A device and method for automatically adjusting the fluctuation speed of air flow with wind speed

Abstract

A device and method for automatically adjusting airflow fluctuation speed with wind speed variation, the device comprising a grid blade, a grid blade mounting mechanism, a grid blade horizontal righting mechanism, a grid blade flapping vibration execution mechanism and a grid blade flapping amplitude adjusting mechanism; the grid blade mounting mechanism is fixed in a wind tunnel; the grid blade is arranged on the grid blade mounting mechanism; the grid blade horizontal righting mechanism is located above the wind tunnel and connected with the grid blade mounting mechanism; the grid blade flapping vibration execution mechanism is located below the wind tunnel, and the grid blade flapping amplitude adjusting mechanism is arranged on the grid blade flapping vibration execution mechanism and connected with the grid blade through a transmission connecting rod. The present application eliminates the replacement process of traditional damping net and grid, improves the test efficiency and normalization, can automatically adjust the airflow fluctuation speed according to the wind speed variation, realizes the purpose of keeping the turbulence intensity basically constant under different wind speed conditions, and effectively improves the accuracy and reliability of test data.

Description

Technical Field

[0001] This invention belongs to the field of wind tunnel testing technology, and in particular relates to a device and method for automatically adjusting the airflow pulsation speed according to wind speed changes. Background Technology

[0002] As a fundamental infrastructure for aerodynamic characteristic research, low-speed wind tunnels directly impact the reliability of test data from aircraft, automobiles, and building models due to their flow field quality. Turbulence, as one of the core flow field parameters, needs to be precisely controlled according to different test scenarios, such as laminar airfoil testing and atmospheric boundary layer simulation, and it needs to remain low and stable within the same test.

[0003] Turbulence intensity is expressed as the ratio of the root mean square of the fluctuating velocity to the time-averaged velocity. The time-averaged velocity represents the steady-state portion of the flow, neglecting the instantaneous fluctuations caused by turbulence. In wind tunnel tests, even if turbulence exists, the time-averaged velocity may remain constant. The fluctuating velocity represents the random fluctuation of energy in turbulence. In wind tunnel tests, even if the time-averaged velocity is stable, severe fluctuations may still occur locally due to separation vortices, shear layers, etc.

[0004] Currently, traditional turbulence control techniques heavily rely on damping nets and grids. Under the same wind speed conditions, turbulence needs to be adjusted by replacing damping nets and grids. This results in problems such as cumbersome replacement, reduced test efficiency, and poor normalization. If damping nets and grids are not replaced, turbulence will decrease as wind speed increases, thus affecting the accuracy and reliability of test data. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a device and method for automatically adjusting the airflow pulsation velocity according to wind speed changes. This eliminates the need for replacing traditional damping nets, grids, etc., effectively improving test efficiency and normalization. It can automatically adjust the airflow pulsation velocity according to the wind speed changes in the wind tunnel, thereby achieving the goal of maintaining a basically constant turbulence intensity under different wind speed conditions, effectively improving the accuracy and reliability of test data.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a device for automatically adjusting the airflow pulsation speed according to wind speed changes, comprising grid blades, a grid blade mounting frame mechanism, a grid blade horizontal straightening mechanism, a grid blade flapping wing vibration actuator, and a grid blade flapping wing amplitude adjustment mechanism; the grid blade mounting frame mechanism is fixedly installed inside a wind tunnel; the number of grid blades is several, and the grid blades are evenly distributed on the grid blade mounting frame mechanism along the height direction of the wind tunnel, and the extension ends of all grid blades on the leading edge side are connected in series by a transmission link, and the grid blades are hinged to the transmission link; the grid blade horizontal straightening mechanism is located above the wind tunnel and is connected to the grid blade mounting frame mechanism; the grid blade flapping wing vibration actuator is located below the wind tunnel, and the grid blade flapping wing amplitude adjustment mechanism is disposed on the grid blade flapping wing vibration actuator and is connected to the transmission link.

[0007] The grid blade mounting bracket mechanism includes a guide stationary slide rail and a lifting movable slide rail; the guide stationary slide rail is vertically fixed to the inner surface of the wind tunnel side wall panel; the lifting movable slide rail is vertically inserted into the guide stationary slide rail, and the lifting movable slide rail has only linear lifting freedom relative to the guide stationary slide rail, and the lifting movable slide rail extends upward through the wind tunnel top wall panel; the elongation end of the leading edge side of the grid blade is hinged to the lifting movable slide rail.

[0008] The horizontal straightening mechanism for the grid blades includes a straightening motor, a lead screw, a lead screw nut, and a force transmission plate. The straightening motor is vertically fixed above the wind tunnel, with its motor shaft facing downwards. The upper end of the lead screw is coaxially and fixedly connected to the motor shaft of the straightening motor via a coupling, and the lower end of the lead screw is rotatably connected to the outer surface of the wind tunnel top wall via a bearing seat. The lead screw nut is fitted onto the lead screw and is fixedly connected to the force transmission plate. The force transmission plate is horizontally positioned, and its end is fixedly connected to the upper end of the lifting sliding rail.

[0009] The grid blade flapping vibration actuator includes a flapping vibration actuator motor and a rotary disk; the flapping vibration actuator motor is horizontally fixed below the wind tunnel; the rotary disk is vertically arranged, and the center of the rotary disk is fixedly connected to the motor shaft of the flapping vibration actuator motor.

[0010] The flapping amplitude adjustment mechanism for the grid blades includes a flapping amplitude adjustment motor, a gear, a rack, a slider, a guide rail, and a force transmission rod. The guide rail is fixedly installed on the surface of a rotating disk, and is radially distributed along the disk. One end of the guide rail is located at the center of the rotating disk, and the other end is located at the edge of the disk. The slider is mounted on the guide rail and has only linear freedom relative to the guide rail. The flapping amplitude adjustment motor is fixedly installed on the slider, and its motor shaft is perpendicular to the guide rail. One end of the force transmission rod is hinged to the housing of the flapping amplitude adjustment motor, and the other end is hinged to the bottom end of a transmission connecting rod. The rack is fixedly installed on the surface of the rotating disk and is parallel to the guide rail. The gear is coaxially fixed on the motor shaft of the flapping amplitude adjustment motor, and meshes with the rack.

[0011] A method for automatically adjusting airflow pulsation speed according to wind speed changes, employing the aforementioned device for automatically adjusting airflow pulsation speed according to wind speed changes, includes the following steps:

[0012] Step 1: Set the flapping amplitude of the grid blades. First, start the flapping vibration actuator motor to drive the rotary disk to rotate until the guide rail is in a vertical position and located in the upper half of the rotary disk.

[0013] Step 2: Start the flapping wing amplitude adjustment motor, which drives the gear to rotate. The rotational motion of the gear will be converted into rolling motion along the rack, which in turn drives the flapping wing amplitude adjustment motor and the slider to move linearly along the guide rail until the transmission rod drives the transmission link to move upward by half the flapping wing amplitude. At this time, the grid blades will deflect around the hinge point between them and the lifting slide rail, so that the grid blades change from a horizontal state to a downward deflection state.

[0014] Step 3: Start the straightening motor to drive the lead screw to rotate. The rotational motion of the lead screw will be synchronously converted into the linear motion of the lead screw nut. The lead screw nut drives the force transmission plate to move down synchronously, which in turn drives the lifting sliding rail to move up along the guide stationary sliding rail. At the same time, it drives the grid blades to deflect around the hinge point between the grid blades and the transmission link until the grid blades return to the horizontal state from the downward deflection state.

[0015] Step 4: Select a test point at the center of the test section of the wind tunnel, and install a hot wire probe at the selected test point. The distance between the test point and the grid blade should not be less than 10 times the chord length of the grid blade.

[0016] Step 5: Start the wind tunnel and adjust the wind speed to the set value. Then, the hot wire probe at the test point will measure the airflow pulsation velocity in real time and convert the measured airflow pulsation velocity into airflow turbulence.

[0017] Step 6: Start the flapping wing vibration actuator motor to drive the rotary disc to rotate. The rotary disc drives the transmission link to move up and down reciprocatingly through the force transmission rod, which in turn drives the grid blades to flap around the hinge point between the grid blades and the lifting slide rail.

[0018] Step 7: Change the speed of the flapping wing vibration actuator motor to adjust the flapping wing vibration frequency of the grid blades, thereby changing the airflow pulsation speed and thus changing the airflow turbulence intensity until the measured airflow turbulence intensity matches the set target turbulence intensity.

[0019] Step 8: Repeat steps 1 to 7, except that the wind speed setting remains unchanged, but the flapping amplitude setting and the target turbulence setting of the grid blades are changed.

[0020] Step 9: Repeat steps 1 through 8, the difference being that you adjust the wind speed setting.

[0021] Step 10: Establish a database of wind speed, grating blade flapping amplitude, grating blade flapping frequency, and target turbulence intensity;

[0022] Step 11: When conducting wind tunnel tests, input the target turbulence intensity. Based on the changes in wind speed, automatically match the corresponding flapping amplitude and vibration frequency of the grid blades from the database, so that the airflow turbulence intensity in the wind tunnel is automatically adjusted to the target value.

[0023] The beneficial effects of this invention are:

[0024] The device and method for automatically adjusting the airflow pulsation velocity according to wind speed changes of the present invention eliminates the need for replacement of traditional damping nets, grids, etc., and can effectively improve test efficiency and normalization. It can automatically adjust the airflow pulsation velocity according to the wind speed changes in the wind tunnel, thereby achieving the goal of maintaining a basically constant turbulence intensity under different wind speed conditions, and effectively improving the accuracy and reliability of test data. Attached Figure Description

[0025] Figure 1 This is a front view of a device for automatically adjusting the airflow pulsation speed according to changes in wind speed, according to the present invention.

[0026] Figure 2 This is a side view of a device for automatically adjusting the airflow pulsation speed according to changes in wind speed according to the present invention;

[0027] Figure 3 This is a front view of the grille blade flapping amplitude adjustment mechanism of the present invention;

[0028] Figure 4 This is a side view of the assembly of the grille blade flapping wing amplitude adjustment mechanism and the grille blade flapping wing vibration actuator of the present invention;

[0029] In the diagram, 1—grid blade, 2—transmission link, 3—wind tunnel, 4—guide stationary slide rail, 5—lifting slide rail, 6—straightening motor, 7—lead screw, 8—lead nut, 9—force transmission plate, 10—flapping wing vibration actuator motor, 11—rotary disc, 12—flapping wing amplitude adjustment motor, 13—gear, 14—rack, 15—slider, 16—guide rail, 17—force transmission rod. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0031] like Figures 1-4 As shown, a device for automatically adjusting airflow pulsation speed according to wind speed changes includes grid blades 1, a grid blade mounting frame mechanism, a grid blade horizontal straightening mechanism, a grid blade flapping wing vibration actuator, and a grid blade flapping wing amplitude adjustment mechanism. The grid blade mounting frame mechanism is fixedly installed inside a wind tunnel 3. A plurality of grid blades 1 are distributed at equal intervals along the height direction of the wind tunnel 3 on the grid blade mounting frame mechanism. The elongated ends of all grid blades 1 on their leading edges are connected in series by a transmission link 2, and the grid blades 1 and the transmission link 2 are hinged together. The grid blade horizontal straightening mechanism is located above the wind tunnel 3 and is connected to the grid blade mounting frame mechanism. The grid blade flapping wing vibration actuator is located below the wind tunnel 3, and the grid blade flapping wing amplitude adjustment mechanism is mounted on the grid blade flapping wing vibration actuator and is connected to the transmission link 2.

[0032] The grid blade mounting bracket mechanism includes a guide stationary slide rail 4 and a lifting movable slide rail 5; the guide stationary slide rail 4 is vertically fixed to the inner surface of the side wall panel of the wind tunnel 3; the lifting movable slide rail 5 is vertically inserted into the guide stationary slide rail 4, and the lifting movable slide rail 5 has only linear lifting freedom relative to the guide stationary slide rail 4, and the lifting movable slide rail 5 extends upward through the top wall panel of the wind tunnel 3; the elongated end of the leading edge side of the grid blade 1 is hinged to the lifting movable slide rail 5.

[0033] The horizontal straightening mechanism for the grid blades includes a straightening motor 6, a lead screw 7, a lead screw nut 8, and a force transmission plate 9. The straightening motor 6 is vertically fixed above the wind tunnel 3, with its motor shaft facing downwards. The upper end of the lead screw 7 is coaxially and fixedly connected to the motor shaft of the straightening motor 6 via a coupling, and the lower end of the lead screw 7 is rotatably connected to the outer surface of the top wall panel of the wind tunnel 3 via a bearing seat. The lead screw nut 8 is fitted onto the lead screw 7 and is fixedly connected to the force transmission plate 9. The force transmission plate 9 is horizontally positioned, and its end is fixedly connected to the upper end of the lifting sliding rail 5.

[0034] The grid blade flapping vibration actuator includes a flapping vibration actuator motor 10 and a rotary disk 11; the flapping vibration actuator motor 10 is horizontally fixed below the wind tunnel 3; the rotary disk 11 is vertically arranged, and the center of the rotary disk 11 is fixedly connected to the motor shaft of the flapping vibration actuator motor 10.

[0035] The flapping amplitude adjustment mechanism for the grid blades includes a flapping amplitude adjustment motor 12, a gear 13, a rack 14, a slider 15, a guide rail 16, and a force transmission rod 17. The guide rail 16 is fixedly mounted on the surface of the rotating disk 11, and is radially distributed along the disk. One end of the guide rail 16 is located at the center of the rotating disk 11, and the other end is located at the edge of the disk 11. The slider 15 is mounted on the guide rail 16 and has only linear freedom of movement relative to the guide rail 16. The flapping amplitude adjustment motor 12 is fixedly mounted on the slider 15, and the motor shaft of the flapping amplitude adjustment motor 12 is perpendicular to the guide rail 16; one end of the force transmission rod 17 is hinged to the housing of the flapping amplitude adjustment motor 12, and the other end of the force transmission rod 17 is hinged to the bottom end of the transmission connecting rod 2; the rack 14 is fixedly mounted on the surface of the rotary disk 11, and the rack 14 is parallel to the guide rail 16; the gear 13 is coaxially fixed on the motor shaft of the flapping amplitude adjustment motor 12, and the gear 13 meshes with the rack 14.

[0036] In this embodiment, the cross-sectional shape of the wind tunnel 3 is a rectangle of 1m×1.2m, the maximum wind speed of the wind tunnel 3 is 50m / s, the original turbulence intensity of the wind tunnel 3 is 0.1%, the number of grid blades 1 is 18, the spacing between adjacent grid blades 1 is 50mm, the chord length of the grid blades 1 is 200mm, and the radius of the rotating disk 11 is 80mm.

[0037] A method for automatically adjusting airflow pulsation speed according to wind speed changes, employing the aforementioned device for automatically adjusting airflow pulsation speed according to wind speed changes, includes the following steps:

[0038] Step 1: Set the flapping amplitude of the grid blade 1. First, start the flapping vibration actuator motor 10 to drive the rotary disk 11 to rotate until the guide rail 16 is in a vertical state and located in the upper half of the rotary disk 11.

[0039] Step 2: Start the flapping wing amplitude adjustment motor 12, which drives the gear 13 to rotate. The rotational motion of the gear 13 will be synchronously converted into the rolling motion along the rack 14, which in turn drives the flapping wing amplitude adjustment motor 12 and the slider 15 to move linearly along the guide rail 16 until the transmission rod 17 drives the transmission connecting rod 2 to move upward by half the flapping wing amplitude. At this time, the grid blade 1 will deflect around its hinge point with the lifting sliding rail 5, so that the grid blade 1 changes from a horizontal state to a downward deflection state.

[0040] Step 3: Start the straightening motor 6, which drives the lead screw 7 to rotate. The rotational motion of the lead screw 7 will be synchronously converted into the linear motion of the lead screw nut 8. Through the lead screw nut 8, the force transmission plate 9 will move down synchronously, which in turn drives the lifting sliding rail 5 to move up along the guide stationary sliding rail 4. At the same time, it drives the grid blade 1 to deflect around the hinge point between it and the transmission link 2 until the grid blade 1 returns from the downward deflection state to the horizontal state.

[0041] Step 4: Select a test point at the center of the test section of wind tunnel 3, and install a hot wire probe at the selected test point. The distance between the test point and the grid blade 1 shall not be less than 10 times the chord length of the grid blade 1. In this embodiment, the distance between the test point and the grid blade 1 is 2000mm.

[0042] Step 5: Start wind tunnel 3, adjust the wind speed to the set value, and then use the hot wire probe at the test point to measure the airflow pulsation velocity in real time. After that, the measured airflow pulsation velocity is synchronously converted into airflow turbulence.

[0043] Step 6: Start the flapping wing vibration actuator motor 10, which drives the rotary disk 11 to rotate. The rotary disk 11 drives the transmission connecting rod 2 to move up and down through the force transmission rod 17, which in turn drives the grid blades 1 to flap around the hinge point between them and the lifting sliding rail 5.

[0044] Step 7: Change the rotation speed of the flapping wing vibration actuator motor 10 to adjust the flapping wing vibration frequency of the grid blade 1, thereby changing the airflow pulsation speed and thus changing the airflow turbulence intensity until the measured airflow turbulence intensity matches the set target turbulence intensity.

[0045] Step 8: Repeat steps 1 to 7, except that the wind speed setting remains unchanged, but the flapping amplitude setting and the target turbulence setting of the grid blade 1 are changed.

[0046] In this embodiment, the wind speed is set to 10 m / s;

[0047] When the target turbulence intensity is set to 0.2%, the flapping amplitude of the grid blade 1 is set to 3.2 mm, and the flapping frequency of the grid blade 1 is 120 Hz.

[0048] When the target turbulence intensity is set to 0.4%, the flapping amplitude of the grid blade 1 is set to 12.4 mm, and the flapping frequency of the grid blade 1 is 86 Hz.

[0049] When the target turbulence intensity is set to 0.6%, the flapping amplitude of the grid blade 1 is set to 20.6 mm, and the flapping frequency of the grid blade 1 is 140 Hz.

[0050] When the target turbulence intensity is set to 0.8%, the flapping amplitude of the grid blade 1 is set to 26.8 mm, and the flapping frequency of the grid blade 1 is 56 Hz.

[0051] When the target turbulence intensity is set to 1%, the flapping amplitude of the grid blade 1 is set to 30.2 mm, and the flapping frequency of the grid blade 1 is 78 Hz.

[0052] When the target turbulence intensity is set to 1.2%, the flapping amplitude of the grid blade 1 is set to 32.8 mm, and the flapping frequency of the grid blade 1 is 92 Hz.

[0053] When the target turbulence intensity is set to 1.4%, the flapping amplitude of the grid blade 1 is set to 34.4 mm, and the flapping frequency of the grid blade 1 is 45 Hz.

[0054] When the target turbulence intensity is set to 1.6%, the flapping amplitude of the grid blade 1 is set to 35.6 mm, and the flapping frequency of the grid blade 1 is 105 Hz.

[0055] When the target turbulence intensity is set to 1.8%, the flapping amplitude of the grid blade 1 is set to 37.4 mm, and the flapping frequency of the grid blade 1 is 98 Hz.

[0056] When the target turbulence intensity is set to 2%, the flapping amplitude of the grid blade 1 is set to 38.2 mm, and the flapping frequency of the grid blade 1 is 60 Hz.

[0057] Step 9: Repeat steps 1 through 8, the difference being that you adjust the wind speed setting.

[0058] In this embodiment, the adjusted wind speed settings are 15m / s, 20m / s, 25m / s, 30m / s, 35m / s, 40m / s, 45m / s and 50m / s respectively;

[0059] Step 10: Establish a database of wind speed, flapping amplitude of grid blade 1, vibration frequency of grid blade 1, and target turbulence intensity;

[0060] Step 11: When conducting wind tunnel tests, input the target turbulence intensity. Based on the wind speed changes, automatically match the corresponding flapping amplitude and vibration frequency of the grid blade 1 from the database, so that the airflow turbulence intensity in wind tunnel 3 is automatically adjusted to the target value.

[0061] The solutions in the embodiments are not intended to limit the scope of protection of the present invention. All equivalent implementations or modifications that do not depart from the present invention are included in the scope of protection of the present invention.

Claims

1. A device for automatically adjusting the airflow pulsation speed according to wind speed changes, characterized in that: The system includes grid blades, a grid blade mounting frame mechanism, a grid blade horizontal alignment mechanism, a grid blade flapping wing vibration actuator, and a grid blade flapping wing amplitude adjustment mechanism. The grid blade mounting frame mechanism is fixedly installed inside the wind tunnel. A number of grid blades are distributed at equal intervals along the height of the wind tunnel on the grid blade mounting frame mechanism. The leading edges of all grid blades are connected in series by a transmission link, and the grid blades are hinged to the transmission link. The grid blade horizontal alignment mechanism is located above the wind tunnel and is connected to the grid blade mounting frame mechanism. The grid blade flapping wing vibration actuator is located below the wind tunnel, and the grid blade flapping wing amplitude adjustment mechanism is mounted on the actuator and connected to the transmission link. The grid blade mounting bracket mechanism includes a guide stationary slide rail and a lifting movable slide rail; the guide stationary slide rail is vertically fixed to the inner surface of the wind tunnel side wall panel; the lifting movable slide rail is vertically inserted into the guide stationary slide rail, and the lifting movable slide rail has only linear lifting freedom relative to the guide stationary slide rail, and the lifting movable slide rail extends upward through the wind tunnel top wall panel; the elongation end of the leading edge side of the grid blade is hinged to the lifting movable slide rail; The horizontal straightening mechanism for the grid blades includes a straightening motor, a lead screw, a lead screw nut, and a force transmission plate. The straightening motor is vertically fixed above the wind tunnel, with its motor shaft facing downwards. The upper end of the lead screw is coaxially and fixedly connected to the motor shaft of the straightening motor via a coupling, and the lower end of the lead screw is rotatably connected to the outer surface of the wind tunnel top wall panel via a bearing seat. The lead screw nut is fitted onto the lead screw and is fixedly connected to the force transmission plate. The force transmission plate is horizontally positioned, and its end is fixedly connected to the upper end of the lifting sliding rail. The grid blade flapping vibration actuator includes a flapping vibration actuator motor and a rotary disk; the flapping vibration actuator motor is horizontally fixed below the wind tunnel; the rotary disk is vertically arranged, and the center of the rotary disk is fixedly connected to the motor shaft of the flapping vibration actuator motor. The flapping amplitude adjustment mechanism for the grid blades includes a flapping amplitude adjustment motor, a gear, a rack, a slider, a guide rail, and a force transmission rod. The guide rail is fixedly installed on the surface of a rotating disk, and is radially distributed along the disk. One end of the guide rail is located at the center of the rotating disk, and the other end is located at the edge of the disk. The slider is mounted on the guide rail and has only linear freedom relative to the guide rail. The flapping amplitude adjustment motor is fixedly installed on the slider, and its motor shaft is perpendicular to the guide rail. One end of the force transmission rod is hinged to the housing of the flapping amplitude adjustment motor, and the other end is hinged to the bottom end of a transmission connecting rod. The rack is fixedly installed on the surface of the rotating disk and is parallel to the guide rail. The gear is coaxially fixed on the motor shaft of the flapping amplitude adjustment motor, and meshes with the rack.

2. A method for automatically adjusting airflow pulsation speed according to wind speed changes, employing the device for automatically adjusting airflow pulsation speed according to wind speed changes as described in claim 1, characterized in that... Includes the following steps: Step 1: Set the flapping amplitude of the grid blades. First, start the flapping vibration actuator motor to drive the rotary disk to rotate until the guide rail is in a vertical position and located in the upper half of the rotary disk. Step 2: Start the flapping wing amplitude adjustment motor, which drives the gear to rotate. The rotational motion of the gear will be converted into rolling motion along the rack, which in turn drives the flapping wing amplitude adjustment motor and the slider to move linearly along the guide rail until the transmission rod drives the transmission link to move upward by half the flapping wing amplitude. At this time, the grid blades will deflect around the hinge point between them and the lifting slide rail, so that the grid blades change from a horizontal state to a downward deflection state. Step 3: Start the straightening motor to drive the lead screw to rotate. The rotational motion of the lead screw will be synchronously converted into the linear motion of the lead screw nut. The lead screw nut drives the force transmission plate to move down synchronously, which in turn drives the lifting sliding rail to move up along the guide stationary sliding rail. At the same time, it drives the grid blades to deflect around the hinge point between the grid blades and the transmission link until the grid blades return to the horizontal state from the downward deflection state. Step 4: Select a test point at the center of the test section of the wind tunnel, and install a hot wire probe at the selected test point. The distance between the test point and the grid blade should not be less than 10 times the chord length of the grid blade. Step 5: Start the wind tunnel and adjust the wind speed to the set value. Then, the hot wire probe at the test point will measure the airflow pulsation velocity in real time and convert the measured airflow pulsation velocity into airflow turbulence. Step 6: Start the flapping wing vibration actuator motor to drive the rotary disc to rotate. The rotary disc drives the transmission link to move up and down reciprocatingly through the force transmission rod, which in turn drives the grid blades to flap around the hinge point between the grid blades and the lifting slide rail. Step 7: Change the speed of the flapping wing vibration actuator motor to adjust the flapping wing vibration frequency of the grid blades, thereby changing the airflow pulsation speed and thus changing the airflow turbulence intensity until the measured airflow turbulence intensity matches the set target turbulence intensity. Step 8: Repeat steps 1 to 7, except that the wind speed setting remains unchanged, but the flapping amplitude setting and the target turbulence setting of the grid blades are changed. Step 9: Repeat steps 1 through 8, the difference being that you adjust the wind speed setting. Step 10: Establish a database of wind speed, grating blade flapping amplitude, grating blade flapping frequency, and target turbulence intensity; Step 11: When conducting wind tunnel tests, input the target turbulence intensity. Based on the changes in wind speed, automatically match the corresponding flapping amplitude and vibration frequency of the grid blades from the database, so that the airflow turbulence intensity in the wind tunnel is automatically adjusted to the target value.

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