Wind tunnel free-flight model support device for gust alleviation verification and test method

Abstract

The application provides a wind tunnel free flight model support device and test method for gust alleviation verification, and belongs to the technical field of aeroelastic wind tunnel test. The support device comprises: a linear guide rail vertically fixed between the upper wall of the wind tunnel and the lower wall of the wind tunnel; a synchronous toothed belt arranged along the linear guide rail, both ends of the synchronous toothed belt being mounted on a tunnel top belt wheel and a tunnel bottom belt wheel; a sliding block fixed on the synchronous toothed belt; a pitch electromagnetic damper comprising a pitch electromagnetic damper rotor and a pitch electromagnetic damper stator, the pitch electromagnetic damper stator being fixedly connected with the sliding block, and the pitch electromagnetic damper rotor being fixedly connected with a model airplane; and a heave electromagnetic damper arranged adjacent to the tunnel top belt wheel, the heave electromagnetic damper comprising a heave electromagnetic damper stator and a heave electromagnetic damper rotor, the heave electromagnetic damper rotor and the tunnel top belt wheel being meshed with each other to form a heave displacement conversion amplification gear pair.

Description

Technical Field

[0001] This application belongs to the field of aeroelastic wind tunnel testing technology, and specifically relates to a wind tunnel free-flight model support device and test method for gust mitigation verification. Background Technology

[0002] Large transport aircraft and heavy bombers that do not perform rapid maneuvers may experience gust loads on their structures that exceed the maneuver loads when encountering gusts. Prolonged exposure to these intensely varying gust loads can reduce the fatigue life of various aircraft components, decrease passenger comfort, and even impair pilot control, jeopardizing flight safety. Gust mitigation utilizes control technologies to reduce the dynamic loads on the airframe structure in gust environments, thereby reducing the aircraft's structural weight, increasing fatigue life, and improving passenger comfort.

[0003] The design and development of gust mitigation systems, in addition to numerical simulation, must rely on various tests. Since wind tunnel free-flight tests can fully simulate the response process of an aircraft after encountering gusts, gust mitigation wind tunnel free-flight tests, compared with other ground tests, can more comprehensively and fully verify the mathematical model of the controlled object, the gust mitigation design scheme, and the system function, and play an important supporting role in the development of aircraft gust mitigation systems.

[0004] The motion of an aircraft after being disturbed by gusts is a superposition of rigid body motion and elastic vibration. Atmospheric gusts are random disturbances with energy concentrated at low frequencies. Typically, the rigid body response of an aircraft after being disturbed by vertical gusts contributes the most to the structural load. Therefore, when conducting wind tunnel tests to mitigate gusts, a specialized support device is needed to simulate the rigid body motion of the test model (hereinafter referred to as the model aircraft). In addition to providing the corresponding rigid body motion stroke for the test model, the support device should also provide certain auxiliary protection functions for the model aircraft during the test. Especially during the start-up and shutdown phases of the gust generator, when the gust frequency changes from low to high or from high to low, if the gust frequency approaches or coincides with the long-period rigid body heave-and-float motion mode frequency of the model aircraft, the model aircraft will exhibit a large-amplitude heave-and-float motion response, which can easily exceed the heave-and-float motion stroke limit of the support device. This can lead to a collision between the model aircraft and the heave-and-float motion limit of the support device, resulting in instability and a test accident.

[0005] Among the existing wind tunnel model support devices, those used for aerodynamic force and pressure measurement cannot simulate the rigid body motion of model aircraft; the double-cable suspension support devices widely used in flutter tests can only simulate the elastic support boundary of the model due to the presence of suspension springs, and cannot provide the "free-free" boundary required for gust mitigation function verification tests. Summary of the Invention

[0006] The purpose of this application is to provide a wind tunnel free-flight model support device and test method for gust mitigation verification, so as to solve or alleviate at least one of the problems in the background art.

[0007] Firstly, the technical solution of this application is: a wind tunnel free-flight model support device for gust mitigation verification, comprising:

[0008] A vertically fixed linear guide rail is installed between the upper and lower walls of the wind tunnel;

[0009] A synchronous toothed belt is arranged along a linear guide rail, with its two ends mounted on a pulley at the top of the tunnel and a pulley at the bottom of the tunnel.

[0010] A slider fixed on a synchronous toothed belt;

[0011] A pitch electromagnetic damper having a pitch electromagnetic damper rotor and a pitch electromagnetic damper stator, wherein the pitch electromagnetic damper stator is fixedly connected to a slider and the pitch electromagnetic damper rotor is fixedly connected to a model airplane.

[0012] An electromagnetic damper for sinking and floating is arranged adjacent to the pulley on the tunnel top. The electromagnetic damper for sinking and floating includes a stator and a rotor. The rotor and the pulley on the tunnel top mesh with each other to form a pair of gears for sinking and floating displacement conversion and amplification.

[0013] Preferably, the top pulley is installed on the outer side of the upper wall of the wind tunnel, and the bottom pulley 1 is installed on the lower side of the lower wall of the wind tunnel.

[0014] Preferably, the pitch electromagnetic damper is a dual-rotor disc electromagnetic damper.

[0015] Preferably, the buoyancy electromagnetic damper is a single-rotor disc electromagnetic damper.

[0016] Preferably, the outer surface of the tunnel top pulley is provided with a gear structure, and the outer surface of the buoyancy electromagnetic damper rotor is also provided with a gear structure. The gear structure of the buoyancy electromagnetic damper rotor meshes with the gear structure of the tunnel top pulley to form a buoyancy displacement conversion and amplification gear pair.

[0017] On the other hand, this application provides a test method for verifying gust mitigation using a wind tunnel free-flight model support device as described above, the test method comprising:

[0018] Construct the motion equations of the model aircraft's gust response under the damping effect of the support device;

[0019] Constructing the state-space equations for the gust response of a model aircraft under gust input;

[0020] The heave displacement and pitch angle response of the model aircraft are calculated based on the gust response motion equation, the gust response state space equation and the gust input. The results are compared with the maximum heave displacement and pitch angle allowed by the model aircraft during the test to determine the correspondence between the heave and pitch damping coefficients that the support device should provide and the gust input.

[0021] The gust generator inside the wind tunnel is activated to generate the gust excitation required for the test. Based on the measured gust input and the corresponding relationship, the damping coefficient of the electromagnetic damper of the support device is adjusted in real time to ensure that the pitch and heave motion of the model aircraft is always within the allowable controllable range.

[0022] Preferably, the equation of motion for the gust response is:

[0023]

[0024] Where V0 is the wind tunnel inflow velocity;

[0025] z represents the floating and sinking displacement of the model aircraft. For the sinking and floating speed of the model airplane, The buoyancy acceleration of the model airplane;

[0026] θ is the pitch angle of the model aircraft. For the pitch rate of the model aircraft, The pitch acceleration of the model airplane;

[0027] Z α This is the dimensional derivative of the lift of the model aircraft with respect to the angle of attack.

[0028] This is the dimensional derivative of the lift of the model aircraft with respect to the rate of change of angle of attack.

[0029] Z q This is the dimensional derivative of the lift of the model aircraft with respect to the pitch rate.

[0030] M α The dimensional derivative of the pitching moment of a model aircraft with respect to the angle of attack;

[0031] The dimensional derivative of the pitching moment of a model aircraft with respect to the rate of change of angle of attack;

[0032] M q The dimensional derivative of the pitching moment of a model aircraft with respect to the pitching rate;

[0033]

[0034] Q represents the incoming air velocity pressure in the wind tunnel;

[0035] S W For reference area;

[0036] c A For reference chord length;

[0037] c z The damping coefficient of the buoyancy damper supporting the mechanism;

[0038] c θ The damping coefficient of the pitch damper supporting the mechanism;

[0039] This is the derivative of the lift coefficient of the model aircraft with respect to the angle of attack;

[0040] This is the derivative of the moment coefficient of the model aircraft about the pitch axis with respect to the angle of attack;

[0041] The derivative of the lift of the model aircraft with respect to the dimensionless rate of change of angle of attack;

[0042] This is the derivative of the moment coefficient of the model aircraft about the pitch axis with respect to the dimensionless rate of change of the angle of attack.

[0043] This is the derivative of the lift coefficient of the model aircraft with respect to the dimensionless pitch rate.

[0044] This is the derivative of the pitch moment coefficient of the model aircraft with respect to the dimensionless pitch rate.

[0045] Preferably, the gust response state-space equation is:

[0046]

[0047] y = Cx

[0048] in, Let x be the derivative of the state vector, and u be the state vector. g Let A be the input vector and y be the output vector. g C and C are the state matrix, input matrix, and output matrix, respectively;

[0049]

[0050] I is the identity matrix, and E, F, G, and J are the state matrix A and input matrix B used for assembly. g The intermediate transition variables for the output matrix C are defined as follows;

[0051]

[0052]

[0053] y = [zθ] T , Among them, w g For gust speed, Acceleration of gusts.

[0054] The wind tunnel free-flight model support device and test method for gust mitigation verification provided in this application have the following advantages:

[0055] a) The support device is equipped with both pitch electromagnetic dampers and buoyancy electromagnetic dampers. The excitation current of the electromagnetic dampers can be preset or changed in real time according to the test requirements. The damping torque output can be flexibly and conveniently controlled, and it is effectively applicable to complex and ever-changing aeroelastic dynamic test environments.

[0056] b) By using a synchronous belt drive in conjunction with a displacement amplification gear, the buoyancy linear motion of the model aircraft is amplified and converted into the angular motion of the electromagnetic damper rotor, which can effectively solve the problem of low buoyancy motion speed and difficulty in efficiently applying buoyancy damping force.

[0057] c) The rotor angular rate and angular displacement output by the electromagnetic damper are directly used as the heave and pitch motion feedback signals of the model aircraft after simple conversion, which are used for model aircraft control without the need to configure additional model aircraft attitude measurement sensors.

[0058] d) The safe movement range of the model aircraft can be preset according to the test requirements; during the test, when the pitch or buoyancy amplitude of the model aircraft exceeds the preset safety threshold, the model movement can be constrained by significantly increasing the excitation current of the damper, so as to achieve automatic protection of the model. Attached Figure Description

[0059] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0060] Figure 1 This is a schematic diagram of the support device for the wind tunnel free-flight model in this application.

[0061] Figure 2 This is a schematic diagram of the motion relationship of the wind tunnel model in this application.

[0062] Figure 3 This is a schematic diagram illustrating the process of solving the damping coefficient of the support device required for the test in this application.

[0063] Figure 4 This is a schematic diagram of the pitch angle response in one embodiment of this application.

[0064] Figure 5 This is a schematic diagram of the buoyancy displacement response in one embodiment of this application.

[0065] Figure label:

[0066] 100-Supporting Device

[0067] 101-Linear Guide

[0068] 102-Slider

[0069] 103-Pitch Electromagnetic Damper Rotor

[0070] 104-Pitch Electromagnetic Damper Stator

[0071] 105-Pitch Electromagnetic Damper

[0072] 106-Synchronous Toothed Belt

[0073] 107-Tunnel Top Pulley

[0074] 108-Floating Displacement Conversion Amplification Gear Pair

[0075] 109-Floating Electromagnetic Damper Stator

[0076] 110-Floating Electromagnetic Damper Rotor

[0077] 111-Floating Electromagnetic Damper

[0078] 112-Bottom of the Tunnel with Pulley

[0079] 200-model airplane

[0080] 201-Wind Tunnel Upper Wall

[0081] 202-Wind Tunnel Lower Wall Detailed Implementation

[0082] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0083] This application provides a wind tunnel free-flight model support device and test method for gust mitigation verification. By using linear guide rails and sliders with electromagnetic damping adjustment units, it can effectively simulate the "pitch-boom freedom" support boundary required in gust mitigation wind tunnel tests, while also adjusting the damping of the support system online in real time to meet the needs of model aircraft response suppression during gust generation device startup and shutdown and emergency protection during the test process.

[0084] like Figure 1As shown, the wind tunnel free-flight model support device 100 for gust mitigation verification provided in this application includes: a linear guide rail 101, a slider 102, a pitch electromagnetic damper 105, a synchronous toothed belt 106, a pulley at the top of the tunnel 107, a pulley at the bottom of the tunnel 112, a settling displacement conversion and amplification gear pair 108, and a settling electromagnetic damper 111.

[0085] The linear guide rail 101 is vertically fixed between the upper wall 202 and the lower wall 201 of the wind tunnel. The synchronous toothed belt 106 is set along the linear guide rail 101, and its upper and lower ends are respectively installed on the top pulley 107 on the outside of the upper wall 202 and the bottom pulley 112 on the lower side of the lower wall 201.

[0086] The slider 102 is fixed on the synchronous toothed belt 106. The pulley 107 at the top of the tunnel, the pulley 112 at the bottom of the tunnel, and the slider 102 constitute the synchronous belt drive system.

[0087] Among them, the pitch electromagnetic damper 105 is a dual-rotor disc electromagnetic damper, which has a pitch electromagnetic damper rotor 103 and a pitch electromagnetic damper stator 104. The pitch electromagnetic damper stator 104 is fixedly connected to the slider 102, and the pitch electromagnetic damper rotor 103 is fixedly connected to the model airplane 200.

[0088] The buoyancy electromagnetic damper 111 is arranged adjacent to the tunnel top pulley 107. The outer surface of the tunnel top pulley 107 is configured as a gear structure. The buoyancy electromagnetic damper 111 is a single-rotor disc electromagnetic damper, which includes a buoyancy electromagnetic damper stator 109 and a buoyancy electromagnetic damper rotor 110. The outer surface of the buoyancy electromagnetic damper rotor 110 is also configured as a gear structure. The gear structure of the buoyancy electromagnetic damper rotor 110 meshes with the gear structure of the tunnel top pulley 107 to form a buoyancy displacement conversion and amplification gear pair 108.

[0089] When a gust of wind blows into the model aircraft 200 inside the wind tunnel, the gust load on the model aircraft 200 is transmitted to the slider 102. The linear motion of the slider 102 is transmitted to the floating displacement conversion amplification gear pair 108 via the synchronous toothed belt 106 and amplified, and then converted into the rotational motion of the floating electromagnetic damper rotor 110 around the floating electromagnetic damper stator 109. At the same time, the pitch motion of the model aircraft 200 is converted into the rotational motion between the pitch electromagnetic damper rotor 103 and the pitch electromagnetic damper stator 104.

[0090] See Figure 2 As shown, based on the aforementioned support device 100, this application further provides a test method for verifying gust mitigation, the test method comprising the following steps:

[0091] Step 1: Based on the model aircraft's mass m, moment of inertia J about the pitch axis of the model support device, distance d from the model aircraft's center of mass to the pitch axis of the support device, and the model aircraft's aerodynamic derivative, establish the model aircraft's gust response motion equation considering the damping effect of the support device:

[0092]

[0093] Where V0 is the wind tunnel inflow velocity;

[0094] z represents the floating and sinking displacement of the model aircraft. For the sinking and floating speed of the model airplane, The buoyancy acceleration of the model airplane;

[0095] θ is the pitch angle of the model aircraft. For the pitch rate of the model aircraft, The pitch acceleration of the model airplane;

[0096] Z α This is the dimensional derivative of the lift of the model aircraft with respect to the angle of attack.

[0097] This is the dimensional derivative of the lift of the model aircraft with respect to the rate of change of angle of attack.

[0098] Z q This is the dimensional derivative of the lift of the model aircraft with respect to the pitch rate.

[0099] M α The dimensional derivative of the pitching moment of a model aircraft with respect to the angle of attack;

[0100] The dimensional derivative of the pitching moment of a model aircraft with respect to the rate of change of angle of attack;

[0101] M q The dimensional derivative of the pitching moment of a model aircraft with respect to the pitching rate;

[0102]

[0103] Q represents the incoming air velocity pressure in the wind tunnel;

[0104] S W For reference area;

[0105] c A For reference chord length;

[0106] c z The damping coefficient of the buoyancy damper supporting the mechanism;

[0107] c θ The damping coefficient of the pitch damper supporting the mechanism;

[0108] This is the derivative of the lift coefficient of the model aircraft with respect to the angle of attack;

[0109] This is the derivative of the moment coefficient of the model aircraft about the pitch axis with respect to the angle of attack;

[0110] The derivative of the lift of the model aircraft with respect to the dimensionless rate of change of angle of attack;

[0111] This is the derivative of the moment coefficient of the model aircraft about the pitch axis with respect to the dimensionless rate of change of the angle of attack.

[0112] This is the derivative of the lift coefficient of the model aircraft with respect to the dimensionless pitch rate.

[0113] This is the derivative of the pitch moment coefficient of the model aircraft with respect to the dimensionless pitch rate;

[0114] Step 2: Establish the state-space equations for the gust response of the model aircraft to gust input:

[0115]

[0116] y = Cx

[0117] in, Let x be the derivative of the state vector, and u be the state vector. g Let A be the input vector and y be the output vector. g C and C are the state matrix, input matrix, and output matrix, respectively;

[0118]

[0119] I is the identity matrix, and E, F, G, and J are the state matrix A and input matrix B used for assembly. g The intermediate transition variables for the output matrix C are defined as follows;

[0120]

[0121]

[0122] y = [z θ] T , Among them, w g For gust speed, Acceleration of gusts;

[0123] Step 3, as follows Figure 3 As shown, based on the gust speed w input during the experiment... gThe model aircraft's heave displacement and pitch angle response were calculated using the model aircraft's gust response motion equation and gust response state space equation. The results were compared with the maximum heave displacement and pitch angle allowed by the model aircraft during the test. Based on the comparison results, the correspondence between the heave and pitch damping coefficients that the support device should provide and the input gust speed was determined.

[0124] Step 4: Start the wind tunnel. Activate the gust generator inside the wind tunnel to generate the gust excitation required for the test. Based on the measured gust input and the correspondence given in Step 3, adjust the damping coefficient of the electromagnetic damper of the support device in real time to ensure that the pitch and heave motion of the model aircraft is always within the allowable and controllable range.

[0125] For example, in the embodiment of the wind tunnel free-flight model test method of this application, the mass of the model aircraft is known to be m = 30 kg, and the moment of inertia about the pitch axis of the model support device is J = 15 kg·m. 2 The distance from the model aircraft's center of gravity to the pitch axis of the support device is d = 0.1m; the wind tunnel inflow velocity and pressure are Q = 980Pa; the reference area is S. W =3m 2 Reference chord length c A =1m, aerodynamic derivative The initial damping coefficient c of the electromagnetic damper z =0, c θ =0; the maximum allowable pitch angle and maximum heave displacement amplitude range during the test is θ. max =±5°, z max =±1.0m.

[0126] Based on the given parameters of the model aircraft, establish the state-space equation for the gust response of the model aircraft.

[0127]

[0128] y = Cx

[0129] Typically, the model aircraft exhibits the greatest response during the start-up and shutdown phases of the cascade gust generator. The gust speed during these phases can be simulated using an equivalent Chirp frequency modulation signal. The time required for the cascade to accelerate from rest to a stable operating frequency of 1 Hz is 30 seconds, and the gust speed amplitude during startup is approximately 1 m / s. Based on the established gust response state-space equations and the gust input generated during the start-up phase of the cascade gust generator, the heave displacement and pitch angle responses of the model aircraft are obtained, as shown in the appendix. Figure 4 and Figure 5 As shown, the amplitude of the model aircraft's heave displacement exceeds the maximum value allowed by the test, and the initial damping coefficient of the electromagnetic damper of the support device needs to be adjusted.

[0130] Based on the maximum allowable pitch angle and maximum heave displacement amplitude range during the test, the damping coefficient of the heave damper is increased to c. z =20, c θ =0 remains unchanged; see appendix for further details. Figure 4 and Figure 5 At this time, during the process of the gust generator starting up and transitioning to a stable operating frequency, the amplitude of the model aircraft's heave displacement and pitch angle response are both lower than the maximum allowable value. The test can be carried out normally in the stable operating frequency band of the gust generator, and the damping coefficient of the support device damper can be adjusted again as needed.

[0131] The wind tunnel free-flight model support device and test method for gust mitigation verification provided in this application have the following advantages:

[0132] a) The support device is equipped with both pitch electromagnetic dampers and buoyancy electromagnetic dampers. The excitation current of the electromagnetic dampers can be preset or changed in real time according to the test requirements. The damping torque output can be flexibly and conveniently controlled, and it is effectively applicable to complex and ever-changing aeroelastic dynamic test environments.

[0133] b) By using a synchronous belt drive in conjunction with a displacement amplification gear, the buoyancy linear motion of the model aircraft is amplified and converted into the angular motion of the electromagnetic damper rotor, which can effectively solve the problem of low buoyancy motion speed and difficulty in efficiently applying buoyancy damping force.

[0134] c) The rotor angular rate and angular displacement output by the electromagnetic damper are directly used as the heave and pitch motion feedback signals of the model aircraft after simple conversion, which are used for model aircraft control without the need to configure additional model aircraft attitude measurement sensors.

[0135] d) The safe movement range of the model aircraft can be preset according to the test requirements; during the test, when the pitch or buoyancy amplitude of the model aircraft exceeds the preset safety threshold, the model movement can be constrained by significantly increasing the excitation current of the damper, so as to achieve automatic protection of the model.

[0136] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A test method for verifying gust mitigation using a wind tunnel free-flight model support device, characterized in that, The wind tunnel free-flight model support device includes: A vertically fixed linear guide rail is installed between the upper and lower walls of the wind tunnel; A synchronous toothed belt is arranged along a linear guide rail, with its two ends mounted on a pulley at the top of the tunnel and a pulley at the bottom of the tunnel. A slider fixed on a synchronous toothed belt; A pitch electromagnetic damper having a pitch electromagnetic damper rotor and a pitch electromagnetic damper stator, wherein the pitch electromagnetic damper stator is fixedly connected to a slider and the pitch electromagnetic damper rotor is fixedly connected to a model airplane. An electromagnetic damper for sinking and floating is arranged adjacent to the pulley on the tunnel top. The electromagnetic damper for sinking and floating includes a stator and a rotor. The rotor and the pulley on the tunnel top mesh with each other to form a pair of gears for sinking and floating displacement conversion and amplification. The test method includes: Construct the motion equations of the model aircraft's gust response under the damping effect of the support device; Constructing the state-space equations for the gust response of a model aircraft under gust input; The heave displacement and pitch angle response of the model aircraft are calculated based on the gust response motion equation, the gust response state space equation and the gust input. The results are compared with the maximum heave displacement and pitch angle allowed by the model aircraft during the test to determine the correspondence between the heave and pitch damping coefficients that the support device should provide and the gust input. The gust generator inside the wind tunnel is activated to generate the gust excitation required for the test. Based on the measured gust input and the corresponding relationship, the damping coefficient of the electromagnetic damper of the support device is adjusted in real time to ensure that the pitch and heave motion of the model aircraft is always within the allowable controllable range.

2. The test method as described in claim 1, characterized in that, The equation of motion for the gust response is: ; Where V0 is the wind tunnel inflow velocity; z represents the floating and sinking displacement of the model aircraft. The floating and sinking displacement velocity of the model aircraft. Acceleration for buoyancy and sinking of the model airplane; For the pitch angle of the model airplane, For the pitch rate of the model aircraft, The pitch acceleration of the model airplane; This is the dimensional derivative of the lift of the model aircraft with respect to the angle of attack. This is the dimensional derivative of the lift of the model aircraft with respect to the rate of change of angle of attack. This is the dimensional derivative of the lift of the model aircraft with respect to the pitch rate. The dimensional derivative of the pitching moment of a model aircraft with respect to the angle of attack; The dimensional derivative of the pitching moment of a model aircraft with respect to the rate of change of angle of attack; The dimensional derivative of the pitching moment of a model aircraft with respect to the pitching rate; ， ， ， ， ， ； The airflow velocity pressure in the wind tunnel; For reference area; For reference chord length; The damping coefficient of the buoyancy damper supporting the mechanism; The damping coefficient of the pitch damper supporting the mechanism; This is the derivative of the lift coefficient of the model aircraft with respect to the angle of attack; This is the derivative of the moment coefficient of the model aircraft about the pitch axis with respect to the angle of attack; The derivative of the lift of the model aircraft with respect to the dimensionless rate of change of angle of attack; This is the derivative of the moment coefficient of the model aircraft about the pitch axis with respect to the dimensionless rate of change of the angle of attack. This is the derivative of the lift coefficient of the model aircraft with respect to the dimensionless pitch rate. This is the derivative of the pitch moment coefficient of the model aircraft with respect to the dimensionless pitch rate.

3. The test method as described in claim 2, characterized in that, The state-space equation for the gust response is: ; in, Let x be the derivative of the state vector. u g Let A be the input vector and y be the output vector. g C and C are the state matrix, input matrix, and output matrix, respectively; ； ； ； Let E be the identity matrix, and F, G, and J be the matrices used to assemble the state matrix A and the input matrix B. g The intermediate transition variables for the output matrix C are defined as follows; ， ， ， ， , , ,in, For gust speed, Acceleration of gusts.

4. The test method as described in claim 1, characterized in that, The top pulley is installed on the outer side of the upper wall of the wind tunnel, and the bottom pulley is installed on the lower side of the lower wall of the wind tunnel.

5. The test method as described in claim 1, characterized in that, The pitch electromagnetic damper is a dual-rotor disc electromagnetic damper.

6. The test method as described in claim 5, characterized in that, The buoyancy electromagnetic damper is a single-rotor disc electromagnetic damper.

7. The test method as described in claim 6, characterized in that, The outer surface of the pulley on the tunnel top is provided with a gear structure, and the outer surface of the buoyancy electromagnetic damper rotor is also provided with a gear structure. The gear structure of the buoyancy electromagnetic damper rotor meshes with the gear structure of the pulley on the tunnel top to form a buoyancy displacement conversion and amplification gear pair.

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