Ultrasonic flow velocity measuring device and method

Abstract

The present invention relates to gas flow velocity measurement, and specifically provides an ultrasonic flow velocity measurement device and method. The measurement device includes an analysis unit, a first transducer, a second transducer, and a carrier. The first transducer and the second transducer are respectively arranged on the carrier; it further includes: a driving unit for driving the carrier to rotate, and the rotation angle θ satisfies: θ = arccos[(cosθ0) / k] - θ0, where k ≥ cosθ0; θ0 is the included angle between the initial position of the carrier in the measurement environment and the flow velocity, and k is the ratio of the range corresponding to the adjusted position of the carrier to the range corresponding to the initial position; if the angle θ is positive, the included angle between the carrier and the flow velocity becomes larger, and if the angle θ is negative, the included angle between the carrier and the flow velocity becomes smaller. The present invention has advantages such as accurate measurement.

Description

Technical Field

[0001] The present invention relates to flow velocity detection, and particularly to an ultrasonic flow velocity measuring device and method. Background Art

[0002] For the measurement of ultrasonic flow velocity of flue gas, a pair of transducers need to be fixed on a long rod and inserted deep into the flue or chimney. If the long rod is inserted horizontally, there is no air flow in the horizontal direction of the chimney, and the flue gas flow velocity cannot be effectively measured. Therefore, it needs to be installed at a certain downward inclination angle.

[0003] Currently, most products for measuring ultrasonic flow velocity of flue gas adopt the fixed 45 ° angle solution. However, 45 ° is only the optimal angle at medium wind speeds. At lower or higher wind speeds, the measurement accuracy and range are not optimal.

[0004] Some products directly align the probe direction with the flue gas direction, that is, the angle is 0. Although the 0 - angle solution can improve the measurement accuracy, the range may be insufficient at higher wind speeds. Moreover, the two transducers of the ultrasonic flow meter directly face the air flow direction, which will block the air flow and cause a large error in the measurement result.

[0005] As can be seen from the above, when the angle of the flue gas ultrasonic flow meter product is fixed, the corresponding range and accuracy are fixed. When the flow velocity changes, neither the accuracy nor the range is optimal. Summary of the Invention

[0006] To solve the deficiencies in the above - mentioned prior - art solutions, the present invention provides an ultrasonic flow velocity measuring device.

[0007] The object of the present invention is achieved by the following technical solutions:

[0008] An ultrasonic flow velocity measuring device, comprising an analysis unit, a first transducer, a second transducer, and a carrier. The first transducer and the second transducer are respectively arranged on the carrier; the ultrasonic flow velocity measuring device further comprises:

[0009] A driving unit, which is used to drive the carrier to rotate, and the rotation angle θ satisfies:

[0010] θ = arccos[(cosθ0) / k] - θ0, k ≥ cosθ0;

[0011] θ0 is the included angle between the initial position of the carrier in the measurement environment and the flow velocity, and k is the ratio of the range corresponding to the adjusted position of the carrier to the range corresponding to the initial position; if the angle θ is positive, the included angle between the carrier and the flow velocity becomes larger, and if the angle θ is negative, the included angle between the carrier and the flow velocity becomes smaller.

[0012] Another object of the present invention is to provide an ultrasonic flow velocity measurement method, and this object of the invention is achieved by the following technical solutions:

[0013] The ultrasonic flow velocity measurement method includes the following steps:

[0014] (A1) Determine whether the range corresponding to the current carrier position meets the flow velocity requirement output by the analysis unit;

[0015] If the result is negative, the judgment unit sends a carrier position adjustment instruction to the controller;

[0016] The carrier is arranged in the measurement environment, and the first transducer and the second transducer are respectively arranged on the carrier;

[0017] (A2) The controller calculates the rotation angle θ of the carrier according to the adjustment instruction and transmits it to the drive unit;

[0018] θ = arccos[(cosθ0) / k] - θ0, k ≥ cosθ0;

[0019] θ0 is the included angle between the initial position of the carrier in the measurement environment and the flow velocity, and k is the ratio of the range corresponding to the adjusted position of the carrier to the range corresponding to the initial position; if the angle θ is positive, the included angle between the carrier and the flow velocity becomes larger, and if the angle θ is negative, the included angle between the carrier and the flow velocity becomes smaller;

[0020] (A3) The drive unit drives the carrier to rotate, and the rotation angle is θ.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] The present invention adjusts the included angle between the carrier and the flow velocity in real time according to the flow velocity output by the analysis unit, thereby optimizing the accuracy and range;

[0023] By using the combination of the judgment unit, the controller and the drive unit, the automatic adjustment of the angle (i.e., the included angle between the carrier and the flow velocity direction) is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Referring to the accompanying drawings, the disclosure of the present invention will become more understandable. It is easy for those skilled in the art to understand that these drawings are only used to illustrate the technical solutions of the present invention and are not intended to limit the protection scope of the present invention. In the drawings:

[0025] Figure 1 is a schematic structural diagram of an ultrasonic flow velocity measurement device according to an embodiment of the present invention;

[0026] Figure 2 is a partial structural schematic diagram of an ultrasonic flow velocity measurement device according to an embodiment of the present invention. Detailed Implementation Modes

[0027] Figure 1 - Figure 2 The following description and explanations describe alternative specific implementation modes of the present invention to teach those skilled in the art how to implement and reproduce the present invention. To explain the technical solutions of the present invention, some conventional aspects have been simplified or omitted. Those skilled in the art should understand that variations or substitutions derived from these specific implementation modes will fall within the scope of the present invention. Those skilled in the art should understand that the following features can be combined in various ways to form multiple variations of the present invention. Thus, the present invention is not limited to the following alternative specific implementation modes, but is only defined by the claims and their equivalents.

[0028] Example 1.

[0029] Figure 1 A structural schematic diagram of the ultrasonic flow velocity measuring device according to an embodiment of the present invention is given, as Figure 1 shown, the ultrasonic flow velocity measuring device includes:

[0030] An analysis unit, a first transducer 21, a second transducer 22, and a carrier 11, and the first transducer 21 and the second transducer 22 are respectively arranged on the carrier 11. These components are all prior arts in the art.

[0031] A driving unit, the driving unit is used to drive the carrier 11 to rotate, and the rotation angle θ satisfies:

[0032] θ = arccos[(cosθ0) / k] - θ0, k ≥ cosθ0.

[0033] θ0 is the included angle between the initial position of the carrier 11 in the measurement environment and the flow velocity, and k is the ratio of the range corresponding to the adjusted position of the carrier 11 to the range corresponding to the initial position; if the angle θ is positive, the included angle between the carrier 11 and the flow velocity becomes larger, and if the angle θ is negative, the included angle between the carrier 11 and the flow velocity becomes smaller.

[0034] In order to automatically adjust the included angle between the carrier 11 and the flow velocity to optimize the accuracy and range, further, the ultrasonic flow velocity measuring device further includes:

[0035] A judgment unit, the judgment unit is used to judge whether the range corresponding to the current position of the carrier 11 meets the flow velocity requirement output by the analysis unit.

[0036] If the result is negative, the judgment unit issues a position adjustment instruction for the carrier 11 to the controller.

[0037] A controller, the controller calculates the rotation angle θ of the carrier 11 according to the adjustment instruction and transmits it to the driving unit.

[0038] In order to scientifically obtain the rotation angle, further, if the flow rate output by the analysis unit is greater than the first threshold aD0, where 0 < a < 1, the result is negative, D0 is the range corresponding to the current position of the carrier 11, the ratio of the first threshold to the adjusted new range kD0 is b, and 0 < b < a, then k = a / b > 1.

[0039] If the flow rate output by the analysis unit is less than the second threshold cD0, where 0 < c < a, the result is negative, D0 is the range corresponding to the current position of the carrier 11, the ratio of the second threshold to the adjusted new range kD0 is d, and c < d < 1, then k = c / d < 1, and c / d ≥ cosθ0.

[0040] In order to improve the control accuracy of the rotation angle, further, as Figure 2 shown, the first gear 31 is fixed on the carrier 11 and rotates around the rotating shaft 41 under drive, and θ is the rotation angle of the first gear 31.

[0041] The drive unit includes a motor and a second gear. The motor drives the second gear, and the second gear meshes with the first gear 31.

[0042] The ultrasonic flow rate measurement method of the embodiment of the present invention, that is, the working method of the measurement device in this embodiment, includes the following steps:

[0043] (A1) Determine whether the range corresponding to the current position of the carrier 11 meets the flow rate requirement output by the analysis unit.

[0044] If the result is negative, the judgment unit sends a position adjustment instruction for the carrier 11 to the controller.

[0045] The carrier 11 is arranged in the measurement environment, and the first transducer 21 and the second transducer 22 are respectively arranged on the carrier 11.

[0046] (A2) The controller calculates the rotation angle θ of the carrier 11 according to the adjustment instruction and transmits it to the drive unit.

[0047] θ = arccos[(cosθ0) / k] - θ0, where k ≥ cosθ0.

[0048] θ0 is the included angle between the initial position of the carrier 11 in the measurement environment and the flow rate, and k is the ratio of the range corresponding to the adjusted position of the carrier 11 to the range corresponding to the initial position; if the angle θ is positive, the included angle between the carrier 11 and the flow rate becomes larger, and if the angle θ is negative, the included angle between the carrier 11 and the flow rate becomes smaller.

[0049] (A3) The drive unit drives the carrier 11 to rotate, and the rotation angle is θ.

[0050] Embodiment 2.

[0051] Application example of the ultrasonic flow velocity measuring device and method according to Embodiment 1 of the present invention in flue gas flow velocity monitoring.

[0052] In this application example, as Figure 1 shown, the carrier 11 adopts a rod-shaped structure and is inserted into the flue. The first transducer 21 and the second transducer 22 are arranged on the carrier 11. The first gear 31 is arranged on the carrier 11 and rotates around the rotating shaft 41 under drive. The included angle θ0 between the initial position of the carrier 11 and the flue gas flow velocity is 45 ° , as Figure 2 shown.

[0053] The driving unit includes a motor and a second gear. The motor drives the second gear, and the second gear meshes with the first gear 31. So that when the motor drives the second gear to rotate, the carrier 11 rotates around the rotating shaft 41. The rotation angle θˊ of the second gear = N1·θ / N2, where N1 and N2 are the numbers of teeth of the first gear 31 and the second gear respectively, and θ is the rotation angle of the first gear 31.

[0054] The ultrasonic flow velocity measuring method of the embodiment of the present invention, that is, the working method of the measuring device in this embodiment, includes the following steps:

[0055] (A1) The judging unit judges whether the range corresponding to the current position of the carrier 11 meets the flow velocity requirement output by the analyzing unit. The specific judging method is:

[0056] If the flow velocity output by the analyzing unit is greater than the first threshold, k>1, the result is no.

[0057] If the flow velocity output by the analyzing unit is less than the second threshold, k<1, the result is no; the second threshold is less than the first threshold.

[0058] If the result is no, the judging unit issues a position adjustment instruction for the carrier 11 to the controller.

[0059] For example, the current included angle θ0 is 45 ° , and the corresponding range D0 = 20m / s. When the flow velocity output by the analyzing unit exceeds the first threshold 0.8D0 = 16m / s, a = 0.8, the result is no, and it is necessary to adjust the angle between the carrier 11 and the flow velocity. It is required that the ratio of the first threshold to the adjusted new range kD0 is 0.6, b = 0.6, then k = 0.8 / 0.6 = 1.33>cos45 ° , and the new range kD0 = 26.6m / s.

[0060] The current included angle θ0 is 45 °, the corresponding range is D0 = 20 m / s. When the flow velocity output by the analysis unit exceeds the first threshold of 0.9D0 = 18 m / s, a = 0.9, the result is no, and the angle between the carrier 11 and the flow velocity needs to be adjusted. It is required that the ratio of the first threshold to the adjusted new range kD0 is 0.5, b = 0.5, then k = 0.9 / 0.5 = 1.8 > cos45 ° , the new range kD0 = 36 m / s.

[0061] For example, the current included angle θ0 is 45 ° , the corresponding range is D0 = 20 m / s. When observing for a long time, when the flow velocity output by the analysis unit is less than the second threshold of 0.4D0 = 8 m / s, c = 0.4, the result is no, and the angle between the carrier 11 and the flow velocity needs to be adjusted. It is required that the ratio of the second threshold to the adjusted new range kD0 is 0.5, d = 0.5, then 1 > k = 0.4 / 0.5 = 0.8 > cos45 ° , the new range kD0 = 16 m / s.

[0062] The current included angle θ0 is 45 ° , the corresponding range is D0 = 20 m / s. When observing for a long time, when the flow velocity output by the analysis unit is less than the second threshold of 0.3D0 = 6 m / s, c = 0.3, the result is no, and the angle between the carrier 11 and the flow velocity needs to be adjusted. It is required that the ratio of the second threshold to the adjusted new range kD0 is 0.4, d = 0.4, then 1 > k = 0.3 / 0.4 = 0.75 > cos45 ° , the new range kD0 = 15 m / s.

[0063] (A2) The controller calculates the rotation angle θ of the carrier 11 according to the adjustment instruction and transmits it to the drive unit.

[0064] θ = arccos[(cosθ0) / k] - θ0, k ≥ cosθ0.

[0065] θ0 is the included angle between the initial position of the carrier 11 in the measurement environment and the flow velocity, and k is the ratio of the range corresponding to the adjusted position of the carrier 11 to the range corresponding to the initial position; if the angle θ is positive, the included angle between the carrier 11 and the flow velocity becomes larger, and if the angle θ is negative, the included angle between the carrier 11 and the flow velocity becomes smaller.

[0066] For example, k = 1.33, and θ ≈ 13 is obtained ° , that is, the included angle between the carrier 11 and the flow velocity becomes larger by 13 ° .

[0067] k = 1.8, and θ ≈ 21.87 is obtained ° , that is, the included angle between the carrier 11 and the flow velocity becomes larger by 21.87 °

[0068] When k = 0.8, θ≈-17.1 is obtained. ° The included angle between the carrier 11 and the flow velocity decreases by 17.1. ° .

[0069] When k = 0.75, θ≈-25.51 is obtained. ° The included angle between the carrier 11 and the flow velocity decreases by 25.51. ° .

[0070] (A3) The driving unit drives the carrier 11 to rotate according to the rotation angle θ. Specifically, the motor drives the second gear to rotate, and the first gear 31 rotates accordingly, thereby driving the carrier 11 to rotate by an angle of θ.

[0071] The rotation angle θˊ of the second gear = N1·θ / N2, where N1 and N2 are the numbers of teeth of the first gear 31 and the second gear respectively.

Claims

1. An ultrasonic flow velocity measuring device, comprising an analysis unit, a first transducer, a second transducer and a carrier, wherein the first transducer and the second transducer are respectively arranged on the carrier; characterized in that, The ultrasonic flow velocity measuring device further includes: a driving unit for driving the carrier to rotate, and the rotation angle θ satisfies: θ = arccos[(cosθ0) / k] - θ0, where k ≥ cosθ0; θ0 is the angle between the initial position of the carrier in the measurement environment and the flow velocity, and k is the ratio of the range corresponding to the adjusted position of the carrier to the range corresponding to the initial position; if the angle θ is positive, the angle between the carrier and the flow velocity becomes larger, and if the angle θ is negative, the angle between the carrier and the flow velocity becomes smaller; a judging unit for judging whether the range corresponding to the current position of the carrier meets the flow velocity requirement output by the analyzing unit; if the result is negative, the judging unit issues a carrier position adjustment instruction to the controller; if the flow velocity output by the analyzing unit is greater than the first threshold aD0, where 0 < a < 1, and the result is negative, D0 is the range corresponding to the current position of the carrier, the ratio of the first threshold to the adjusted new range kD0 is b, and 0 < b < a, then k = a / b > 1; if the flow velocity output by the analyzing unit is less than the second threshold cD0, where 0 < c < a, and the result is negative, D0 is the range corresponding to the current position of the carrier; the ratio of the second threshold to the adjusted new range kD0 is d, and c < d < 1, then k = c / d < 1, and c / d ≥ cosθ0; a controller for calculating the rotation angle θ of the carrier according to the adjustment instruction and transmitting it to the driving unit.

2. The ultrasonic flow velocity measuring device according to claim 1, characterized in that, The first gear is fixed on the carrier and rotates around the rotating shaft under driving, and θ is the rotation angle of the first gear; The driving unit includes a motor and a second gear, the motor drives the second gear, and the second gear meshes with the first gear.

3. The ultrasonic flow velocity measuring device according to claim 2, characterized in that, The rotation angle θˊ of the second gear = N1·θ / N2, where N1 and N2 are the numbers of teeth of the first gear and the second gear respectively.

4. The ultrasonic flow velocity measuring device according to claim 1, characterized in that, θ0 = π / 4.

5. An ultrasonic flow velocity measuring method, comprising the following steps: (A1) Judging whether the range corresponding to the current position of the carrier meets the flow velocity requirement output by the analyzing unit; if the result is negative, the judging unit issues a carrier position adjustment instruction to the controller; The carrier is arranged in the measurement environment, and the first transducer and the second transducer are respectively arranged on the carrier; if the flow velocity output by the analyzing unit is greater than the first threshold aD0, where 0 < a < 1, and the result is negative, D0 is the range corresponding to the current position of the carrier, the ratio of the first threshold to the adjusted new range kD0 is b, and 0 < b < a, then k = a / b > 1; if the flow velocity output by the analyzing unit is less than the second threshold cD0, where 0 < c < a, and the result is negative, D0 is the range corresponding to the current position of the carrier, the ratio of the second threshold to the adjusted new range kD0 is d, and c < d < 1, then k = c / d < 1, and c / d ≥ cosθ0; (A2) The controller calculates the rotation angle θ of the carrier according to the adjustment instruction and transmits it to the driving unit; θ = arccos[(cosθ0) / k] - θ0, where k ≥ cosθ0; θ0 is the included angle between the initial position of the carrier in the measurement environment and the flow velocity, and k is the ratio of the range corresponding to the position of the adjusted carrier to the range corresponding to the initial position; if the angle θ is positive, the included angle between the carrier and the flow velocity becomes larger, and if the angle θ is negative, the included angle between the carrier and the flow velocity becomes smaller. (A3) The driving unit drives the carrier to rotate by an angle of θ.

6. The ultrasonic flow velocity measurement method according to claim 5, characterized in that, The first gear is fixed on the carrier and rotates around the rotating shaft under drive, and θ is the rotation angle of the first gear. The driving unit includes a motor and a second gear. The motor drives the second gear, and the second gear meshes with the first gear.

7. The ultrasonic flow velocity measurement method according to claim 6, characterized in that The rotation angle θˊ of the second gear = N1·θ / N2, where N1 and N2 are the numbers of teeth of the first gear and the second gear respectively.

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