Ultrasonic flow velocity measurement device and method

Abstract

The invention relates to gas flow rate measurement, in particular to an ultrasonic flow rate measurement device and method, the measurement device comprises an analysis unit, a first transducer, a second transducer and a bearing part, and the first transducer and the second transducer are respectively arranged on the bearing part; the driving unit is used for driving the bearing part to rotate, the rotating angle theta meets the condition that theta = arccos [(cos theta0) / k]-theta0, and k is larger than or equal to cos theta0; theta0 is the included angle between the initial position of the bearing part in the measurement environment and the flow velocity, and k is the ratio of the measuring range corresponding to the position of the adjusted bearing part to the measuring range corresponding to the initial position; if the angle theta is positive, the included angle between the bearing piece and the flow velocity becomes larger, and if the angle theta is negative, the included angle between the bearing piece and the flow velocity becomes smaller. The method has the advantages of accurate measurement and the like.

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 the 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 the 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 not be sufficient 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 lead to a large error in the measurement result.

[0005] As can be seen from the above, when the angle of the flue gas ultrasonic flow velocity meter product is fixed, the corresponding range and accuracy are correspondingly 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 through the following technical solutions: 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: a driving unit for driving the carrier to rotate, and the rotation angle θ satisfies: θ = arccos[(cosθ 0 ) / k] - θ 0 , k ≥ cosθ 0 ; θ 0 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.

[0008] 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: An ultrasonic flow velocity measurement method, comprising the following steps: (A1) Determine whether the range corresponding to the current carrier position meets the flow velocity requirement output by the analysis unit; If the result is negative, the determination 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; (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[(cosθ 0 ) / k] - θ 0 , k ≥ cosθ 0 ; θ 0 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; (A3) The driving unit drives the carrier to rotate, and the rotation angle is θ.

[0009] Compared with the prior art, the beneficial effects of the present invention are: 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; By using the combination of the determination unit, the controller and the driving 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

[0010] 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: Figure 1 is a schematic structural diagram of an ultrasonic flow velocity measurement device according to an embodiment of the present invention; Figure 2 is a partial structural schematic diagram of an ultrasonic flow velocity measurement device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] Figure 1 - Figure 2The following description and the following examples describe alternative specific embodiments of the present invention to teach those skilled in the art how to implement and reproduce the present invention. To explain the technical solution 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 embodiments 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 embodiments, but is only defined by the claims and their equivalents.

[0012] Example 1.

[0013] Figure 1 A schematic structural 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: 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 art in the art.

[0014] A driving unit, the driving unit is used to drive the carrier 11 to rotate, and the rotation angle θ satisfies: θ = arccos[(cosθ 0 ) / k] - θ 0 , k ≥ cosθ 0 .

[0015] θ 0 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.

[0016] 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: 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.

[0017] If the result is negative, the judgment unit issues a position adjustment instruction for the carrier 11 to the controller.

[0018] 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.

[0019] In order to scientifically obtain the rotation angle, further, if the flow velocity output by the analysis unit is greater than the first threshold aD 0, 0 < a < 1, the result is no, D 0 is the range corresponding to the current position of the carrier 11, the first threshold value and the adjusted new range kD 0 The ratio of is b, and 0 < b < a, then k = a / b > 1.

[0020] If the flow rate output by the analysis unit is less than the second threshold value cD 0 , 0 < c < a, the result is no, D 0 is the range corresponding to the current position of the carrier 11, the second threshold value and the adjusted new range kD 0 The ratio of is d, and c < d < 1, then k = c / d < 1, and c / d ≥ cosθ 0 .

[0021] 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.

[0022] 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.

[0023] 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: (A1) Judge whether the range corresponding to the current position of the carrier 11 meets the flow rate requirement output by the analysis unit.

[0024] If the result is no, the judgment unit sends a position adjustment instruction for the carrier 11 to the controller.

[0025] 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.

[0026] (A2) The controller calculates the rotation angle θ of the carrier 11 according to the adjustment instruction and transmits it to the drive unit.

[0027] θ = arccos[(cosθ 0 ) / k] - θ 0 , k ≥ cosθ 0 .

[0028] θ 0 is the included angle between the initial position of the carrier 11 in the measurement environment and the flow rate, 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.

[0029] The driving unit (A3) drives the carrier 11 to rotate by an angle of θ.

[0030] Embodiment 2.

[0031] An 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.

[0032] 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 driving. The included angle θ between the initial position of the carrier 11 and the flue gas flow velocity 0 is 45 ° , as Figure 2 shown.

[0033] 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. 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 = N 1 ·θ / N 2 , where N 1 , N 2 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.

[0034] 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: The judging unit (A1) 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 as follows: If the flow velocity output by the analyzing unit is greater than the first threshold, k > 1, the result is no.

[0035] 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.

[0036] If the result is no, the judging unit sends a position adjustment instruction of the carrier 11 to the controller.

[0037] For example, the current included angle θ 0 is 45 ° , and the corresponding range D 0 = 20 m / s. When the flow velocity output by the analyzing unit exceeds the first threshold 0.8D 0 = 16 m / 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 first threshold and the adjusted new range kD 0The ratio is 0.6, b = 0.6, then k = 0.8 / 0.6 = 1.33 > cos45 ° , the new range kD 0 = 26.6 m / s.

[0038] The current included angle θ 0 is 45 ° , corresponding to the range D 0 = 20 m / s. When the flow velocity output by the analysis unit exceeds the first threshold 0.9D 0 = 18 m / s, a = 0.9, the result is no. 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 kD 0 is 0.5, b = 0.5, then k = 0.9 / 0.5 = 1.8 > cos45 ° , the new range kD 0 = 36 m / s.

[0039] For example, the current included angle θ 0 is 45 ° , corresponding to the range D 0 = 20 m / s. When observing for a long time, when the flow velocity output by the analysis unit is less than the second threshold 0.4D 0 = 8 m / s, c = 0.4, the result is no. It is necessary to adjust the angle between the carrier 11 and the flow velocity. It is required that the ratio of the second threshold to the adjusted new range kD 0 is 0.5, d = 0.5, then 1 > k = 0.4 / 0.5 = 0.8 > cos45 ° , the new range kD 0 = 16 m / s.

[0040] The current included angle θ 0 is 45 ° , corresponding to the range D 0 = 20 m / s. When observing for a long time, when the flow velocity output by the analysis unit is less than the second threshold 0.3D 0 = 6 m / s, c = 0.3, the result is no. It is necessary to adjust the angle between the carrier 11 and the flow velocity. It is required that the ratio of the second threshold to the adjusted new range kD 0 is 0.4, d = 0.4, then 1 > k = 0.3 / 0.4 = 0.75 > cos45 ° , the new range kD 0 = 15 m / s.

[0041] (A2) The controller calculates the rotation angle θ of the carrier 11 according to the adjustment instruction and transmits it to the drive unit.

[0042] θ = arccos[(cosθ 0 ) / k] - θ 0, k ≥ cosθ 0 .

[0043] θ 0 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.

[0044] For example, when k = 1.33, θ ≈ 13 ° , that is, the included angle between the carrier 11 and the flow velocity becomes larger by 13 ° .

[0045] When k = 1.8, θ ≈ 21.87 ° , that is, the included angle between the carrier 11 and the flow velocity becomes larger by 21.87 ° When k = 0.8, θ ≈ -17.1 ° , the included angle between the carrier 11 and the flow velocity becomes smaller by 17.1 ° .

[0046] When k = 0.75, θ ≈ -25.51 ° , the included angle between the carrier 11 and the flow velocity becomes smaller by 25.51 ° .

[0047] (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.

[0048] The rotation angle θˊ of the second gear = N 1 ·θ / N 2 , N 1 , N 2 are the number 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 also includes: A driving unit, the driving unit is used to drive the bearing to rotate, and the rotation angle θ satisfies: θ=arccos[(cosθ0) / k]-θ0, k≥cosθ0; θ0 is the angle between the initial position of the carrier in the measuring 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 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.

2. The ultrasonic flow velocity measuring device according to claim 1, characterized in that: The supersonic flow velocity measuring device also includes: A judging unit, the judging unit being used to judge whether the measuring range corresponding to the current position of the carrier meets the flow rate requirement output by the analyzing unit; If the result is no, the judgment unit sends a carrier position adjustment instruction to the controller; A controller is used to calculate the rotation angle θ of the carrier according to the adjustment instruction and transmit the calculation result to the driving unit.

3. The ultrasonic flow velocity measuring device according to claim 2, characterized in that: If the flow rate output by the analysis unit is greater than the first threshold aD0, 0<a<1, the result is no, 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 rate output by the analysis unit is less than the second threshold cD0, 0<c<a, the result is no, D0 is the range corresponding to the current carrier position, 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.

4. 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 the 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 is meshed with the first gear.

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

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

7. The ultrasonic flow velocity measurement method comprises the following steps: (A1) determining whether the measuring range corresponding to the current position of the carrier meets the flow rate requirement output by the analysis unit; If the result is no, the judgment unit sends a carrier position adjustment instruction to the controller; The carrier is arranged in a measuring environment, and the first transducer and the second transducer are arranged on the carrier respectively; (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, k≥cosθ0; θ0 is the angle between the initial position of the carrier in the measurement environment and the flow rate, and k is the ratio of the range corresponding to the position of the carrier after adjustment to the range corresponding to the initial position; if the angle θ is positive, the angle between the carrier and the flow rate becomes larger, and if the angle θ is negative, the angle between the carrier and the flow rate becomes smaller; (A3) The driving unit drives the supporting member to rotate, and the rotation angle is θ.

8. The ultrasonic flow velocity measurement method according to claim 7, characterized in that: If the flow rate output by the analysis unit is greater than the first threshold aD0, 0<a<1, the result is no, 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 rate output by the analysis unit is less than the second threshold cD0, 0<c<a, the result is no, D0 is the range corresponding to the current carrier position, 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.

9. The ultrasonic flow velocity measurement method according to claim 7, characterized in that: The first gear is fixed on the carrier and rotates around the rotating shaft under the 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 is meshed with the first gear.

10. The ultrasonic flow velocity measurement method according to claim 9, characterized in that: The rotation angle θˊ of the second gear is 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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