Elastic wedge device and design method thereof

Abstract

The application discloses an elastic wedge device and a design method thereof, wherein the elastic wedge device comprises a base, a stand column is fixedly installed on the base, a plurality of movable plates are sleeved on the stand column, the movable plates are connected with the stand column through torsion components, and torsional vibration can occur in the movable plates. When the wind tunnel flow wind blows through the wedge, the movable plates will occur torsional vibration under the action of the torsion components, the direct current wind disturbance is intensified, and a more complex turbulent flow field is generated. In the device, strong turbulent flow can also be generated in the upper part, and the problem that turbulent flow rapidly decays along the height direction, i.e., from bottom to top, is solved. Compared with the wedge provided with a large number of fixed baffles to increase turbulent flow, the influence of the movable plates on the flow field is smaller, too many interferences are not introduced, and the debugging of the wind field is favorable.

Description

Technical Field

[0001] This invention relates to the field of wind tunnel testing technology, and in particular to an elastic wedge device and its design method. Background Technology

[0002] In recent years, a large number of long-span bridges have emerged in high-altitude, deeply incised canyon areas. Because these areas are prone to large-angle wind flows, the wind-induced dynamic response stability of long-span suspension bridges becomes particularly critical. Existing research mainly focuses on long-span bridges in coastal and plain areas, where wind conditions differ significantly from those in mountainous canyons. There is a lack of research on the characteristics of non-uniform flow and high angle-of-attack wind fields in high-altitude canyon areas, thus necessitating further research.

[0003] Wind tunnel testing is one of the most important research methods for analyzing the dynamic stability of bridges both domestically and internationally. It allows for direct observation of the entire testing process and enables the control, modification, and repetition of test conditions to obtain the phenomena desired by bridge engineers. However, natural winds within the atmospheric boundary layer exhibit strong randomness in both time and space. Therefore, in addition to satisfying geometric similarity, wind tunnel tests must accurately simulate the wind field characteristics of the atmospheric boundary layer at the bridge site. Currently, wind tunnel testing methods for simulating the atmospheric boundary layer are mainly divided into passive simulation methods and active simulation methods. Among these, the triangular wedge method is currently the most widely used passive simulation method.

[0004] Triangular spires can easily simulate the average wind speed profile of different terrains by changing the shape of the wedge, and the turbulence intensity in the middle and lower parts can be easily increased by changing the bottom width. However, the turbulence attenuates too quickly along the height, resulting in insufficient turbulence intensity in the upper and middle parts, failing to meet requirements, thus lacking in turbulence profile simulation. For example, Chinese utility model patent CN205138754U discloses increasing near-surface turbulence intensity by setting baffles. Adding baffles can significantly increase turbulence intensity, but as the number and width of the baffles increase, the wind field is greatly affected, posing significant difficulties for flow field adjustment. Therefore, currently, bottom baffles are generally used to appropriately increase the overall turbulence intensity. Although using some irregularly shaped wedges can improve the situation, it still cannot fundamentally and well simulate the complex turbulent wind field of deeply incised canyons. Summary of the Invention

[0005] The purpose of this invention is to overcome the problem that the turbulence intensity in the upper part of the existing wedges used for wind tunnel testing is too low, which makes it difficult to simulate the turbulence profile and fails to meet the requirements of wind tunnel testing. This invention provides an elastic wedge device and its design method.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] An elastic wedge device includes a base, on which a column is fixedly mounted. The column is fitted with a plurality of movable plates, which are connected to the column via a torsion member and are capable of torsional vibration.

[0008] The elastic wedge device provided by this invention can effectively simulate the turbulent wind field in a deep canyon region. This device, through the arrangement of multiple movable plates, causes vortex shedding of the movable plates when the incoming wind blows over the wedge. Consequently, the movable plates undergo torsional vibration under the action of the torsional components. This torsional vibration exacerbates the direct current wind disturbance, generating a more complex turbulent wind field. This device can generate complex turbulent wind fields not only in the middle and lower parts, but also in the upper part, where movable plates are also installed. Therefore, strong turbulence can be generated in the upper middle section as well, solving the problem of rapid attenuation of turbulence along the height direction (i.e., from bottom to top). Thus, a better simulation effect can be obtained for the entire turbulence intensity profile. Compared with wedges that use numerous fixed baffles to increase turbulence, the movable plates have less impact on the flow field, introducing less interference and facilitating wind field adjustment.

[0009] Optionally, the elastic wedge device further includes multiple fixed plates, which are fixedly connected to the column. The fixed plates and the movable plates are alternately arranged along the height direction, and the blocking ratio of the fixed plates decreases along the height.

[0010] The elastic wedge device provided by this invention, with its alternating fixed and movable plates, can create complex airflow blocking patterns, further enhancing airflow turbulence. When the number of measuring points is small, such as ≤3, the combined effect of the fixed and movable plates generates eddies and turbulence of various scales, providing a richer airflow environment for sampling and resulting in better simulation effects. The blocking ratio of the fixed plate decreases along the height direction, i.e., from bottom to top, producing an approximately linear wind speed profile that more closely resembles the actual conditions in canyon areas.

[0011] Optionally, the vibration frequency f of the movable plate i satisfy:

[0012]

[0013] In the formula: f i The vibration frequency of the i-th active plate, in Hz;

[0014] m i The mass of the i-th active plate is expressed in kg.

[0015] k i Let be the stiffness of the i-th torsional component, in N / m.

[0016] Optionally, the resilient wedge device is formed in a trapezoidal or triangular shape from bottom to top.

[0017] Optionally, the torsion component is a torsion spring.

[0018] Optionally, the projection of the movable plate onto the horizontal plane is T-shaped.

[0019] Optionally, the projections of both the movable plate and the fixed plate onto the horizontal plane are T-shaped.

[0020] A method for designing an elastic wedge device, comprising the following steps:

[0021] S1. Select 1, 2...i observation points along the height direction, with the heights of the i observation points above the ground being H1, H2...H... i Collect wind load data at each observation point and determine the central principal frequencies F1, F2…F at each observation point. i ;

[0022] S2. Based on the wind tunnel test scaling ratio of 1:u, calculate the height h of each observation point above the ground under the scaling condition. i :

[0023]

[0024] In the formula, H i The height of the i-th measured observation point, in meters;

[0025] h i The height of the i-th measured observation point after scaling, in meters;

[0026] Obtain the mass of each of the movable plates, and calculate the stiffness of the i-th torsion component according to the following formula:

[0027]

[0028] In the formula: F i Let be the central dominant frequency of the wind load at the i-th observation point, in Hz;

[0029] m i The mass of the i-th active plate is expressed in kg.

[0030] k i Let be the stiffness of the i-th torsional component, in N / m.

[0031] The elastic wedge device design method provided by this invention can easily design the stiffness of the torsional component by obtaining the central dominant frequency of the wind load at the corresponding observation point and the mass of the movable plate. By utilizing the geometric similarity principle of wind tunnel testing and matching conversion through scaling ratio, the height of the measured point from the ground after scaling can be quickly determined. It requires fewer parameters, is simple and practical, and is easy to use in engineering.

[0032] Optionally, the mass of the movable plate is calculated based on the density and volume of the movable plate.

[0033] Optionally, the central principal frequency of the wind load at the i-th observation point is the same as the vibration frequency of the i-th movable plate.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] 1. The elastic wedge device provided by this invention can effectively simulate the turbulent wind field in a deep canyon area. This device, by setting multiple movable plates, causes vortex shedding of the movable plates when the incoming wind blows over the wedge. Consequently, the movable plates undergo torsional vibration under the action of the torsional components. This torsional vibration intensifies the direct current wind disturbance, thus generating a more complex turbulent wind field. This device can generate complex turbulent wind fields not only in the middle and lower parts, but also in the upper part, where movable plates are also installed. Therefore, strong turbulence can be generated in the upper middle part as well, solving the problem of rapid attenuation of turbulence along the height direction (i.e., from bottom to top), thus achieving a better simulation effect across the entire turbulence profile. Compared with wedges that use numerous fixed baffles to increase turbulence, the movable plates have less impact on the flow field, do not introduce excessive interference, and are beneficial for wind field adjustment.

[0036] 2. The elastic wedge device provided by this invention, with its alternating fixed and movable plates, can form complex airflow blocking patterns, further enhancing airflow turbulence. When the number of measuring points is small, for example, ≤3, the combined effect of the fixed and movable plates will generate eddies and turbulence of various scales, providing a richer airflow environment for sampling and resulting in better simulation effects. The blocking ratio of the fixed plate decreases along the height direction, i.e., from bottom to top, producing an approximately linear wind speed profile that more closely resembles the actual conditions in canyon areas.

[0037] 3. The elastic wedge device design method provided by the present invention can conveniently design the stiffness of the torsional component by obtaining the central dominant frequency of the wind load at the corresponding observation point and the mass of the movable plate. By utilizing the geometric similarity principle of wind tunnel testing and matching conversion through scaling ratio, the height of the measured point from the ground after scaling can be quickly determined. It requires fewer parameters, is simple and practical, and is easy to use in engineering. Attached Figure Description

[0038] Figure 1 A schematic diagram of the elastic wedge device provided in Example 1;

[0039] Figure 2 for Figure 1 The main view;

[0040] Figure 3 for Figure 1 Side view;

[0041] Figure 4 This is a schematic diagram showing the column being installed on the base.

[0042] Figure 5 This is a schematic diagram of the elastic wedge device provided in Example 2;

[0043] Figure 6 This is a schematic diagram of the elastic wedge device provided in Example 3;

[0044] Figures 7a1 to 7a6 This is a graph showing the wind load data at six measured points in Example 5;

[0045] Figures 7b1 to 7b6 The Davenport power spectrum at six measured points in Example 5;

[0046] Figures 8a1 to 8a3 This is a graph showing the wind load data at three measured points in Example 6;

[0047] Figures 8b1 to 8b3 The Davenport power spectrum is shown at three measured points in Example 6.

[0048] Reference numerals: 1-base, 2-column, 3-movable plate, 4-torsion component, 5-fixed plate. Detailed Implementation

[0049] The present invention will be further described in detail below with reference to experimental examples and specific embodiments. However, this should not be construed as limiting the scope of the above-mentioned subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0050] Example 1

[0051] A resilient wedge device, such as Figure 1-4 As shown, the wedge includes a triangular base 1, which is typically fixed to the ground with bolts. A column 2 is fixedly installed on the base 1, and the column 2 can be set perpendicular to the base 1 so that the wedge will not tip over or collapse when the incoming airflow blows over it.

[0052] Multiple movable plates 3 are fitted onto the outer surface of the column 2, such as Figure 1 As shown, the column 2 is fitted with six movable plates 3. To facilitate the rotation of the movable plates 3 around the column 2, the movable plates 3 can be connected to the column 2 via rotating bearings, allowing for easier rotation. To enable torsional vibration of the movable plates 3, they are also connected to the column 2 via a torsion component 4, specifically a torsion spring. Figure 1-3 As shown, the projection of the movable plate 3 onto the horizontal plane is T-shaped; that is, when the base 1 is installed on the ground, the orthographic projection of the movable plate 3 onto the base 1 is T-shaped. Figure 2As shown, the front view of the elastic wedge device provided in this embodiment forms a trapezoid or triangle from bottom to top. That is, in the elastic wedge device of this embodiment, the horizontal length of the movable plate 3 gradually shortens from bottom to top.

[0053] In this embodiment, the vibration frequency f of the movable plate 3 is... i satisfy:

[0054]

[0055] In the formula: f i Let be the vibration frequency of the i-th moving plate 3, in Hz;

[0056] m i Let 3 be the mass of the i-th movable plate, in kg;

[0057] k i Let be the stiffness of the i-th torsional component 4, in N / m.

[0058] The elastic wedge device provided by this invention can effectively simulate the turbulent wind field in a deep canyon area. This device uses multiple movable plates 3. When the incoming wind blows over the wedge, the movable plates 3 experience vortex shedding under the influence of the wind. Therefore, the movable plates 3 undergo torsional vibration under the action of the torsional component 4. This torsional vibration of the movable plates 3 intensifies the direct current wind disturbance, thus generating a more complex turbulent wind field. This device can generate complex turbulent wind fields not only in the middle and lower parts, but also in the upper part, where movable plates 3 are also installed. Therefore, strong turbulence can be generated in the upper middle part as well, solving the problem of rapid attenuation of turbulence along the height direction (i.e., from bottom to top). Thus, the entire turbulence profile can be simulated effectively. Compared with wedges that use numerous fixed baffles to increase turbulence, the movable plates 3 have less impact on the flow field and do not introduce excessive interference, which is beneficial for wind field adjustment.

[0059] Example 2

[0060] Based on Embodiment 1, the elastic wedge device provided in this embodiment further includes multiple fixing plates 5, which are fixedly connected to the column 2. Figure 5 As shown, the elastic wedge device consists of a fixed plate 5 and a movable plate 3 arranged alternately from bottom to top, and the blocking ratio of the fixed plate 5 decreases along the height direction, i.e., from bottom to top. Figure 5 As shown, the front view of the elastic wedge device in this embodiment also forms a trapezoid or triangle from bottom to top. The vibration frequency f of the movable plate 3 in this embodiment... i Also satisfies:

[0061]

[0062] The elastic wedge device provided by this invention, with the fixed plate 5 and the movable plate 3 alternately arranged, can form a complex airflow blocking mode, further improving the turbulence of the airflow. When there are fewer measuring points, for example, when the number of measuring points is ≤3, the combined effect of the fixed plate 5 and the movable plate 3 will form eddies and turbulence of various scales, providing a richer airflow environment for sampling and better simulation effect.

[0063] When the incoming wind from the wind tunnel blows over the wedge, the wedge generates vortices by separating the flow through its fixed plate 5. The width of the fixed plate 5 determines the size of the vortex and the intensity of the turbulent fluctuations. The blocking ratio of the fixed plate 5 decreases along the height direction, i.e. from bottom to top, which can produce an approximately linear wind speed profile that is closer to the actual situation in the canyon area.

[0064] Example 3

[0065] Based on Embodiment 1, the elastic wedge device provided in this embodiment further includes multiple fixing plates 5, which are fixedly connected to the column 2. Figure 6 As shown, the elastic wedge device consists of a movable plate 3 and a fixed plate 5 arranged alternately from bottom to top, and the blocking ratio of the fixed plate 5 decreases along the height direction, i.e., from bottom to top. Figure 6 As shown, the front view of the elastic wedge device in this embodiment also forms a trapezoid or triangle from bottom to top. The vibration frequency f of the movable plate 3 in this embodiment... i Also satisfies:

[0066]

[0067] Example 4

[0068] The present invention also provides a design method for an elastic wedge device, which is used to design the elastic wedge devices provided in embodiments 1-3, and specifically includes the following steps:

[0069] S1. Based on the actual measured location, select 1, 2...i observation points along the height direction. The heights of the i measured observation points from the ground are H1, H2...H... i Wind load data were collected at each observation point using wind speed testing equipment. By processing the measured wind load data, the central dominant frequencies F1, F2…F6 of the wind load at each observation point were determined. i Generally, the central principal frequency of the wind load at the i-th observation point is the same as the vibration frequency of the i-th movable plate 3, i.e., F i =f i .

[0070] Specifically, common anemometers such as ultrasonic anemometers and laser anemometers can be used for wind speed testing to ensure coverage of all predetermined observation points.

[0071] S2. Based on the wind tunnel test scaling ratio of 1:u, calculate the height h of each observation point above the ground under the scaling condition. i :

[0072]

[0073] In the formula, H i The height of the i-th measured observation point, in meters;

[0074] h i The height of the i-th measured observation point after scaling down is expressed in meters (m).

[0075] The mass of each movable board 3 is obtained. For example, when the movable board 3 is made of wood, the mass of each movable board 3 can be determined in advance based on the density of the wood and the size of the movable board 3.

[0076] The stiffness of the i-th torsional component 4 is calculated using the following formula:

[0077]

[0078] In the formula: F i Let be the central dominant frequency of the wind load at the i-th observation point, in Hz;

[0079] m i Let 3 be the mass of the i-th movable plate, in kg;

[0080] k i Let be the stiffness of the i-th torsional component 4, in N / m.

[0081] The vertical height of the center of gravity of each movable plate 3 from the ground corresponds to the scaled height of the measured observation point. This allows for the convenient design of the height of each movable plate 3 and the stiffness of the corresponding torsional component 4. The elastic wedge device design method provided by this invention can conveniently design the stiffness of the torsional component 4 by obtaining the central dominant frequency of the wind load at the corresponding observation point and the mass of the movable plate 3. Utilizing the geometric similarity principle of wind tunnel testing, the height of the measured point from the ground after scaling can be quickly determined through matching conversion using the scaling ratio. It requires fewer parameters, is simple and practical, and is easy to use in engineering.

[0082] Example 5

[0083] This embodiment takes an actual bridge as the research background and designs the elastic wedge device of the fully movable plate 3 structure in Embodiment 1.

[0084] First, based on the location of the bridge, six measurement points were set up along the vertical direction (measurement point 1, i.e., i=1; measurement point 2, i.e., i=2; measurement point 3, i.e., i=3; measurement point 4, i.e., i=4; measurement point 5, i.e., i=5; and measurement point 6, i.e., i=6). The heights of the six measurement points above the ground were H1=15m, H2=30m, H3=45m, H4=60m, H5=75m, and H6=90m, respectively. Wind load velocity time histories were collected at the six measurement points using wind speed testing equipment. Figures 7a1 to 7a6 The wind load data from six measured points are displayed sequentially. Based on the measured wind load data, the Davenport power spectrum of the six measured points is calculated, as follows: Figures 7b1 to 7b6 The Davenport power spectra at six measured points are presented sequentially. The frequency corresponding to the maximum value of the Davenport power spectrum is the dominant frequency of the wind load, which is the central principal frequency of the wind load at the corresponding observation point. The dominant frequencies of the six measured points are shown in Table 1.

[0085] Table 1. Wind load information at measured points in Example 5.

[0086] Measured point 1 Measured point 2 Measured point 3 Measured point 4 Measured point 5 6 measured points Height (m) 15 30 45 60 75 90 Excellent frequency (Hz) 0.0100 0.019 0.029 0.039 0.048 0.058

[0087] Based on the existing wind tunnel dimensions, the scaling ratio 1:u is determined to be 1:50, according to the following formula:

[0088]

[0089] The measured heights above the ground at the scaled-down locations are h1 = 0.3m, h2 = 0.6m, h3 = 0.9m, h4 = 1.2m, h5 = 1.5m, and h6 = 1.8m. Due to the large number of measured points, the elastic wedge was used... Figure 1 The design of the fully movable board 3 structure shown refers to the design of six movable boards 3 corresponding to the measuring points. The mass of each movable board 3, including the elastic wedges, can be determined in advance based on the density and dimensions of the wooden movable board 3, and then calculated according to the following formula:

[0090]

[0091] The stiffness of each torsion spring 4 is determined. The parameters of the elastic wedge design in this embodiment are shown in Table 2. The height of the center of gravity of each movable plate 3 from the ground corresponds to the height of the measured point from the ground after scaling.

[0092] Table 2 Design parameters of the elastic wedge device in Example 5 Example 5

[0093] Measured point 1 Measured point 2 Measured point 3 Measured point 4 Measured point 5 6 measured points Center of gravity height (m) 0.3 0.6 0.9 1.2 1.5 1.8 Mass (kg) 5.5 4.5 3.5 2.5 1.5 0.5 Torsion spring stiffness (N / m) 0.022 0.063 0.117 0.149 0.135 0.067

[0094] Example 6

[0095] This embodiment takes an actual bridge as the research background and designs an elastic wedge device with an alternating structure of movable plate 3 and fixed plate 5 in embodiment 2 or 3.

[0096] First, based on the location of the bridge, three measurement points were set up along the vertical direction (measurement point 1, i.e., i=1; measurement point 2, i.e., i=2; and measurement point 3, i.e., i=3). The heights of the three measurement points from the ground were H1=30m, H2=60m, and H3=90m, respectively. Wind load velocity time histories were collected at the three measurement points using wind speed testing equipment. Details are as follows... Figures 8a1 to 8a3 The wind load data from three measured points are displayed sequentially. Based on the measured wind load data, the Davenport power spectrum at the three measured points is calculated, as follows: Figures 8b1 to 8b3 The Davenport power spectra at three measured points are presented sequentially. The frequency corresponding to the maximum value of the Davenport power spectrum is the dominant frequency of the wind load, which is the central principal frequency of the wind load at the corresponding observation point. The dominant frequencies of the three measured points are shown in Table 3.

[0097] Table 3 Wind load information at measured points in Example 6 Example 3

[0098] Measured point 1 Measured point 2 Measured point 3 Height (m) 30 60 90 Excellent frequency (Hz) 0.016 0.042 0.052

[0099] Based on the existing wind tunnel dimensions, the scaling ratio 1:u is determined to be 1:50, according to the following formula:

[0100]

[0101] The measured heights above the ground at the scaled-down locations are h1 = 0.6m, h2 = 1.2m, and h3 = 1.8m. Since the number of measured points is small (i ≤ 3), the elastic wedge is used... Figure 5 or Figure 6 The design shown depicts an alternating arrangement of movable plates 3 and fixed plates 5, meaning three movable plates 3 correspond to each measuring point. The mass of each movable plate 3 can be predetermined based on the density and dimensions of the wooden movable plate 3, and then calculated according to the following formula:

[0102]

[0103] The stiffness of each torsion spring 4 is determined. The parameters of the elastic wedge design in this embodiment are shown in Table 4. The height of the center of gravity of each movable plate 3 from the ground corresponds to the height of the measured point from the ground after scaling.

[0104] Table 4. Design parameters of the elastic wedge device in Example 5.

[0105] Measured point 1 Measured point 2 Measured point 3 Center of gravity height (m) 0.6 1.2 1.8 Mass (kg) 5.5 3.5 1.5 Torsion spring stiffness (N / m) 0.056 0.243 0.160

[0106] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A design method for an elastic wedge device, characterized in that, Used to design an elastic wedge device The elastic wedge device includes a base (1), on which a column (2) is fixedly installed. The column (2) is fitted with a plurality of movable plates (3). The movable plates (3) are connected to the column (2) through a torsion component (4). The movable plates (3) are capable of torsional vibration. The design method for the elastic wedge device includes the following steps: S1. Select 1, 2...i observation points along the height direction, with the heights of the i observation points above the ground being H1, H2...H... i Collect wind load data at each observation point and determine the central principal frequencies F1, F2…F at each observation point. i ; S2. Based on the wind tunnel test scaling ratio of 1:u, calculate the height h of each observation point above the ground under the scaling condition. i : In the formula, H i The height of the i-th measured observation point, in meters; h i The height of the i-th measured observation point after scaling, in meters; Obtain the mass of each of the movable plates (3), and calculate the stiffness of the i-th torsion member (4) according to the following formula: In the formula: F i Let be the central dominant frequency of the wind load at the i-th observation point, in Hz; m i The mass of the i-th active plate (3) is expressed in kg. k i The stiffness of the i-th torsion member (4) is expressed in N / m.

2. The design method of the elastic wedge device according to claim 1, characterized in that, It also includes multiple fixed plates (5), which are fixedly connected to the column (2). The fixed plates (5) and the movable plates (3) are alternately arranged along the height direction, and the blocking ratio of the fixed plates (5) decreases along the height.

3. A design method for an elastic wedge device according to claim 1 or 2, characterized in that, The vibration frequency f of the movable plate (3) i satisfy: In the formula: f i The vibration frequency of the i-th active plate (3) is expressed in Hz. m i The mass of the i-th active plate (3) is expressed in kg. k i The stiffness of the i-th torsion member (4) is expressed in N / m.

4. A design method for an elastic wedge device according to claim 1 or 2, characterized in that, The elastic wedge device forms a trapezoid or triangle from bottom to top.

5. The design method of an elastic wedge device according to claim 1, characterized in that, The torsion component (4) is a torsion spring.

6. The design method of the elastic wedge device according to claim 1, characterized in that, The projection of the movable plate (3) onto the horizontal plane is T-shaped.

7. The design method of an elastic wedge device according to claim 2, characterized in that, The projections of the movable plate (3) and the fixed plate (5) onto the horizontal plane are both T-shaped.

8. The design method of an elastic wedge device according to claim 1, characterized in that, The mass of the movable plate (3) is calculated based on the density and volume of the movable plate (3).

9. The design method of an elastic wedge device according to claim 1, characterized in that, The central dominant frequency of the wind load at the i-th observation point is the same as the vibration frequency of the i-th movable plate (3).

Images