Dual function flow measurement apparatus having an array of sensors
View Patent ↗A dual function flow measurement apparatus is provided that combines the functionality of an apparatus that measures the speed of sound propagating through a fluid flowing within a pipe, and measures pressures disturbances (e.g. vortical disturbances or eddies) moving with a fluid to determine respective parameters of the flow propagating through a pipe. The apparatus includes a sensing device that includes an array of pressure sensors used to measure the acoustic and convective pressure variations in the flow to determine desired parameters. The measurement apparatus includes a processing unit the processes serially or in parallel the pressure signals provided by the sensing array to provide output signals indicative of a parameter of the fluid flow relating to the velocity of the flow and the speed of sound propagating through the flow, respectively.
1. An apparatus for measuring at least two parameters of a process flow flowing within a pipe, the apparatus comprising:
an array of non-intrusive sensors disposed at different axial locations along the pipe, each of the sensors providing a respective pressure signal indicative of a pressure disturbance within the pipe at a corresponding axial position,; and
a signal processor, responsive to said pressure signals, which provides a first signal indicative of a velocity of a pressure field moving with the process flow and provides a second signal indicative of a speed of sound propagating through the process flow.
2. The apparatus of claim 1 , wherein the processing unit includes a convective processing unit that determines the first signal and an acoustic processing unit that determines the second signal.
3. The apparatus of claim 2 , wherein the convective processing unit includes an array processor that determines power in the k-ω plane.
4. The apparatus of claim 3 , wherein the acoustic processing unit includes an array processor that determines power in the k-ω plane.
5. The apparatus of claim 2 , wherein the convective processing unit includes a convective ridge identifier that determines the convective ridge in the k-ω plane.
6. The apparatus of claim 5 , wherein the acoustic processing unit includes an acoustic ridge identifier that determines the acoustic ridge in the k-ω plane.
7. The apparatus of claim 2 , wherein the convective processing unit includes a first analyzer that determines a slope of the convective ridge to determine one of the velocity, the mach number, and volumetric flow rate of the process flow.
8. The apparatus of claim 2 , wherein the acoustic processing unit includes a second analyzer that determines a slope of the acoustic ridge to determine one of steam quality or “wetness”, vapor/mass ratio, liquid/solid ratio, volumetric flow rate, mass flow rate, average size of suspended particles, density, gas volume fraction, and enthalpy of the flow.
9. The apparatus of claim 1 , wherein the signal processor processes the respective pressure signals in parallel to simultaneously determine the first and second signals.
10. The apparatus of claim 1 , wherein the signal processor processes the respective pressure signals in series to sequentially determine the first and second signals.
11. The apparatus of claim 1 , wherein the processing unit includes a common data acquisition unit for digitizing the pressure signals.
12. The apparatus of claim 1 , wherein the processing unit includes a common array processor for determining the power in the k-ω plane for identifying both an acoustic ridge and convective ridge.
13. The apparatus of claim 1 , wherein the process flow is one of a single phase fluid and a multi-phase mixture.
14. The apparatus of claim 1 , wherein the pressure signals are indication of acoustic pressures propagating within the flow and unsteady pressures convecting with the flow.
15. The apparatus of claim 14 , wherein the unsteady pressures convecting with the flow are indication of vortical disturbances within the flow.
16. The apparatus of claim 1 , wherein the signal processor detennines the slope of at least one acoustic ridge in the k-ω plane to determine the speed of sound propagating through the flow, and the slope of a convective ridge in the k-ω plane to determine the velocity of the flow.
17. The apparatus of claim 1 , wherein the array of sensors include one of 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 and 20 sensors.
18. The apparatus of claim 1 , wherein the array of sensors include two sensors.
19. The apparatus of claim 1 , wherein the array of sensors include three sensors.
20. The apparatus of claim 1 , wherein the sensors include strain sensors andlor pressure sensors.
21. The apparatus of claim 1 , wherein the second signal is indicative of acoustic pressures propagating axially in one-dimension through the process fluid.
22. The apparatus of claim 1 , wherein the array of sensors are clamped onto the outside of the pipe.
23. The apparatus of claim 1 , wherein the array of sensors are attached onto the outside of the pipe.
24. The apparatus of claim 1 , wherein the sensors are formed of piezoelectric film material.
25. The method for measuring at least two parameters of a process flow flowing within a pipe, the method including comprising:
measuring non-intrusively pressure disturbances within the pipe at different axial locations along the pipe,
providing a respective pressure signal indicative of a pressure at a corresponding axial position; and
providing a velocity of a pressure field moving with the process flow and a speed of sound propagating through the process flow in response to the pressure signals.
26. The method of claim 25 , wherein the providing a velocity and a speed of sound is determined by processing the respective pressure signals in parallel to simultaneously determine the velocity and speed of sound.
27. The method of claim 25 , wherein the providing a velocity and a speed of sound is determined by processing the respective pressure signals in series to sequentially determine the velocity and speed of sound.
28. The method of claim 25 , wherein providing the velocity includes determining power in the k-ω plane.
29. The method of claim 28 , wherein providing the velocity includes determining a convective ridge in the k-ω plane.
30. The method of claim 28 , wherein providing the speed of sound includes determining an acoustic ridge in the k-ω plane.
31. The method of claim 25 , providing a velocity further includes determining a slope of a convective ridge to determine one of the velocity, the mach number, and volumetric flow rate of the process flow.
32. The method of claim 25 , providing a speed of sound further includes determining a slope of an acoustic ridge to determine one of steam quality or “wetness”, vapor/mass ratio, liquid/solid ratio, volumetric flow rate, mass flow rate, average size of suspended particles, density, gas volume fraction, and enthalpy of the flow.
33. The method of claim 25 , further includes digitizing the pressure signals.
34. The method of claim 25 , wherein the process flow is one of a single phase fluid and a multi-phase mixture.
35. The method of claim 25 , wherein the pressure signals are indication of acoustic pressures propagating within the flow and unsteady pressures convecting with the flow.
36. The method of claim 25 , wherein the unsteady pressures convecting with the flow are indication of vortical disturbances within the flow.
37. The method of claim 25 , wherein providing the velocity and speed of sound further includes determining the slope of at least one acoustic ridge in the k-ω plane to determine the speed of sound propagating through the flow, and the slope of a convective ridge in the k-ω plane to detennine the velocity of the flow.
38. The method of claim 25 , wherein the pressures are measured at 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 locations.
39. The method of claim 25 , wherein the pressures are measured at two locations.
40. The method of claim 25 , wherein the pressures are measured at three locations.
41. The method of claim 25 , wherein the pressures are measured using strain sensors and/or pressure sensors.
42. The method of claim 41 , wherein the sensors are clamped onto the outside of the pipe.
43. The method of claim 41 , wherein the sensors are attached onto the outside of the pipe.
44. The method of claim 41 , wherein the sensors are formed of piezoelectric film material.
45. The method of claim 25 , wherein the speed of sound is indicative of the velocity of acoustic pressures propagating axially in one-dimension through the process flow.