초록 ▼

The present invention relates to a dual velocity method and apparatus for measuring flow rate of a fluid, independent of flow regime, the fluid having a plurality of components, at least one of which is capable of existing in an oil continuous phase emulsion in a conduit. The present invention only

The present invention relates to a dual velocity method and apparatus for measuring flow rate of a fluid, independent of flow regime, the fluid having a plurality of components, at least one of which is capable of existing in an oil continuous phase emulsion in a conduit. The present invention only measures component fluid flow rates for components of the fluid which may include at least an oil continuous phase emulsion, but not a component including a water continuous phase emulsion. Velocity slip is directly determined by cross correlations of fluid electrical property signals which are used to measure the two most predominant velocities in a multiphase velocity distribution. Furthermore, phase velocity measurements are further improved by cross correlating signals from a pair of downstream sensors which are shifted a predetermined radial angle offset from corresponding pair of upstream diametrically positioned sensors.

대표청구항 ▼

What is claimed is: 1. A method for measuring flow rate of a fluid within a conduit, independent of flow regime, the fluid having a plurality components where at least one of the plurality of components is capable of existing in an oil continuous phase emulsion in the conduit, the method comprising

What is claimed is: 1. A method for measuring flow rate of a fluid within a conduit, independent of flow regime, the fluid having a plurality components where at least one of the plurality of components is capable of existing in an oil continuous phase emulsion in the conduit, the method comprising: a. measuring four separate fluid electrical properties using a plurality of sensors; b. outputting the measured fluid electrical properties to a calculator; c. optimizing accuracy of the measured fluid electrical property signals; d. determining a dispersed phase fluid velocity by cross-correlating a first periodic signal from a first pair of sensors with a second periodic signal from a second pair sensors; e. determining a free gas slug velocity by cross-correlating a periodic signal from a third pair of sensors with a periodic signal from a fourth pair of sensors; f. determining a water cut, at a first predetermined period of time, using a first predetermined mathematical relationship between the measured fluid electrical property signals and fraction of water in a dispersed phase; g. determining a dispersed gas fraction, at a second predetermined period of time, using a second predetermined mathematical relationship between the measured fluid electrical property signals; h. determining a dispersed water fraction, at a third predetermined period of time, using a third predetermined mathematical relationship between the determined dispersed gas fraction and the determined water cut; i. determining a free gas fraction, at a fourth predetermined period of time, using a fourth predetermined mathematical relationship between the measured fluid electrical property signals; j. determining, at a fifth predetermined period of time, a fraction of time in which fluid flow is in slug flow; k. determining a fluid component volumetric flow rate using a fifth predetermined mathematical relationship between the component phase fractions, the fraction of time the fluid is in slug flow, and a predetermined conduit characteristic; and l. outputting the fluid component volumetric flow rate to at least one of a calculator, a computer, a display and a printer. 2. The method of claim 1, wherein measuring the four separate fluid electrical properties further comprises: a. measuring the first fluid electrical property upstream signal from a first pair of near conduit wall sensitive, diametrically positioned sensors; b. measuring the second fluid electrical property signal from a second pair of near conduit wall sensitive, diametrically positioned sensors positioned a first predetermined distance downstream from the first pair of near conduit wall sensitive diametrically positioned sensors; c. measuring the third fluid electrical property upstream signal from a first pair of conduit cross-sectional sensitive, diametrically positioned sensors; and d. measuring the fourth fluid electrical property signal from a second pair of conduit cross-sectional sensitive, diametrically positioned sensors positioned a second predetermined distance downstream from the first pair of cross-sectional conduit sensitive diametrically positioned sensors. 3. The method of claim 2, wherein: a. the dispersed phase fluid velocity is determined by cross-correlating a periodic signal from the first pair of near conduit wail sensitive diametrically positioned sensors with a periodic signal from the second pair of near conduit wall sensitive diametrically positioned sensors; and b. the free gas slug velocity is determined by cross-correlating a periodic signal from the first pair of cross-sectional conduit sensitive diametrically positioned sensors with a periodic signal from the second pair of cross-sectional conduit sensitive diametrically positioned sensors. 4. The method of claim 1, further comprising outputting the fluid component volumetric flow rate to at least one of (a) another process, (b) a display, or (c) a printer. 5. The method of claim 1, wherein determination of the water cut is optimized by at least one of (i) a predetermined offset value, (ii) a predetermined calibration method, or (iii) a time series analysis. 6. The method of claim 1, wherein the accuracy of the measured fluid electrical properties is optimized by using small electrode spatial filtering near a periphery of an interior of the conduit. 7. A dual velocity method for measuring flow rate of a fluid, independent of flow regime, the fluid comprising a plurality of components, at least one of the plurality of components being capable of existing in an oil continuous phase emulsion in a conduit, the method comprising: a. measuring, at a first predetermined time, a first fluid electrical property upstream signal from a first pair of near conduit wall sensitive, diametrically positioned sensors; b. measuring, at a second predetermined time, a second fluid electrical property signal from a second pair of near conduit wall sensitive, diametrically positioned sensors positioned a first predetermined distance downstream from the first pair of near conduit wall sensitive diametrically positioned sensors; c. measuring, at a predetermined time, a third fluid electrical property upstream signal from a first pair of conduit cross-sectional sensitive, diametrically positioned sensors; d. measuring, at a predetermined time, a fourth fluid electrical property signal from a second pair of conduit cross-sectional sensitive, diametrically positioned sensors positioned a second predetermined distance downstream from the first pair of cross-sectional conduit sensitive diametrically positioned sensors; e. optimizing the accuracy of the measured fluid electrical property signals; f. determining a water cut, at a predetermined period of time, using a first predetermined mathematical relationship between the measured fluid electrical property signals and a fraction of water in a dispersed phase; g. determining a dispersed phase fluid velocity by cross-correlating a periodic signal from the first pair of near conduit wall sensitive diametrically positioned sensors with a periodic signal from the second pair of near conduit wall sensitive diametrically positioned sensors; h. determining a free gas slug velocity by cross-correlating a periodic signal from the first pair of cross-sectional conduit sensitive diametrically positioned sensors with a periodic signal from the second pair of cross-sectional conduit sensitive diametrically positioned sensors; i. determining a dispersed gas fraction, at a predetermined period of time, using a second predetermined mathematical relationship between the measured fluid electrical property signals; j. determining a dispersed water fraction, at a predetermined period of time, using a third predetermined mathematical relationship between the dispersed gas fraction and the water cut; k. determining a free gas fraction, at a predetermined period of time, using a fourth predetermined mathematical relationship between the measured fluid electrical property signals; l. determining a fraction of time during which fluid flow is in slug flow; m. determining a fluid component volumetric flow rate using a fifth predetermined mathematical relationship between the component phase fractions, the fraction of time the fluid is in slug flow, and a predetermined conduit characteristic; and n. outputting the fluid component volumetric flow rate to at least one of a calculator, a computer, a display and a printer. 8. The method of claim 7, further comprising outputting the fluid component volumetric flow rate to at least one of (a) another process, (b) a display, or (c) a printer. 9. The method of claim 7 wherein at least one measurement of a fluid electrical property signal occurs at least one of (i) continuously or (ii) substantially continuously. 10. The method of claim 7, wherein: a. The first mathematical equation is b. The second mathematical equation is c. The third mathematical equation is βD=(1-αD)*βL; and d. The fourth mathematical equation is 11. The method of claim 7 further comprising shifting a second pair of diametrically positioned sensors a predetermined radial angle offset from the upstream first pair of diametrically positioned sensors. 12. The method of claim 11, wherein the predetermined radial angle offset is ninety degrees. 13. The method of claim 7, wherein the determination of water cut is optimized by at least one of (i) a predetermined offset value, (ii) a predetermined calibration method, or (iii) a time series analysis. 14. The method of claim 7, wherein the accuracy of the measured fluid electrical properties is optimized by using small electrode spatial filtering near a periphery of the interior of the conduit. 15. The method of claim 7, wherein: a. the volume flow rate of gas is calculated using the formula b. the volume flow rate of total liquid is calculated as c. the volume flow rate of water and oil is calculated using the formula QW=βL*QL; and d. the volume flow rate of oil is calculated using the formula QO=(1-βL)*QL. 16. A flow meter apparatus adapted to measure a flow rate of a fluid in a conduit, independent of flow regime, the fluid having a plurality of components, at least one of the plurality of components being capable of existing in an oil continuous phase emulsion, the flow meter apparatus comprising: a. a through-piece comprising a predetermined length and adapted to be attached longitudinally to a conduit; b. a first pair of near conduit wall sensitive, diametrically positioned sensors adapted to detect a first predetermined electrical property of a fluid within the conduit; c. a second pair of near conduit wall sensitive, diametrically positioned sensors adapted to detect a second predetermined electrical property of the fluid within the conduit, the second pair of near wall, diametrically positioned sensors being positioned a first predetermined distance from the first pair of the near wall, diametrically positioned sensors; d. a first pair of conduit cross-sectional sensitive, diametrically positioned sensors adapted to detect a third predetermined electrical property of the fluid within the conduit; and e. a second pair of conduit cross-sectional sensitive, diametrically positioned sensors adapted to detect a fourth predetermined electrical property of the fluid within the conduit, the second pair of cross-sectional, diametrically positioned sensors being positioned a second predetermined distance from the first pair of the cross-sectional, diametrically positioned sensors; and f. a sensor housing disposed at least partially circumferentially about a predetermined portion of the through-piece, the sensor housing adapted to provide access into an interior wall of the conduit for the sensors, the sensor housing further adapted to electrically insulate the sensors from the sensor housing. 17. The apparatus of claim 16, wherein then through-piece is attached to the conduit by at least one of (i) a flange or (ii) a weld.