus for determining the flow rates of a multi-component fluid mixture is disclosed. The temperature and pressure of the multi-component mixture is determined. The fractions of the multi-component mixture are determined based on at least two measured physical properties of the mixture and knowledge of the same physical property of the individual components. The velocity of the multi component mixture is determined. The flow rate of the individual component of the fluid is determined. An electromagnetic measurement is performed. A statistical parameter related to the electromagnetic measurement is calculated and compared to an empirical derived threshold value corresponding to the value of the statistical parameter when only one of the components of the multi component mixture is present. The thickness of unwanted deposits on the pipe wall is determined and an improved flow rate determination of the individual components of the fluid is obtained.

A method for determining the flow rates of a fluid comprising a multi-component mixture of a gas and at least one liquid in a pipe, the method comprising the following steps: a. The temperature and pressure of the multi-component mixture is determined, b. the fractions of the multi-component mixture is determined based on at least two measured physical properties of the multi-components mixture and knowledge of the same physical property of the individual components of the multi-component mixture, c. the velocity of the multi component mixture is determined, d. based on the result from step a-c, the flow rate of the individual component of the fluid is determined, characterized by a method for determining the physical properties of at least one of the components of the multi-component mixture where e. an electromagnetic loss or phase measurement is performed, f. a statistical parameter related to the electromagnetic measurement is calculated, g. the said statistical parameter is compared to an empirical derived threshold value corresponding to the value of the statistical parameter when only one of the component of the multi component mixture is present, and h. the said physical properties of said fluid is determined if the statistical parameter exceeds the threshold value for the said component and used in step b-d to provide an improved value of the fractions, velocity and flow rate of the individual components of the multi-component mixture. An apparatus for performing the method is also disclosed.

Storage units 60, 70 store a first computer program calculating a flow rate of an assist gas with a linear function having a pressure of the assist gas in a processing head 35 as a variable, and a second computer program calculating a slope of the linear function with a function having a gap G from a tip end of a nozzle 36 to a surface of a workpiece W as a variable. A control unit 50 substitutes a value of the gap G into the function to calculate the slope of the linear function and substitutes the slope of the linear function and a value of the pressure of the assist gas into the linear function to calculate the flow rate of the assist gas.

A multivariable transmitter is provided for measuring multiple process fluid variables. The multivariable transmitter includes a metal housing constructed from a material suitable for exposure to a corrosive material, such as seawater. A differential pressure sensor is disposed within the metal housing. A line pressure sensor is also disposed within the metal housing. Measurement circuitry is operably coupled to the differential pressure sensor and the line pressure sensor to provide differential pressure and line pressure outputs. A temperature probe has a sheath constructed from a material suitable for exposure to the corrosive material. The temperature probe is electrically coupled to circuitry within the metal housing and is physically coupled to the metal housing via a high-pressure coupling.

A flow generator (21) for a respiratory therapy system configured to deliver a breathable gas flow to a patient comprises a housing (27) comprising an inlet (28) and an outlet (25) and a gas flow path between the inlet (28) and outlet (25). An impeller is mounted within the housing (27) for rotation about an axis, the impeller configured to be rotationally driven by a motor to provide a gas flow along the gas flow path. Various embodiments are disclosed in which the flow generator (21) further comprises a sensor (23) mounted in the housing (27) in the gas flow path and configured to detect a property of the gas flow. The sensor (23) may be mounted in the outlet (25) so as to project into the gas flow path. Flow generator may comprise an axial inlet (28) and a tangential outlet (25). In another embodiment the sensor (23) may be mounted in the inlet (28).

The flow rate control device 10 includes a control valve 11, a restriction part 12 provided downstream of the control valve 11, an upstream pressure sensor 13 for measuring a pressure P1 between the control valve 11 and the restriction part 12, a differential pressure sensor 20 for measuring a differential pressure ΔP between the upstream and the downstream of the restriction part 12, and an arithmetic control circuit 16 connected to the control valve 11, the upstream pressure sensor 13, and the differential pressure sensor 20.

A flow rate control apparatus can obtain a flow rate of a fluid passing through a downstream-side valve in a form in which noise is significantly reduced with little time delay, and has improved responsiveness. The flow rate control apparatus includes: a downstream-side valve flow rate meter that measures a downstream-side valve flow rate that is a flow rate of a fluid passing through a downstream-side valve; and an observer including a downstream-side valve flow rate estimation model that estimates the downstream-side valve flow rate on the basis of an input parameter that changes an opening degree of the downstream-side valve. The observer is configured so as to be fed back a deviation between the measured value of the downstream-side valve flow rate and the estimated value of the downstream-side valve flow rate.

In order to provide a flow rate control apparatus capable of reducing pressure loss due to a downstream valve while enhancing responsiveness in flow rate control, a controller is designed to control the downstream valve on the basis of a flow rate deviation when a valve opening of the downstream valve is smaller than a predetermined valve opening. The controller is designed to control an upstream valve on the basis of the flow rate deviation when the valve opening of the downstream valve is the predetermined valve opening or more.

The present invention provides methods for determining a parameter associated with a flow of a fluid located within a fluid conduit, based on measuring the difference between electrical signals of at least two second sensing elements contacting different positions on am exterior of the fluid conduit. The sensing elements comprise an assembly of nanoparticles being in electric contact with conductive electrodes; wherein the electrical signals of the sensing elements are responsive to at least one of pressure and temperature. Further provided is a clamping device configured to reduce a cross-sectional diameter of a portion of the fluid conduit, in order to determine said parameter.

A flowmeter includes at least one measuring tube, a measuring arrangement for measuring the flow of a medium flowing through the measuring tube, at least one receiving unit for a sensor unit and a sensor unit. The receiving unit is arranged on the measuring tube. The sensor unit includes at least one sensor, at least one flexible printed circuit board and at least one carrier. The at least one sensor is arranged on the at least one flexible printed circuit board. The sensor unit is plugged into the receiving unit. The at least one flexible printed circuit board is at least partially wrapped or folded around the carrier such that the sensor is arranged inside the measuring tube in the inserted state.