Review of measurement techniques for void fraction of two-phase flow through annulus

Apparatus and method for ultrasonic flow metering of viscous fluids. In one embodiment, an ultrasonic flow metering system includes an ultrasonic flow meter, a flow conditioner, and a reducer. The ultrasonic flow meter includes a pair of ultrasonic transducers arranged to exchange ultrasonic signals through a fluid stream flowing between the transducers. The flow conditioner is disposed upstream of the ultrasonic flow meter. The reducer is disposed between the flow conditioner and the ultrasonic flow meter to reduce the cross sectional area of the fluid stream flowing from the flow conditioner to the ultrasonic flow meter.

Ultrasonic flow metering with laminar to turbulent transition flow control

Crossover of active materials in an electrochemical cell can detrimentally impact operating performance, particularly for flow batteries. Flow batteries with tolerance toward crossover of active materials can incorporate a first half-cell containing a first electrolyte solution that includes a coordination complex as a first active material, and a second half-cell containing a second electrolyte solution that includes an unbound form of an organic compound as a second active material. The coordination complex contains a redox-active metal center and an organic compound bound to the redox-active metal center. The unbound form of the organic compound in the second electrolyte solution is the same as the bound organic compound in the first electrolyte solution, or an oxidized or reduced variant thereof. Catechol and substituted catechols can be particularly desirable organic compounds for inclusion in the coordination complex and the second electrolyte solution.

Mitigation of crossover within flow batteries

Disclosed is a pipe internal-phase separation type high-gas-containing-rate gas-liquid two-phase fluid flow measurement device and method. The pipe internal-phase separation type high-gas-containing-rate gas-liquid two-phase fluid flow measurement device is mainly formed by a pipe, an inner pipe, a two-stage cyclone, a reducing pipe, a cyclone pipe, a transition pipe, an increasing pipe, a cyclone elimination device, a small conventional separator, a gas flow meter and a liquid flow meter. A pipe internal-phase separation technology is adopted in the pipe internal-phase separation type high-gas-containing-rate gas-liquid two-phase fluid flow measurement method and matched with the gravity and centrifugal separation effect, the complete separation of the gas-liquid two-phase fluid in the pipe is achieved through a plurality of separation steps, and the flow rate of a gas phase and the flow rate of a liquid phase are measured through the gas flow meter and the liquid flow meter respectively. According to the pipe internal-phase separation type high-gas-containing-rate gas-liquid two-phase fluid flow measurement device and method, the size of a separation method type gas-liquid two-phase flow measurement device can be greatly reduced, the real-time performance of the measurement is improved, the manufacturing cost can be significantly reduced, and the pipe internal-phase separation type high-gas-containing-rate gas-liquid two-phase fluid flow measurement device and method can be convenient for wide application to the engineering.

Pipe internal-phase separation type high-gas-containing-rate gas-liquid two-phase fluid flow measurement device and method

The invention relates to a device for online measurement of gas-phase flux and liquid-phase flux of moisture in a horizontal pipe. The device comprises a horizontal venturi pipe and a gamma ray detector. The horizontal venturi pipe comprises a frustum-shaped inlet channel with section area reduced gradually, a cylindrical throat channel and a frustum-shaped outlet channel with section area increased gradually. The gamma ray detector comprises a gamma ray emitter and a gamma ray inspection device, with the arrangement mode of the gamma ray emitter and a gamma ray inspection device, gamma rays emitted by the gamma ray emitter can radially penetrate along the cross section of the throat channel to reach a gamma ray receiver. The invention further relates to a method for measuring the gas-phase flux and the liquid-phase flux of the moisture in the horizontal pipe by using the device.

Device and method for online measurement of gas-phase flux and liquid-phase flux of moisture in horizontal pipe

A flow meter apparatus and method are presented for measuring a flow rate of a multiphase fluid mixture comprising at least one gas phase and one liquid phase. The flow meter comprises a pipe section and measurement section through which the mixture flows. The flow meter also comprises a fraction measurement device adapted to estimate a representative fraction of the gas phase and/or liquid phase of the mixture passing at the measurement section. Moreover, the flow meter preferably comprises at least one ultrasonic sensor arranged to estimate a characteristic, such as liquid film thickness or velocity, of a portion of the liquid phase flowing as liquid film along a wall of the pipe section. The characteristic is preferably used to correct the estimated representative fraction of the gas phase and/or liquid phase when the gas phase flows in a core of the pipe section, and a portion of the liquid phase flows partially as liquid film along the wall of the pipe section and another portion of the liquid phase flows partially as liquid droplets in the core of the pipe section.

A multiphase flowmeter and liquid film measurement method

An apparatus (1 ) for measuring at least one characteristic value of a multiphase fluid mixture (13) comprises: a pipe section (20) having a main flow path through which the multiphase fluid mixture (13) flows, the main flow path comprising a throat (22) between an upstream part (21) and a downstream part (23) of the main flow path such as to generate a pressure drop between the upstream part (21 ) and the downstream part (23); a first sensing arrangement (28, 33, 29, 34, 35, 36) to measure a first characteristic value of the multiphase fluid mixture (13) flowing into the main flow path; -a channel (25) being positioned within the wall of the pipe section (20) such as to maintain similar operating conditions as in the main flow path, the channel (25) being coupled to the main flow path by an inlet (24) at the upstream part (21 ), or the throat (22), and by an outlet (26) at the downstream part (23), or the throat (22), such that the pressure drop generates an aspiration effect diverting a sample of the multiphase fluid mixture (13) flowing through the main flow path into the channel (25), the channel (25) having an internal diameter (70) such that said multiphase fluid mixture sample flows in successive separated enriched phase samples (42, 52) within the channel (25); and a second sensing arrangement (30) to measure a second characteristic value of one of the phase of the multiphase fluid mixture sample flowing into the channel (25).

An apparatus for measuring at least one characteristic value of a multiphase fluid mixture

A reference measurement apparatus for a multiphase flow meter comprising: a sampling and measuring chamber coupled to a sampling port via a sample transfer line for extracting the sample having at least one of the gas phase and the liquid phase from the multiphase fluid mixture flowing through the pipe section; a pressure and temperature regulation arrangement arranged to maintain the sample from the sampling port to the sampling and measuring chamber at a pressure/temperature substantially similar to the pressure/temperature of the multiphase fluid mixture flowing through the pipe section; and a second fraction measurement device arranged to estimate a linear attenuation related to the at least one of the gas phase and the liquid phase extracted from the sample, said linear attenuation being used to correct the estimated representative fraction for the at least one of the gas phase and the liquid phase of the multiphase fluid mixture.

A multiphase flowmeter and a correction method for such a multiphase flowmeter

Both a flow meter system and method are provided for accurately measuring the percentage amounts of liquid and gas phases in a multiphase flow through a conduit when the liquid phase constitutes a small minority portion (e.g., less than about 20%) of the multiphase flow. The system includes a flow meter that includes a differential pressure sensor connected across a Venturi in the conduit, and a dual energy fraction meter, each of which is operably connected to a digital processor. The system further includes a pump connected to the conduit upstream of the flow meter that introduces at least one pulse of a known quantity of liquid, the pulse being sufficient in volume to temporarily increase the liquid phase by a detectable amount. After the liquid pulse is introduced into the multiphase flow, the digital processor computes the changes in the percentage amounts of the liquid and gas phases which should have occurred as a result of the pulse, and compares the computed changes with the actual changes measured by the flow meter in order to calibrate the flow meter. The measured increase in the liquid flow is then subtracted from the total measured liquid flow to determine the actual percentage of liquid flow.

Andrew Charles Baker

Papers

A multiphase flowmeter and liquid film measurement method

An apparatus for measuring at least one characteristic value of a multiphase fluid mixture

A multiphase flowmeter and a correction method for such a multiphase flowmeter

Flow meter system and method for measuring an amount of liquid in a largely gaseous multiphase flow