Calibration device and zeroing method for ultrasonic anemometer

Abstract

The present application provides a calibration device for zeroing an ultrasonic anemometer and a zeroing method thereof. The calibration device may include: a sealed cavity housing an ultrasonic anemometer; three groups of pitot tube anemometers, each group of pitot tube anemometers including a pitot tube, the total pressure measuring port of the pitot tube passing through the wall of the sealed cavity and penetrating into the sealed cavity, and the flow directions of the fluids in the total pressure side ports of the three groups of pitot tubes being perpendicular to each other; and a processor for calibrating the measured wind speed of the ultrasonic anemometer in the sealed cavity, the processor being connected to the ultrasonic anemometer. By utilizing the calibration device for zeroing an ultrasonic anemometer provided in the embodiment of the present application, the ultrasonic anemometer can be conveniently zeroed without disassembling the ultrasonic anemometer, thereby improving the calibration efficiency and reducing the cost.

Description

Technical Field

[0001] The present application relates to the technical field of ultrasonic anemometer calibration, and in particular to a calibration device and a zero calibration method for an ultrasonic anemometer. Background Art

[0002] The description in this section merely provides background information related to the disclosure of the present application and does not constitute prior art.

[0003] The working principle of ultrasonic anemometer is that when ultrasonic waves propagate in the air, the wind speed of the sound will change due to the influence of wind speed. Within a certain range, the transmitting transducer transmits a signal. In the case of tailwind and headwind, the two signals received by the receiving transducer have different time delays (relative to the time difference of the transmitted signal). This time difference is used to measure wind speed and direction.

[0004] During the signal processing, the ambient wind speed around the ultrasonic anemometer is 0 due to the influence of filter delay, transducer parameter differences, etc., but the wind speed actually measured by the ultrasonic anemometer is not 0, which causes the zero value of the ultrasonic anemometer to drift (that is, the value of the zero point changes). Zero drift will seriously affect the measurement accuracy of the ultrasonic anemometer, especially when measuring low wind speeds, the impact of zero drift is particularly serious, and it will even completely cause the ultrasonic anemometer to fail to work properly, so it is necessary to perform zero calibration on the ultrasonic anemometer.

[0005] However, most of the existing methods for zeroing ultrasonic anemometers are to create a windless environment in a wind tunnel for experiments before the ultrasonic anemometer leaves the factory, record the received signal of the ultrasonic anemometer and the wind speed and direction obtained at this moment, so as to achieve zeroing. However, due to changes in operating conditions such as temperature and humidity, or the influence of weather factors such as rain, fog, and dust, as well as factors such as scaling or wear of the transducer, the zero point value of the ultrasonic anemometer often drifts, and in this case, it is necessary to recalibrate its zero point. Recalibration generally requires the ultrasonic anemometer to be disassembled from the workplace, placed in a wind tunnel, and remeasured at zero wind speed to achieve zero point calibration of the ultrasonic anemometer.

[0006] Therefore, the zero point calibration method in the prior art requires disassembling the ultrasonic anemometer to complete the calibration, and its correction efficiency is low and the cost is high.

[0007] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present application and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because they are described in the background technology section of the present application. Summary of the invention

[0008] Based on the above-mentioned defects of the prior art, the embodiment of the present application provides a calibration device and a zeroing method for zeroing an ultrasonic anemometer, which can conveniently realize the zeroing of the ultrasonic anemometer without deliberately disassembling the ultrasonic anemometer.

[0009] In order to achieve the above objectives, this application provides the following technical solutions:

[0010] A calibration device for zeroing an ultrasonic anemometer, comprising:

[0011] A sealed chamber, the cover of which is arranged on the ultrasonic anemometer;

[0012] Three groups of Pitot tube anemometers, each group of the Pitot tube anemometers comprises a Pitot tube, the total pressure measuring port of the Pitot tube passes through the wall of the sealed cavity and penetrates into the sealed cavity, and the flow directions of the fluids in the total pressure side ports of the three groups of Pitot tubes are perpendicular to each other;

[0013] And, a processor for correcting the wind speed measured by the ultrasonic anemometer in the sealed cavity, wherein the processor is connected to the ultrasonic anemometer.

[0014] Preferably, the Pitot tube anemometer further comprises a differential pressure sensor for converting the total airflow pressure and the static airflow pressure measured by the Pitot tube into wind speed, and the differential pressure sensor is connected to the Pitot tube.

[0015] Preferably, the differential pressure sensor is arranged on the outer wall of the sealed cavity.

[0016] Preferably, three first through holes are arranged on the wall of the sealed cavity, and the Pitot tube penetrates into the sealed cavity through the first through holes.

[0017] Preferably, the sealed cavity includes a left half cavity, a right half cavity and a receiving hole, the receiving hole spans the left half cavity and the right half cavity, the facing end surfaces of the left half cavity and the right half cavity fit together to enclose the sealed cavity, the ultrasonic anemometer includes a base and a measuring arm arranged on the base, the base is received in the receiving hole, and the measuring arm is located in the sealed cavity.

[0018] Preferably, the calibration device also includes a temperature and humidity detector, which includes a temperature and humidity sensor and a first display connected to the temperature and humidity sensor. The temperature and humidity sensor is arranged in the sealed cavity and is used to measure the temperature and humidity in the sealed cavity. The first display is used to display the temperature and humidity measured by the temperature and humidity sensor.

[0019] Preferably, the calibration device further comprises a second display for displaying the wind speed after calibration of the ultrasonic anemometer, and the second display is connected to the ultrasonic anemometer.

[0020] A method for zeroing an ultrasonic anemometer using the above-mentioned calibration device comprises the following steps:

[0021] The three groups of Pitot tube anemometers are used to measure the wind speed in three mutually perpendicular directions in the sealed cavity;

[0022] When the wind speeds in the three mutually perpendicular directions measured by the Pitot tube anemometer are all less than a preset threshold, the processor corrects the wind speed measured by the ultrasonic anemometer at this time to zero.

[0023] Preferably, the method further comprises:

[0024] The second display displays the calibrated wind speed of the ultrasonic anemometer.

[0025] It can be seen that the calibration device and zeroing method provided by the present application provide a sealed chamber for the ultrasonic anemometer cover, use a Pitot tube anemometer to measure the wind speed in three mutually perpendicular directions in the sealed chamber, ensure that the ultrasonic anemometer is in a windless environment, and then use a processor to calibrate the wind speed of the ultrasonic anemometer to zero. There is no need to dismantle the ultrasonic anemometer and place it in a windless environment for zeroing, so the zeroing of the ultrasonic anemometer can be conveniently achieved, thereby improving calibration efficiency and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are for explanation purposes only and are not intended to limit the scope of the present application in any way. In addition, the shapes and proportional dimensions of the components in the drawings are only for illustration purposes and are used to help understand the present application. They do not specifically limit the shapes and proportional dimensions of the components of the present application. Under the guidance of the present application, those skilled in the art can select various possible shapes and proportional dimensions to implement the present application according to specific circumstances. In the drawings:

[0027] Figure 1 This is a schematic diagram of the structure of a calibration device for an ultrasonic anemometer according to an embodiment of the present application;

[0028] Figure 2 for Figure 1The exploded structural diagram of the calibration equipment and ultrasonic anemometer assembly shown;

[0029] Figure 3 The present invention is a flow chart of a method for zeroing an ultrasonic anemometer using the calibration device according to an embodiment of the present application.

[0030] In the attached picture:

[0031] 1: Sealed chamber 2: Ultrasonic anemometer

[0032] 3: Pitot tube 4: Differential pressure sensor

[0033] 5: Temperature and humidity sensor 6: First display

[0034] 7: Second display 101: First perforation

[0035] 102: Accommodating hole 103: Second through hole

[0036] 104: half cavity 301: outer tube

[0037] 302: Static pressure pipe. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0039] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may also be a centered element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be a centered element at the same time. The term "connection" as used herein may include electrical and / or mechanical physical connections. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0040] It should be emphasized that the term "and / or" used herein includes any and all combinations of one or more of the related listed items. The term "include / comprise" when used herein refers to the presence of a feature, a whole, a step or a component, but does not exclude the presence or addition of one or more other features, wholes, steps or components.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0042] An ultrasonic anemometer 2 comprises: a base, a control circuit board, four measuring arms and four ultrasonic transmitting / receiving probes; the four measuring arms are respectively connected to the base and are adjacent to each other at an angle of 90 degrees; the four ultrasonic transmitting / receiving probes are respectively installed at one end of the four measuring arms away from the base; among the four ultrasonic transmitting / receiving probes, two pairs of ultrasonic transmitting / receiving probes at an angle of 180 degrees relative to each other are in the same horizontal plane and have an equal vertical distance from the base.

[0043] like Figure 1 and Figure 2 As shown, the embodiment of the present application provides a calibration device for zeroing an ultrasonic anemometer, which is applicable to the above-mentioned ultrasonic anemometer 2, including:

[0044] A sealed chamber 1 housing the ultrasonic anemometer 2;

[0045] Three groups of Pitot tube anemometers (3, 4), each group of Pitot tube anemometers includes a Pitot tube 3, the total pressure measuring port of the Pitot tube 3 penetrates through the wall of the sealed chamber 1 and enters the sealed chamber 1, and the flow directions of the fluids in the total pressure side ports of the Pitot tubes 3 in the three groups of Pitot tube anemometers are perpendicular to each other, thereby realizing the measurement of wind speeds in three mutually perpendicular directions in the sealed chamber 1; and

[0046] A processor (not shown in the figure) for correcting the wind speed measured by the ultrasonic anemometer 2 in the sealed chamber 1 is connected to the ultrasonic anemometer 2. In this embodiment, the processor is a PC.

[0047] In this embodiment, the sealed cavity 1 can be any suitable spatial structure as required, for example, including but not limited to a cubic shape (such as Figure 1As shown), cylindrical, spherical, etc. Preferably, the sealed cavity 1 may include two relatively arranged half-cavities (i.e., a left half-cavity and a right half-cavity) 104, the left half-cavity and the right half-cavity are open toward each other's ends, and the facing end surfaces of the left half-cavity and the right half-cavity are fitted together to form a sealed cavity 1. In order to ensure the sealing performance of the sealed cavity 1, rubber or other materials may be used to seal the mutually fitted parts of the two half-cavities 104. At the same time, a receiving hole 102 is provided on the sealed cavity, and the receiving hole 102 is provided with two of the half-cavities 104. When the two half-cavities 104 are fitted together, the receiving hole 102 is a complete hole. When the sealed cavity 1 is covered on the ultrasonic anemometer, the base is accommodated in the receiving hole 102, and the measuring arm is located in the sealed cavity 1. The sealed chamber is provided in a detachable form. When the ultrasonic anemometer is at the work station, the sealed chamber 1 is disassembled into the two half chambers 104 and then enclosed. After the zero calibration is completed, the sealed chamber is disassembled into the two half chambers 104 and removed. This method can avoid disassembling the ultrasonic anemometer from the work station.

[0048] The wall of the sealed cavity 1 is further provided with three first through holes 101 for the Pitot tube 3 to pass through. Furthermore, the three first through holes 101 are arranged along three mutually perpendicular directions (eg, x, y and z directions).

[0049] Each set of Pitot tube anemometers (3, 4) may further include a differential pressure sensor 4 connected to the Pitot tube 3. The three Pitot tubes 3 may respectively penetrate into the sealed cavity 1 through three first through-holes 101 provided on the wall of the sealed cavity 1, and are respectively used to measure the total airflow pressure and the static airflow pressure in three mutually perpendicular directions in the sealed cavity 1. The three differential pressure sensors 4 may be provided on the outer wall of the sealed cavity 1, and are used to convert the total airflow pressure and the static airflow pressure in three mutually perpendicular directions measured by the three Pitot tubes 3 into wind speed.

[0050] Each Pitot tube 3 may include: a main pipe with openings at both ends, which can be used to measure the total pressure of the airflow in the sealed chamber 1 and send the measured total pressure of the airflow to the corresponding differential pressure sensor 4; an outer pipe 301, which can be mounted outside the main pipe, forming a static pressure annulus between the main pipe and the outer pipe, and a static pressure hole connected to the static pressure annulus is provided on the wall of the outer pipe 301; and a static pressure pipe 302, which can be connected to the outer wall of the outer pipe 301, can be used to measure the static pressure of the airflow in the sealed chamber 1, and is connected to the static pressure annulus to send the measured static pressure of the airflow to the corresponding differential pressure sensor 4 through the static pressure annulus and the static pressure hole.

[0051] Each differential pressure sensor 4 can be connected to the corresponding main pipe and static pressure pipe, and can convert the total airflow pressure and airflow static pressure sent by the corresponding main pipe and static pressure pipe 302 into wind speed, and send the converted wind speed to the processor. Specifically, the differential pressure sensor 4 can calculate the pressure difference between the total airflow pressure and the airflow static pressure, and then the wind speed can be calculated by using the pressure difference and according to the Bernoulli principle. For the specific calculation method, reference can be made to the prior art, which will not be repeated here. The wind speed output by the three differential pressure sensors 4 is the wind speed in three mutually perpendicular directions in the sealed chamber 1.

[0052] The processor can determine whether the ultrasonic anemometer 2 is in a windless environment based on the wind speeds sent by the three pressure difference sensors 4, and when it is determined that the ultrasonic anemometer 2 is in a windless environment, the wind speed measured by the ultrasonic anemometer 2 at this time is corrected to zero. Specifically, the processor can compare the wind speeds sent by the three pressure difference sensors 4 with a preset threshold value (for example, 0.01Pa), and when it is compared that the wind speeds sent by the three pressure difference sensors 4 are all less than the preset threshold value, it is determined that the ultrasonic anemometer 2 is in a windless environment, and then the wind speed measured by the ultrasonic anemometer 2 at this time is corrected to zero.

[0053] From the above description, it can be seen that the calibration device provided in the present application covers a sealed chamber 1 on an ultrasonic anemometer 2 located on a work station, and uses three groups of Pitot tube anemometers including three Pitot tubes 3 and three pressure difference sensors 4 to measure the wind speeds in three mutually perpendicular directions in the sealed chamber 1, thereby creating a windless environment for the ultrasonic anemometer 2, and uses a processor to calibrate the wind speed measured by the ultrasonic anemometer 2 to zero when the wind speeds in three mutually perpendicular directions measured by the three groups of Pitot tube anemometers are all less than a preset threshold value. The ultrasonic anemometer 2 can be easily calibrated to zero without disassembling the ultrasonic anemometer 2, thereby achieving the purpose of improving calibration efficiency and reducing costs.

[0054] In another embodiment of the present application, see Figure 2 , the calibration device may further include a temperature and humidity detector, which may include a temperature and humidity sensor 5 and a first display 6 connected to the temperature and humidity sensor 5. The temperature and humidity sensor 5 may be disposed in the sealed cavity 1, and specifically, its probe may enter therein through a second perforation 103 disposed on the wall of the sealed cavity 1. The temperature and humidity sensor 5 may be used to measure the temperature and humidity around the ultrasonic anemometer 2; the first display 6 may be used to display the temperature and humidity measured by the temperature and humidity sensor 5. By providing the temperature and humidity sensor 5 and the first display 6, the temperature and humidity around the ultrasonic anemometer 2 may be monitored in real time to avoid zero drift of the ultrasonic anemometer 2 caused by temperature and humidity.

[0055] In another embodiment of the present application, see Figure 2The calibration device may further include a second display 7, which may be connected to the ultrasonic anemometer 2 and fixed to the outer wall of the sealed chamber 1. The second display 7 may be used to display the real-time wind speed of the ultrasonic anemometer 2, including the wind speed after calibration. The embodiment of the present application also provides a method for zeroing the ultrasonic anemometer using the calibration device, such as Figure 3 The method may include the following steps:

[0056] Step S1: using three groups of Pitot tube anemometers to measure the wind speed in three mutually perpendicular directions in the sealed chamber 1 .

[0057] In actual operation, three groups of Pitot tube anemometers can be used to measure the wind speed in three mutually perpendicular directions in the sealed cavity 1. Specifically, the three Pitot tubes 3 in the Pitot tube anemometer can measure the total airflow pressure and static pressure in three mutually perpendicular directions in the sealed cavity 1, and send the measured total airflow pressure and static pressure to the three differential pressure sensors 4. The three differential pressure sensors 4 can calculate the pressure difference between the total airflow pressure measured by the Pitot tube 3 and the static pressure of the airflow, and then use the pressure difference and Bernoulli's principle to calculate the wind speed in three mutually perpendicular directions in the sealed cavity.

[0058] Step S2: When the wind speeds in three mutually perpendicular directions measured by the Pitot tube anemometer are all less than a preset threshold, the processor corrects the wind speed measured by the ultrasonic anemometer 2 at this time to zero.

[0059] The processor can judge whether the ultrasonic anemometer is in a windless environment by comparing the wind speeds sent by the three groups of pitot tube anemometers with a preset threshold value, and when it is judged that the ultrasonic anemometer 2 is in a windless environment, the wind speed measured by the ultrasonic anemometer 2 at this time is corrected to zero. Specifically, the processor can compare the wind speeds sent by the three differential pressure sensors 4 with a preset threshold value (for example, 0.01Pa), and when it is compared that the wind speeds sent by the three differential pressure sensors are all less than the preset threshold value, it is judged that the ultrasonic anemometer 2 is in a windless environment, and then the wind speed measured by the ultrasonic anemometer 2 at this time is corrected to zero.

[0060] From the above description, it can be seen that the zeroing method provided in the present application measures the wind speeds in three mutually perpendicular directions in the sealed chamber 1 by means of three groups of Pitot tube anemometers. When the wind speeds in three mutually perpendicular directions measured by the three groups of Pitot tube anemometers are all less than a preset threshold value, the processor corrects the wind speed measured by the ultrasonic anemometer 2 at this time to zero, thereby realizing the zeroing of the ultrasonic anemometer 2 in a windless environment. This can make the zeroing operation of the ultrasonic anemometer simple and practical, and very convenient and fast, with low cost.

[0061] In another embodiment of the present application, the method may further include:

[0062] Step S3: The second display 7 displays the calibrated wind speed of the ultrasonic anemometer 2 .

[0063] After the processor calibrates the wind speed measured by the ultrasonic anemometer 2 to zero, the second display 7 can display the calibrated wind speed of the ultrasonic anemometer 2, so as to determine whether the ultrasonic anemometer 2 is accurately calibrated, which is helpful to ensure the accuracy of zero calibration.

[0064] It should be noted that, in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and to distinguish similar objects. There is no order of precedence between the two, and they cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0065] The devices, apparatuses or components described in the above embodiments may be implemented by a chip or entity, or by a product having a certain function. For the convenience of description, the above devices and apparatuses are described separately by function into various components. Of course, when implementing the present application, the functions of each component may be implemented in the same or multiple chips.

[0066] It should be noted that although the present application provides method operation steps as described in the above embodiments or flow charts, more or fewer operation steps may be included in the method based on routine or no creative labor. In the steps that do not logically have a necessary causal relationship, the execution order of these steps is not limited to the execution order provided in the embodiments of the present application.

[0067] Features described and / or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.

[0068] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the method embodiment, since it is basically similar to the device embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the device embodiment.

[0069] It should be understood that the above description is for illustration and not for limitation. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but rather with reference to the foregoing claims and the full scope of equivalents to which such claims are entitled. For the purpose of comprehensiveness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended to be a waiver of such subject matter, nor should it be considered that the applicant has not considered such subject matter to be part of the disclosed inventive subject matter.

Claims

1. A calibration device for zeroing an ultrasonic anemometer, characterized in that: include: Sealed cavity; Three groups of Pitot tube anemometers, each group of the Pitot tube anemometers includes a Pitot tube, three first through-holes are arranged on the wall of the sealed cavity, the total pressure measuring port of the Pitot tube penetrates into the sealed cavity through the three first through-holes, and the flow directions of the fluids in the total pressure side ports of the three groups of Pitot tubes are perpendicular to each other; A processor, wherein the processor is connected to an ultrasonic anemometer; And, a second display is used to display the wind speed after correction by the ultrasonic anemometer, and the second display is connected to the ultrasonic anemometer.

2. The calibration device according to claim 1, characterized in that The Pitot tube anemometer also includes a pressure difference sensor for converting the total airflow pressure and the airflow static pressure measured by the Pitot tube into wind speed, and the pressure difference sensor is connected to the Pitot tube.

3. The calibration device according to claim 2, characterized in that The differential pressure sensor is arranged on the outer wall of the sealed cavity.

4. The calibration device according to claim 1, characterized in that The sealed cavity includes a left half cavity, a right half cavity and a receiving hole, the receiving hole spans the left half cavity and the right half cavity, the facing end surfaces of the left half cavity and the right half cavity fit together to enclose the sealed cavity, the ultrasonic anemometer includes a base and a measuring arm arranged on the base, the base is received in the receiving hole, and the measuring arm is located in the sealed cavity.

5. The calibration device according to claim 1, characterized in that The calibration device also includes a temperature and humidity detector, which includes a temperature and humidity sensor and a first display connected to the temperature and humidity sensor. The temperature and humidity sensor is arranged in the sealed cavity and is used to measure the temperature and humidity in the sealed cavity. The first display is used to display the temperature and humidity measured by the temperature and humidity sensor.

6. A method for zeroing an ultrasonic anemometer using the calibration device according to any one of claims 1 to 5, characterized in that: The steps include: The three groups of Pitot tube anemometers are used to measure the wind speed in three mutually perpendicular directions in the sealed cavity; When the wind speeds in the three mutually perpendicular directions measured by the Pitot tube anemometer are all less than a preset threshold, the processor corrects the wind speed measured by the ultrasonic anemometer at this time to zero.

7. The method according to claim 6, characterized in that The calibration device further comprises a second display for displaying the wind speed after calibration of the ultrasonic anemometer, wherein the second display is connected to the ultrasonic anemometer, and the wind speed after calibration of the ultrasonic anemometer is displayed by the second display.

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