Multiphase flowmeters and related methods are disclosed herein. An example multiphase flowmeter includes a microwave transmitter to transmit a signal through a fluid, a microwave receiver to determine at least one of attenuation or phase shift, a sensor to obtain at least one of pressure, temperature, or differential pressure, an intermediate-output generator to determine intermediate flow parameters, and a flow rate generator to determine a flow rate for respective phases in the fluid, and a model selector to select at least one of a physics model or a machine learning model for determining the intermediate flow parameters or the flow rates, the physics model to determine a first value of the intermediate flow parameters or the flow rates, and, in response to an error not being less than a threshold, the machine learning model to determine a second value of the intermediate flow parameters or the flow rates.

A device for measuring flow rate of wet gas based on an exempt radioactive source, includes a section of cylindrical pipe and a conical throttle located inside the cylindrical pipe and coaxially arranged therewith. The conical throttle includes a head cone section and a tail cone section arranged to have a common bottom surface. The head cone section faces a wet gas inlet of the cylindrical pipe. An annular gap is defined between the inner wall of the cylindrical pipe and the maximum diameter of the conical throttle for passage of wet gas. An exempt radioactive source block is arranged at the maximum diameter of the conical throttle in such a way that the gamma rays emitted from the radioactive source block can transmit radially through the annular gap to reach the gamma ray detector located outside the cylindrical pipe.

A device for measuring flow rate of wet gas based on an exempt radioactive source, includes a section of cylindrical pipe and a conical throttle located inside the cylindrical pipe and coaxially arranged therewith. The conical throttle includes a head cone section and a tail cone section arranged to have a common bottom surface. The head cone section faces a wet gas inlet of the cylindrical pipe. An annular gap is defined between the inner wall of the cylindrical pipe and the maximum diameter of the conical throttle for passage of wet gas. An exempt radioactive source block is arranged at the maximum diameter of the conical throttle in such a way that the gamma rays emitted from the radioactive source block can transmit radially through the annular gap to reach the gamma ray detector located outside the cylindrical pipe.

A method for estimating a flow rate of a material (e.g., a multiphase fluid) may include: flowing the material through one or more of a plurality of receptacles of a dielectric contrast analysis structure that includes: a bulk dielectric substance and the plurality of receptacles in the bulk dielectric substance; exposing the dielectric contrast analysis structure to incident electromagnetic radiation; detecting and analyzing a resultant electromagnetic radiation from the exposed dielectric contrast analysis structure to yield a phase fraction in the material and a phase distribution in the material; measuring a differential pressure across the dielectric contrast analysis structure; and estimating the flow rate of the material using the differential pressure, the phase fraction, and the phase distribution in the material.

A method for estimating a flow rate of a material (e.g., a multiphase fluid) may include: flowing the material through one or more of a plurality of receptacles of a dielectric contrast analysis structure that includes: a bulk dielectric substance and the plurality of receptacles in the bulk dielectric substance; exposing the dielectric contrast analysis structure to incident electromagnetic radiation; detecting and analyzing a resultant electromagnetic radiation from the exposed dielectric contrast analysis structure to yield a phase fraction in the material and a phase distribution in the material; measuring a differential pressure across the dielectric contrast analysis structure; and estimating the flow rate of the material using the differential pressure, the phase fraction, and the phase distribution in the material.

A self-correcting pressure-based mass flow control apparatus includes outlet pressure sensing to enable correction for non-ideal operating conditions. Further the mass flow control apparatus having a fluid pathway, a shutoff valve in the fluid pathway, a reference volume in the fluid pathway, a first pressure measuring sensor in fluid communication with the reference volume, a first temperature measuring sensor providing a temperature signal indicative of the fluid temperature within the reference volume, a proportional valve in the fluid pathway, and a second pressure measuring sensor in fluid communication with the fluid pathway.

A self-correcting pressure-based mass flow control apparatus includes outlet pressure sensing to enable correction for non-ideal operating conditions. Further the mass flow control apparatus having a fluid pathway, a shutoff valve in the fluid pathway, a reference volume in the fluid pathway, a first pressure measuring sensor in fluid communication with the reference volume, a first temperature measuring sensor providing a temperature signal indicative of the fluid temperature within the reference volume, a proportional valve in the fluid pathway, and a second pressure measuring sensor in fluid communication with the fluid pathway.

Mass flow controllers that can provide for improved bleeding time and can be manufactured with less complexity and cost are provided. A mass flow controller includes a body having a valve outlet bore defining a flow path and an adjustable valve configured to control flow of a gas through the flow path. A valve element includes an outlet orifice of the adjustable valve and is disposed within the bore. The mass flow controller further includes a pressure drop element disposed coaxially with the valve element within the bore. An upstream pressure sensor is configured to detect a pressure at a location in the flow path between the adjustable valve and the pressure drop element, and a controller is configured to determine a flow rate through the flow path based on pressure as detected by the upstream pressure sensor.

Mass flow controllers that can provide for improved bleeding time and can be manufactured with less complexity and cost are provided. A mass flow controller includes a body having a valve outlet bore defining a flow path and an adjustable valve configured to control flow of a gas through the flow path. A valve element includes an outlet orifice of the adjustable valve and is disposed within the bore. The mass flow controller further includes a pressure drop element disposed coaxially with the valve element within the bore. An upstream pressure sensor is configured to detect a pressure at a location in the flow path between the adjustable valve and the pressure drop element, and a controller is configured to determine a flow rate through the flow path based on pressure as detected by the upstream pressure sensor.

A mud flow measurement system includes a flow pipe, a Coriolis meter, a differential pressure sensor, and a mud flow measurement module. The mud flow measurement module is configured to select a calibration curve corresponding to a drilling mud injected into the well, determine a measured density based on the signal from each of the vibration sensors and the selected calibration curve, determine a differential pressure across the Coriolis meter from the differential pressure sensor, and compute a calculated mass flow rate, Q.sub.mass, of the multiphase mud flow using equation

[00001]$Q_{\mathrm{mass}}=\frac{C_d{A}_t}{\sqrt{1-{\beta }^4}}\sqrt{2\rho *\Delta P},$

where C.sub.d is a calibration constant, A.sub.t is a cross-sectional area of the measurement tube, β is a ratio of the internal diameters of the flow pipe the measuring tube, ρ is the density of the multiphase mud, and ΔP is the differential pressure across the Coriolis meter, where ρ is the measured density determined from the Coriolis meter.