A calibration method for voltage-angle relationship of a wind tunnel test air speed tube with a wind vane

Abstract

A kind of calibration method of voltage-angle relationship of wind tunnel test with wind vane air speed tube based on gravity belongs to wind tunnel test field.The present application is to solve the problem that current wind vane air speed tube is highly dependent on special calibration device, and the installation effect of special calibration device affects the accuracy of calibration results during calibration process. The present application respectively uses wind tunnel bending knife and laser level to complete the voltage-angle calibration of pitch channel of wind vane air speed tube and the voltage-angle calibration of yaw channel of wind vane air speed tube. The method of the present application can greatly improve the standardization degree of voltage-angle relationship calibration work, and better support the calibration work of voltage-angle relationship of wind vane air speed tube.

Description

Technical Field

[0001] This invention belongs to the field of wind tunnel testing, specifically relating to a calibration method for the voltage-angle relationship of a wind tunnel tube with a wind vane used in gravity-based wind tunnel testing. Background Technology

[0002] The pitot tube with wind indicator is a key measuring device for the attitude and speed of an aircraft. Its characteristics need to be calibrated in detail in the wind tunnel during the design phase of the aircraft.

[0003] Currently, with the increase in wind tunnel diameter, the size of wind tunnel test models with wind vanes is also getting larger, and it is now possible to retain the wind vane structure and create more realistic models. Unlike traditional wind tunnel force and pressure measurement tests, wind vane-equipped pitot tubes must first calibrate the voltage-angle relationship under windless conditions, and then use this relationship to conduct actual measurements under windy conditions to obtain the true output of the wind vane-equipped pitot tube under the aerodynamic layout conditions of the aircraft.

[0004] The existing voltage-angle calibration process for pitot tubes with weather vanes under windless conditions has two problems: (1) The structures of pitot tubes with weather vanes used by different types of aircraft vary greatly, and a dedicated calibration device is required for each pitot tube with weather vanes. (2) The installation and positioning effect of the dedicated calibration device will significantly affect the accuracy of the voltage-angle relationship of the calibrated pitot tube with weather vanes. (3) The standardization of the calibration work is low.

[0005] Therefore, it is necessary to establish a calibration method that can be used without relying on a dedicated calibration device for the voltage-angle calibration of pitot tubes with wind indicators, so as to better support the calibration of the voltage-angle relationship of pitot tubes with wind indicators. Summary of the Invention

[0006] This invention provides a calibration method for the voltage-angle relationship of a wind tunnel penetrating tube, which solves the problem that current wind tunnel penetrating tubes rely heavily on dedicated calibration devices, and that the installation effect of the dedicated calibration device affects the accuracy of the calibration results. This invention better supports the calibration of the voltage-angle relationship of wind tunnel penetrating tubes.

[0007] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0008] A method for calibrating the voltage-angle relationship of a wind tunnel anemometer pitot tube includes the following steps:

[0009] S1. Use wind tunnel bevels and laser level to complete the voltage-angle calibration of the pitot tube pitch channel with wind vane;

[0010] S1.1 In the wind tunnel test section, the installation of the support, the main body of the model, and the pitot tube with the angle of attack measuring indicator is completed in sequence;

[0011] S1.2 Connect the airspeed tube with the measuring angle of attack airspeed indicator to the wind tunnel test data acquisition system to ensure that the acquisition system correctly acquires the voltage signal when the measuring angle of attack airspeed indicator rotates.

[0012] S1.3 Using the pitch and roll mechanism of the wind tunnel bevel, the model attitude is adjusted to a pitch angle of 0° and a roll angle of 0° relative to the ground;

[0013] S1.4 Using the pitch mechanism of the wind tunnel bevel and a laser level, the voltage-angle correspondence of the negative angle sequence 1 of the pitot tube with angle of attack measurement is completed. Calibration;

[0014] S1.4.1 Using the pitch mechanism of the wind tunnel bevel, the bevel mechanism is adjusted to the negative limit state of the pitch angle. ;

[0015] S1.4.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung at the head of the structure with the anemometer for measuring angle of attack. Under the action of the weight's gravity, the anemometer for measuring angle of attack hangs down naturally in the negative direction.

[0016] S1.4.3 Fine-tune the orientation of the pitot tube of the anemometer with measuring angle of attack. Using a laser level, ensure that the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the pitot tube corresponding to the anemometer with measuring angle of attack is... ;

[0017] S1.4.4 Using the wind tunnel bevel pitch mechanism, starting from the position of S1.4.3, the system moves at 1° intervals until the wind tunnel bevel reaches its positive pitch limit. There are a total of n pause points, and the output voltage of the pipe with the airspeed indicator measuring the angle of attack is recorded under each pause point condition. The calibration angle of the pitot tube channel with measuring angle of attack corresponding to each pause point is: ;

[0018] S1.4.5 Using the data obtained in S1.4.4, establish... The correspondence is as follows:

[0019]

[0020] S1.5 Using the pitch mechanism of the wind tunnel bevel and a laser level, the voltage angle correspondence of the pitot tube positive angle sequence 2 with the angle of attack measurement wind vane is completed. Calibration;

[0021] S1.5.1 Using the pitch mechanism of the wind tunnel bevel, the model's attitude angle is adjusted to the positive limit state of the pitch angle. ;

[0022] S1.5.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung at the tail of the structure with the anemometer for measuring angle of attack. Under the action of the weight's gravity, the anemometer for measuring angle of attack hangs down naturally in the positive direction.

[0023] S1.5.3 Fine-tune the orientation of the pitot tube with the measuring angle of attack. Using a laser level, ensure that the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the pitot tube with the measuring angle of attack is... ;

[0024] S1.5.4 Using the wind tunnel bend mechanism, starting from the position of S3.3, run at 1° intervals until the negative limit of the wind tunnel bend's pitch angle. There are a total of n pause points, and the output voltage of the pitot tube channel with the angle of attack measurement is recorded under each pause point condition. The calibration angle of the pitot tube channel with measuring angle of attack corresponding to each pause point is: ;

[0025] S1.5.5 Using the data obtained in S1.5.4, establish... The correspondence is as follows:

[0026]

[0027] S1.6 Using the correspondence established in S1.4.5 and S1.5.5, the voltage-angle relationship of the pitot tube with measuring angle of attack is obtained by linear fitting of all voltage-angle data. .

[0028]

[0029] Using the corresponding data in the table, and applying the principle of univariate linear regression, fit a linear equation. The slope ,intercept In the above formula, , .

[0030] S2. Use wind tunnel bevels and laser level to complete the voltage-angle calibration of the yaw channel with wind vane and pitot tube;

[0031] S2.1 In the wind tunnel test section, the installation of the support, the main body of the model, and the anemometer pitot tube with the sideslip angle measurement is completed in sequence;

[0032] S2.2 Connect the airspeed tube channel with the measuring sideslip angle anemometer to the wind tunnel test data acquisition system to ensure that the acquisition system correctly acquires the voltage signal when the measuring sideslip angle anemometer rotates.

[0033] S2.3 Using the pitch and roll mechanism of the wind tunnel bevel, the model attitude is adjusted to a pitch angle of 0° and a roll angle of 90° relative to the ground;

[0034] S2.4 Using the pitch mechanism of the wind tunnel bevel and a laser level, the voltage angle correspondence of the negative angle sequence 3 of the anemometer pitot tube with sideslip angle measurement is completed. Calibration;

[0035] S2.4.1 Using the pitch mechanism of the wind tunnel bevel, adjust the bevel mechanism to the negative limit state of the pitch angle. ;

[0036] S2.4.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung on the head of the anemometer pitot tube structure with measuring side slip angle. Under the action of the weight's gravity, the anemometer pitot tube with measuring side slip angle hangs down naturally in the negative direction.

[0037] S2.4.3 Fine-tune the orientation of the pitot tube with measuring sideslip angle. Using a laser level, ensure the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the pitot tube with measuring sideslip angle is... ;

[0038] S2.4.4 Using the wind tunnel bevel pitch mechanism, starting from the position of S2.4.3, the system moves at 1° intervals until the wind tunnel bevel reaches its positive pitch limit. There are a total of n pause points, and the output voltage of the anemometer airspeed pipeline with sideslip angle measurement is recorded under each pause point condition. The calibration angle of the airspeed tube channel with measuring sideslip angle corresponding to each pause point is: ;

[0039] S2.4.5 Using the data obtained in S2.4.4, establish... The correspondence is as follows:

[0040]

[0041] S2.5 Using the pitch mechanism of the wind tunnel bevel and a laser level, the voltage angle correspondence of the pitot tube positive angle sequence 4 with sideslip angle measurement is completed. Calibration;

[0042] S2.5.1 Using the pitch mechanism of the wind tunnel bevel, the model's attitude angle is adjusted to the positive limit state of the pitch angle. ;

[0043] S2.5.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung at the tail of the anemometer pitot tube structure with measuring side slip angle. Under the action of the weight's gravity, the anemometer pitot tube with measuring side slip angle hangs down naturally in the positive direction.

[0044] S2.5.3 Fine-tune the orientation of the anemometer pitot tube (sideslip angle). Using a laser level, ensure the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the anemometer pitot tube with the sideslip angle measurement function is... ;

[0045] S2.5.4 Using the wind tunnel bend mechanism, starting from the position of S2.5.3, run at 1° intervals until the negative limit of the wind tunnel bend's pitch angle. There are a total of n pause points, and the output voltage of the anemometer pitot tube channel with sideslip angle measurement is recorded under each pause point condition. The calibration angle of the airspeed tube channel with measuring sideslip angle corresponding to each pause point is: ;

[0046] S2.5.5 uses the data obtained from S2.5.4 to establish... The correspondence is as follows:

[0047]

[0048] S2.6 Using the correspondence established in S2.4.5 and S2.5.5, the voltage-angle relationship of the anemometer pitot tube with measured sideslip angle is obtained by linear fitting. .

[0049]

[0050] Using the corresponding data in the table, and applying the principle of univariate linear regression, fit a linear equation. The slope ,intercept In the above formula, , .

[0051] The beneficial effects of this invention are as follows:

[0052] 1. The method of this invention eliminates the need for designing and fabricating a dedicated calibration device for the pitot tube with an anemometer, reducing design and fabrication costs; it avoids the impact of installation errors of the dedicated calibration device on the calibration results, improving the accuracy of the calibration work; it only requires the existing angle mechanism of the wind tunnel, data acquisition system, laser level, thin copper wire, and weights to complete the voltage-angle relationship calibration of the pitot tube with anemometer under windless conditions, and the method has high versatility, stability, and standardization.

[0053] 2. The voltage-angle relationship of the pitot tube with wind vane obtained by the method of the present invention has good repeatability and operability, and can be applied to various wind tunnel tests of pitot tubes with wind vane, eliminating the dependence on calibration devices and greatly improving the standardization of calibration. Attached Figure Description

[0054] Figure 1 This is a flowchart of the method steps of the present invention;

[0055] Figure 2 This is a schematic diagram of the installation of a pitot tube with an angle-of-attack measuring indicator;

[0056] Figure 3 A schematic diagram illustrating the calibration process for the negative angle of the pitot tube of the anemometer for measuring the angle of attack;

[0057] Figure 4 A schematic diagram illustrating the calibration process for the positive angle of the pitot tube of an anemometer measuring the angle of attack;

[0058] Figure 5 This is a schematic diagram of the installation of a pitot tube with a sideslip angle measuring indicator;

[0059] Figure 6 A schematic diagram illustrating the calibration process for the negative angle of the airspeed tube of a wind vane for measuring the sideslip angle;

[0060] Figure 7 A schematic diagram illustrating the calibration process for the positive angle of the airspeed tube of a wind vane used to measure the sideslip angle;

[0061] In the diagram: 1-Wind tunnel bevel, 2-Laser level, 3-Support, 4-Main model, 5-Pneumatic tube with angle of attack measuring indicator, 6-Angle of attack measuring indicator, 7-Copper wire, 8-Weights, 9-Pneumatic tube with sideslip measuring indicator, 10-Sideslip measuring indicator. Detailed Implementation

[0062] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0063] Specific implementation method one: Combining Figures 1-7This embodiment describes a method for calibrating the voltage-angle relationship of a wind tunnel anemometer pitot tube. The method utilizes a wind tunnel bender mechanism and a laser level, wherein:

[0064] The wind tunnel bevel, or wind tunnel bevel structure, is capable of independently completing two degrees of freedom operation: pitch and roll.

[0065] The laser level is an opto-mechatronic instrument used to project horizontal, vertical, or cross-shaped laser reference lines.

[0066] The method specifically includes the following steps:

[0067] S1. Use wind tunnel bevel 1 and laser level 2 to complete the voltage-angle calibration of the pitot tube pitch channel with wind vane;

[0068] S1.1 In the wind tunnel test section, the installation of support 3, model body 4, and pitot tube with angle of attack measuring indicator 5 is completed in sequence;

[0069] S1.2 Connect the airspeed tube with measuring angle of attack to the wind tunnel test data acquisition system to ensure that the acquisition system correctly acquires the voltage signal when the airspeed tube with measuring angle of attack 6 rotates.

[0070] S1.3 Using the pitch and roll mechanism of the wind tunnel bevel 1, the model attitude is adjusted to a pitch angle of 0° and a roll angle of 0° relative to the ground;

[0071] S1.4 Using the pitch mechanism of the wind tunnel bevel and the laser level 2, the voltage-angle correspondence of the negative angle sequence 1 of the anemometer with angle of attack measurement is completed. Calibration;

[0072] S1.4.1 Using the pitch mechanism of the wind tunnel bevel, the bevel mechanism is adjusted to the negative limit state of the pitch angle. ;

[0073] S1.4.2 Using a thin copper wire 7 with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight 8 is suspended and stably hung at the head of the structure with the measuring angle of attack wind vane pitot tube. Under the action of the weight's gravity, the measuring angle of attack wind vane pitot tube hangs down naturally in the negative direction.

[0074] S1.4.3 Fine-tune the orientation of the pitot tube 5 with the measuring angle of attack. Using the laser level 2, ensure that the vertical optical path of the laser level 2 covers the entire copper wire 7. At this point, the calibrated angle of the pitot tube with the measuring angle of attack is... ;

[0075] S1.4.4 Using the wind tunnel bevel pitch mechanism, starting from the position of S1.4.3, the system moves at 1° intervals until the wind tunnel bevel reaches its positive pitch limit. There are a total of n pause points, and the output voltage of the pipe with the airspeed indicator measuring the angle of attack is recorded under each pause point condition. The calibration angle of the pitot tube channel with measuring angle of attack corresponding to each pause point is: ;

[0076] S1.4.5 Using the data obtained in S1.4.4, establish... The correspondence;

[0077] S1.5 Using the pitch mechanism of the wind tunnel bevel 1 and the laser level 2, the voltage angle correspondence of the pitot tube positive angle sequence 2 with the angle of attack measurement wind vane is completed. Calibration;

[0078] S1.5.1 Using the pitch mechanism of the wind tunnel bevel 1, the model's attitude angle is adjusted to the positive limit state of the pitch angle. ;

[0079] S1.5.2 Using a thin copper wire 7 with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight 8 is suspended and stably hung at the tail of the pitot tube structure with the angle of attack measuring wind vane. Under the gravity of the weight 8, the pitot tube 5 with the angle of attack measuring wind vane hangs down naturally in the positive direction.

[0080] S1.5.3 Fine-tune the orientation of the pitot tube 5 with the measuring angle of attack. Using the laser level 2, ensure that the vertical optical path of the laser level 2 covers the entire copper wire 7. At this point, the calibrated angle of the pitot tube with the measuring angle of attack is... ;

[0081] S1.5.4 Using the wind tunnel bend mechanism, starting from the position of S3.3, run at 1° intervals until the negative limit of the wind tunnel bend's pitch angle. There are a total of n pause points, and the output voltage of the pitot tube channel with the angle of attack measurement is recorded under each pause point condition. The calibration angle of the pitot tube channel with measuring angle of attack corresponding to each pause point is: ;

[0082] S1.5.5 Using the data obtained in S1.5.4, establish... The correspondence;

[0083] S1.6 Using the correspondence established in S1.4.5 and S1.5.5, the voltage-angle relationship of the pitot tube with measuring angle of attack is obtained by linear fitting of all voltage-angle data. .

[0084] S2. Use wind tunnel bevel 1 and laser level 2 to complete the voltage-angle calibration of the yaw channel with wind vane and pitot tube;

[0085] S2.1 In the wind tunnel test section, the installation of support 3, model body 4, and airspeed tube with measuring sideslip angle is completed in sequence;

[0086] S2.2 Connect the airspeed tube channel with measuring sideslip angle to the wind tunnel test data acquisition system to ensure that the acquisition system correctly acquires the voltage signal when the measuring sideslip angle airspeed tube 10 rotates;

[0087] S2.3 Using the pitch and roll mechanism of the wind tunnel bevel 1, the model attitude is adjusted to a pitch angle of 0° and a roll angle of 90° relative to the ground;

[0088] S2.4 Using the pitch mechanism of the wind tunnel bevel 1 and the laser level 2, the voltage angle correspondence of the negative angle sequence 3 of the anemometer pitot tube with sideslip angle measurement is completed. Calibration;

[0089] S2.4.1 Using the pitch mechanism of the wind tunnel bevel 1, adjust the bevel mechanism to the negative limit state of the pitch angle. ;

[0090] S2.4.2 Using a thin copper wire 7 with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight 8 is suspended and stably hung at the head of the anemometer pitot tube structure with measuring side slip angle. Under the action of the weight 8, the anemometer pitot tube 9 with measuring side slip angle hangs down naturally in the negative direction.

[0091] S2.4.3 Fine-tune the orientation of the pitot tube 9 with measuring sideslip angle. Using the laser level 2, ensure that the vertical optical path of the laser level 2 covers the entire copper wire 7. At this point, the calibrated angle of the pitot tube 9 with measuring sideslip angle is... ;

[0092] S2.4.4 Using the wind tunnel bevel pitch mechanism, starting from the position of S2.4.3, the system moves at 1° intervals until the wind tunnel bevel reaches its positive pitch limit. There are a total of n pause points, and the output voltage of the anemometer airspeed pipeline with sideslip angle measurement is recorded under each pause point condition. The calibration angle of the airspeed tube channel with measuring sideslip angle corresponding to each pause point is: ;

[0093] S2.4.5 Using the data obtained in S2.4.4, establish... The correspondence;

[0094] S2.5 Using the pitch mechanism of the wind tunnel bevel 1 and the laser level 2, the voltage angle correspondence of the anemometer pitot tube positive angle sequence 4 with sideslip angle measurement is completed. Calibration;

[0095] S2.5.1 Using the pitch mechanism of the wind tunnel bevel 1, the model's attitude angle is adjusted to the positive limit state of the pitch angle. ;

[0096] S2.5.2 Using a thin copper wire 7 with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight 8 is suspended and stably hung at the tail of the anemometer pitot tube structure 9 with measuring side slip angle. Under the gravity of the weight 8, the anemometer pitot tube 9 with measuring side slip angle hangs down naturally in the positive direction.

[0097] S2.5.3 Fine-tune the orientation of the anemometer pitot tube (sideslip angle). Using the laser level 2, ensure that the vertical optical path of the laser level 2 covers the entire copper wire 7. At this point, the calibrated angle of the anemometer pitot tube 9 with the sideslip angle measurement is... ;

[0098] S2.5.4 Using the wind tunnel bend mechanism, starting from the position of S2.5.3, run at 1° intervals until the negative limit of the wind tunnel bend's pitch angle. There are a total of n pause points, and the output voltage of the anemometer pitot tube channel with sideslip angle measurement is recorded under each pause point condition. The calibration angle of the airspeed tube channel with measuring sideslip angle corresponding to each pause point is: ;

[0099] S2.5.5 uses the data obtained from S2.5.4 to establish... The correspondence;

[0100] S2.6 Using the correspondence established in S2.4.5 and S2.5.5, the voltage-angle relationship of the anemometer pitot tube with measured sideslip angle is obtained by linear fitting. . Specific Implementation Method Two:

[0102] For a wind tunnel test of a pitot tube with a weather vane, voltage-angle calibration was performed under no-wind conditions following the steps described above, obtaining reliable voltage-angle calibration relationships for the pitch and yaw channels. The results of voltage-angle calibration using this method and the traditional method (using a dedicated calibration device) are shown in the table below. It can be seen that the repeatability error is relatively large when using the dedicated device; the voltage-angle relationship calibrated using this method shows a better-than-0.13% consistency deviation in K and a better-than-0.025% consistency deviation in b compared to the result calibrated using the dedicated device. Using this method to complete the pitch and yaw calibration of the pitot tube with a weather vane eliminates the need to install / remove any mechanical structures related to the model / calibration process, completely avoiding calibration errors caused by installation deviations of the dedicated calibration device.

[0103] .

[0104] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A calibration method for the voltage-angle relationship of a pitot tube with an anemometer used in gravity-based wind tunnel testing, characterized in that, Includes the following steps: S1. Using a wind tunnel bevel and laser level, perform voltage-angle calibration of the pitot tube pitch channel with wind vane. The specific steps are as follows: S1.1 In the wind tunnel test section, the installation of the support, the main body of the model, and the pitot tube with the angle of attack measuring indicator is completed in sequence; S1.2 Connect the airspeed tube with the measuring angle of attack airspeed indicator to the wind tunnel test data acquisition system to ensure that the acquisition system correctly acquires the voltage signal when the measuring angle of attack airspeed indicator rotates. S1.3 Using the pitch and roll mechanism of the wind tunnel bevel, the model attitude is adjusted to a pitch angle of 0° and a roll angle of 0° relative to the ground; S1.4 Using the pitch mechanism of the wind tunnel bevel and a laser level, the voltage-angle correspondence of the negative angle sequence 1 of the pitot tube with angle of attack measurement is completed. Calibration; S1.5 Using the pitch mechanism of the wind tunnel bevel and a laser level, the voltage angle correspondence of the pitot tube positive angle sequence 2 with the angle of attack measurement wind vane is completed. Calibration; S1.6 Using the correspondence established in S1.4.5 and S1.5.5, the voltage-angle relationship of the pitot tube with measuring angle of attack is obtained by linear fitting of all voltage-angle data. ; S2. Use wind tunnel bevels and laser level to complete the voltage-angle calibration of the yaw channel with wind vane and pitot tube; S2.1 In the wind tunnel test section, the installation of the support, the main body of the model, and the anemometer pitot tube with the sideslip angle measurement is completed in sequence; S2.2 Connect the airspeed tube channel with the measuring sideslip angle anemometer to the wind tunnel test data acquisition system to ensure that the acquisition system correctly acquires the voltage signal when the measuring sideslip angle anemometer rotates. S2.3 Using the pitch and roll mechanism of the wind tunnel bevel, the model attitude is adjusted to a pitch angle of 0° and a roll angle of 90° relative to the ground; S2.4 Using the pitch mechanism of the wind tunnel bevel and a laser level, the voltage angle correspondence of the negative angle sequence 3 of the anemometer pitot tube with sideslip angle measurement is completed. Calibration; S2.5 Using the pitch mechanism of the wind tunnel bevel and a laser level, the voltage angle correspondence of the pitot tube positive angle sequence 4 with sideslip angle measurement is completed. Calibration; S2.5.1 Using the pitch mechanism of the wind tunnel bevel, the model's attitude angle is adjusted to the positive limit state of the pitch angle. ; S2.5.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung at the tail of the anemometer pitot tube structure with measuring side slip angle. Under the action of the weight's gravity, the anemometer pitot tube with measuring side slip angle hangs down naturally in the positive direction. S2.5.3 Fine-tune the orientation of the anemometer pitot tube (sideslip angle). Using a laser level, ensure the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the anemometer pitot tube with the sideslip angle measurement function is... ; S2.5.4 Using the wind tunnel bend mechanism, starting from the position of S2.5.3, run at 1° intervals until the negative limit of the wind tunnel bend's pitch angle. There are a total of n pause points, and the output voltage of the anemometer pitot tube channel with sideslip angle measurement is recorded under each pause point condition. The calibration angle of the airspeed tube channel with measuring sideslip angle corresponding to each pause point is: ; S2.5.5 uses the data obtained from S2.5.4 to establish... The correspondence; S2.6 Using the correspondence established in S2.4.5 and S2.5.5, the voltage-angle relationship of the anemometer pitot tube with measured sideslip angle is obtained by linear fitting. .

2. The calibration method for voltage-angle relationship of pitot tube with an anemometer in a gravity-based wind tunnel test according to claim 1, characterized in that: In step S1.4, the calibration process for the voltage-angle correspondence of the negative angle sequence 1 of the wind tunnel bevel and the laser level is completed using the pitch mechanism of the wind tunnel bevel and the laser level: S1.4.1 Using the pitch mechanism of the wind tunnel bevel, the bevel mechanism is adjusted to the negative limit state of the pitch angle. ; S1.4.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung at the head of the structure with the anemometer for measuring angle of attack. Under the action of the weight's gravity, the anemometer for measuring angle of attack hangs down naturally in the negative direction. S1.4.3 Fine-tune the orientation of the pitot tube of the anemometer with measuring angle of attack. Using a laser level, ensure that the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the pitot tube corresponding to the anemometer with measuring angle of attack is... ; S1.4.4 Using the wind tunnel bevel pitch mechanism, starting from the position of S1.4.3, the system moves at 1° intervals until the wind tunnel bevel reaches its positive pitch limit. There are a total of n pause points, and the output voltage of the pipe with the airspeed indicator measuring the angle of attack is recorded under each pause point condition. The calibration angle of the pitot tube channel with measuring angle of attack corresponding to each pause point is: ; S1.4.5 Using the data obtained in S1.4.4, establish... The correspondence.

3. The calibration method for voltage-angle relationship of pitot tube with an anemometer in a gravity-based wind tunnel test according to claim 1, characterized in that: In step S1.5, the calibration process for the voltage-angle correspondence of the wind tunnel bevel and the laser level, using the pitch mechanism and laser level of the wind tunnel bevel, is as follows: S1.5.1 Using the pitch mechanism of the wind tunnel bevel, the model's attitude angle is adjusted to the positive limit state of the pitch angle. ; S1.5.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung at the tail of the structure with the anemometer for measuring angle of attack. Under the action of the weight's gravity, the anemometer for measuring angle of attack hangs down naturally in the positive direction. S1.5.3 Fine-tune the orientation of the pitot tube with the measuring angle of attack. Using a laser level, ensure that the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the pitot tube with the measuring angle of attack is... ; S1.5.4 Using the wind tunnel bend mechanism, starting from the position of S3.3, run at 1° intervals until the negative limit of the wind tunnel bend's pitch angle. There are a total of n pause points, and the output voltage of the pitot tube channel with the angle of attack measurement is recorded under each pause point condition. The calibration angle of the pitot tube channel with measuring angle of attack corresponding to each pause point is: ; S1.5.5 Using the data obtained in S1.5.4, establish... The correspondence.

4. The calibration method for voltage-angle relationship of pitot tube with an anemometer in a gravity-based wind tunnel test according to claim 1, characterized in that: In step S2.4, the calibration process for the voltage angle correspondence of the negative angle sequence 3 of the wind tunnel bevel and the laser level is completed using the pitch mechanism of the wind tunnel bevel and the laser level: S2.4.1 Using the pitch mechanism of the wind tunnel bevel, adjust the bevel mechanism to the negative limit state of the pitch angle. ; S2.4.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung on the head of the anemometer pitot tube structure with measuring side slip angle. Under the action of the weight's gravity, the anemometer pitot tube with measuring side slip angle hangs down naturally in the negative direction. S2.4.3 Fine-tune the orientation of the pitot tube with measuring sideslip angle. Using a laser level, ensure the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the pitot tube with measuring sideslip angle is... ; S2.4.4 Using the wind tunnel bevel pitch mechanism, starting from the position of S2.4.3, the system moves at 1° intervals until the wind tunnel bevel reaches its positive pitch limit. There are a total of n pause points, and the output voltage of the anemometer airspeed pipeline with sideslip angle measurement is recorded under each pause point condition. The calibration angle of the airspeed tube channel with measuring sideslip angle corresponding to each pause point is: ; S2.4.5 Using the data obtained in S2.4.4, establish... The correspondence.

5. The calibration method for voltage-angle relationship of pitot tube with an anemometer in a gravity-based wind tunnel test according to claim 1, characterized in that: In step S2.5, the calibration process for the voltage angle correspondence of the wind tunnel bevel pitch mechanism and laser level, using the wind tunnel bevel pitch tube positive angle sequence 4 with sideslip angle measurement, is as follows: S2.5.1 Using the pitch mechanism of the wind tunnel bevel, the model's attitude angle is adjusted to the positive limit state of the pitch angle. ; S2.5.2 Using a thin copper wire with a diameter of 0.5 mm and a length of not less than 0.5 m, a 0.25 kg weight is suspended and stably hung at the tail of the anemometer pitot tube structure with measuring side slip angle. Under the action of the weight's gravity, the anemometer pitot tube with measuring side slip angle hangs down naturally in the positive direction. S2.5.3 Fine-tune the orientation of the anemometer pitot tube (sideslip angle). Using a laser level, ensure the vertical optical path of the laser level covers the entire copper wire. At this point, the calibrated angle of the anemometer pitot tube with the sideslip angle measurement function is... ; S2.5.4 Using the wind tunnel bend mechanism, starting from the position of S2.5.3, run at 1° intervals until the negative limit of the wind tunnel bend's pitch angle. There are a total of n pause points, and the output voltage of the anemometer pitot tube channel with sideslip angle measurement is recorded under each pause point condition. The calibration angle of the airspeed tube channel with measuring sideslip angle corresponding to each pause point is: ; S2.5.5 uses the data obtained from S2.5.4 to establish... The correspondence.

6. The calibration method for voltage-angle relationship of pitot tube with an anemometer in a gravity-based wind tunnel test according to claim 1, characterized in that: The wind tunnel bevel described in step S1 can independently complete two-degree-of-freedom operation of pitch and roll.

7. The calibration method for voltage-angle relationship of pitot tube with an anemometer in a gravity-based wind tunnel test according to claim 1, characterized in that: The laser level mentioned in step S1 is an opto-mechatronic instrument used to project horizontal, vertical, or cross-shaped laser reference lines.

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