There is provided a fluid sensing apparatus comprising a fluid flow channel, at least one fluid conduit in fluid communication with the fluid flow channel, and a fluid sensor having a casing and at least one sensor port in fluid communication with the at least one fluid conduit and providing access into the casing. The fluid sensing apparatus also includes a pressure compensation chamber in which the casing of the fluid sensor is enclosed. The apparatus further includes at least one pressure compensation conduit in fluid communication with the pressure compensation chamber and with the fluid flow channel. Also provided is a mass flow controller including such a fluid sensing apparatus.

There is provided a fluid sensing apparatus comprising a fluid flow channel, at least one fluid conduit in fluid communication with the fluid flow channel, and a fluid sensor having a casing and at least one sensor port in fluid communication with the at least one fluid conduit and providing access into the casing. The fluid sensing apparatus also includes a pressure compensation chamber in which the casing of the fluid sensor is enclosed. The apparatus further includes at least one pressure compensation conduit in fluid communication with the pressure compensation chamber and with the fluid flow channel. Also provided is a mass flow controller including such a fluid sensing apparatus.

Geothermal two-phase flow metering device and measurement method in geothermal well and large diameter pipelines are disclosed herein. The method thereof is measuring the enthalpy and mass flow rate of the two-phase fluid in real-time. The device mainly includes a primary, a secondary and a multi-tapping pressure components. The primary component can be an Orifice plate or Nozzle or Venturi tube. The secondary component is a transmitters-transducers. The multi tapping pressure used are radius, flanges, and corners. The example system includes data signal of upstream pressure, downstream and the pressure difference of the multi tapping is recorded and calculated in the flow computer machine. A flow meter has good accuracy with less noise for a wide range of wells output and pipeline size range, which is very useful for the geothermal industry.

A system and method for dividing a single mass flow into secondary flows of desired ratios to total flow. Each secondary flow line includes a pressure drop element, an absolute pressure sensor and a differential pressure sensor. The nonlinear relationship between flow and pressures can be transformed into a function of the absolute and differential pressures that has a linear relationship with the flow.

A control unit 3 of a flow rate control system 1 comprises: a recording unit 31 for recording measured values of a pressure sensor P and a temperature sensor T, a storage unit 32 for storing volume data between a first valve V1 and a second valve V2 corresponding to the measured value of the pressure sensor P, and an arithmetic unit 33 for calculating a flow rate based on a first pressure value P1 and a first temperature value T1 measured after opening the first valve V1 and the second valve V2 to flow a gas and then closing the first valve V1 and the second valve V2 simultaneously in a state where the gas is flowing; a second pressure value P2 and a second temperature value T2 measured after opening the first valve V1 and the second valve V2 to flow a gas, closing the second valve V2 in a state where the gas is flowing, and then closing the first valve V1 after a predetermined time Δt has elapsed; and a volume value V between the first valve V1 and the second valve V2 which corresponds to the second pressure value P2.

A control unit 3 of a flow rate control system 1 comprises: a recording unit 31 for recording measured values of a pressure sensor P and a temperature sensor T, a storage unit 32 for storing volume data between a first valve V1 and a second valve V2 corresponding to the measured value of the pressure sensor P, and an arithmetic unit 33 for calculating a flow rate based on a first pressure value P1 and a first temperature value T1 measured after opening the first valve V1 and the second valve V2 to flow a gas and then closing the first valve V1 and the second valve V2 simultaneously in a state where the gas is flowing; a second pressure value P2 and a second temperature value T2 measured after opening the first valve V1 and the second valve V2 to flow a gas, closing the second valve V2 in a state where the gas is flowing, and then closing the first valve V1 after a predetermined time Δt has elapsed; and a volume value V between the first valve V1 and the second valve V2 which corresponds to the second pressure value P2.

A mass flow meter includes an arcuate tube section that is semi-circular, an inner pressure sensor disposed on an inner curvature portion of the arcuate tube section and configured to capture an inner pressure measurement of the flowing fluid, an outer pressure sensor disposed on an outer curvature portion of the arcuate tube section and configured to capture an outer pressure measurement of the flowing fluid, and processing circuitry. The processing circuitry may be configured to receive the inner pressure measurement and the outer pressure measurement, determine a pressure difference between the inner pressure measurement and the outer pressure measurement, and determine a mass flow rate of the flowing fluid passing through the arcuate tube section based on the pressure difference and a fluid density of the flowing fluid.

A flow measurement apparatus can include a main flow passage, a bypass flow passage having an inlet and an outlet connected with the main flow passage, a mass flowmeter connected in the bypass flow passage between the inlet and the outlet, and a flow restrictor connected in the bypass flow passage between the inlet and the outlet. A method can include connecting the flow measurement apparatus, so that a fluid flow in the well also flows through the flow measurement apparatus, and determining at least one rheological parameter of a non-Newtonian fluid, based on an output of the flow measurement apparatus.

A flow measurement apparatus can include a main flow passage, a bypass flow passage having an inlet and an outlet connected with the main flow passage, a mass flowmeter connected in the bypass flow passage between the inlet and the outlet, and a flow restrictor connected in the bypass flow passage between the inlet and the outlet. A method can include connecting the flow measurement apparatus, so that a fluid flow in the well also flows through the flow measurement apparatus, and determining at least one rheological parameter of a non-Newtonian fluid, based on an output of the flow measurement apparatus.

Systems and methods for detecting a composition of a binary gas mixture are provided. Such methods and systems include, with a species-dependent mass flow meter, sensing a mass flow rate of a binary gas mixture comprising gases of differing gas correction factors and, with a species-independent pressure sensor, sensing a total pressure of the binary gas mixture. An output representative of a relative concentration of one gas of the binary gas mixture is provided. The relative concentration is determined as a function of the sensed mass flow rate and the sensed total pressure.