A flow rate control device 100 includes a control valve 6 provided in a flow path 1, a flow rate measurement unit 2, 3 for measuring fluid flow rate controlled by the control valve 6, and a controller 7. The controller 7 is configured so as to control the opening/closing operation of the control valve 6 to match the measurement integral flow rate based on the signal outputted from the flow rate measurement unit (Vn+Vd) to the target integral flow rate Vs.

The flow rate measurement method includes: measuring a first pressure of a gas filled in a first flow path connected to a flow rate controller and a second flow path connected to the first flow path; supplying a gas to the first and second flow paths via the flow rate controller and measuring a second pressure and a temperature of the gas filled in the first and second flow paths; after the gas is exhausted from the second flow path, measuring a third pressure of the gas filled in the second flow path; measuring a fourth pressure of the gas filled in the first and second flow paths; and calculating an amount of the gas supplied to the first and second flow paths via the flow rate controller, based on the first, second, third, and fourth pressures and the temperature.

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.

A sensor apparatus may include a channel structure configured to couple with an external element and a fluid conduit, such that the channel structure may receive a fluid, at least partially drawn through the external element from an ambient environment, and direct the fluid through the fluid conduit. A sensor may generate sensor data indicating a flow rate of the fluid through the fluid conduit based on monitoring a variation in a pressure at a location in hydrodynamic contact with the fluid conduit and in relation to an ambient pressure of the ambient environment. The sensor apparatus may enable generation of improved topography information associated with flows of fluid drawn from the external element based on measuring a local pressure at the location in hydrodynamic contact with the fluid conduit and determining the ambient pressure based on monitoring the local pressure over time.

The present disclosure relates to a method for determining a volumetric and/or mass flow rate of a medium flowing in a tube, wherein a density and/or a viscosity of the fluid is/are determined using a MEMS sensor chip, wherein the medium flowing in the tube at least partially flows through a measuring channel of the MEMS sensor chip to determine the density and/or the viscosity of the fluid, and wherein the volumetric and/or mass flow rate of the medium is determined regardless of the medium based on a detected pressure drop over the measuring channel of the MEMS sensor chip and the density and/or viscosity determined by the MEMS sensor.

A wet gas flow meter includes an input pipe section; a vibration measurement pipe; an output pipe section; a differential pressure sensor; a pressure sensor; a transducer; and a temperature sensor. The input pipe section, the vibration measurement pipe, and the output pipe section are connected sequentially one by one. The input pipe section includes a first pressure tap, and the output pipe section include a second pressure tap; the differential pressure sensor communicates with the input pipe section and the output pipe section via the first pressure tap and the second pressure tap, respectively. The pressure sensor communicates with the input pipe section and/or the output pipe section via the first pressure tap and/or the second pressure tap, respectively. The transducer is disposed on the vibration measurement pipe. The temperature sensor is disposed on the vibration measurement pipe and/or the input pipe section and/or the output pipe section.

A method for calibrating a product fluid flow valve disposed along a flow path in a site duct, and including damper blades, an actuator coupled thereto, a differential pressure sensor, and a blade controller adapted to define adjustable product flow apertures, comprising the steps: with a calibration fluid flow valve in a calibration duct remote from the product fluid flow valve, and characterized by a geometric shape and operational parameters corresponding to those of the product fluid flow valve, and with a calibration controller, establishing a plurality of calibration conditions including pressure drop across the calibration blades and area of the calibration apertures, determining a calibration flow rate (CFM) function, transferring the CFM function to the product blade controller and adjusting the adjustable product flow apertures so that a parameter set point is attained. In a form, fluid flowing through the product flow apertures forms a vena contracta.

In some examples, a pressure reducing valve includes a valve body defining a defining a flow path and a restricting element within the flow path. A sensing element is configured to modify a position of the restricting element in the flow path. The sensing element defines a first area in fluid communication with the flow path and a second area fluidly isolated from the flow path. The pressure reducing valve includes control circuitry configured to determine a differential pressure over a section of the flow path, determine a position of the restricting element, and determine a flow rate based on the differential pressure and the position of the restricting element.

A method for diagnosing a differential pressure line of a differential pressure measurement arrangement includes capturing a first set number of differential pressure values, which represent a difference between a first media pressure and a second media pressure within a process, and checking whether the differential pressure measurement arrangement and/or the process are in a state that allows a diagnosis of the differential pressure line. Where it is determined that the differential pressure measurement arrangement and/or the process are not in a state that allows a diagnosis of the differential pressure line, the differential pressure values are captured anew such that the previously captured differential pressure values are deleted or overwritten. Otherwise, a diagnostic function to determine whether a differential pressure line is blocked is carried out.

A gas flow control system for delivering a plurality of gas flows. The gas flow control system has a gas flow path extending from a gas inlet to first and second gas outlets. First and second flow restrictors are operably coupled to the gas flow path. First and second valves are operably coupled to the gas flow path such that when both first and second valves are in a fully open state, flows of gas from the first and second gas outlets are split according to the impedances of the first and second flow restrictors.