A maglev train track beam for wind tunnel experiments and a wind tunnel experiment method

Abstract

The present invention provides a maglev train track beam for wind tunnel experiments, including a track beam body. A diversion cavity extending along the length direction is provided inside the track beam body. The diversion cavity connects the two ends of the track beam body and forms a channel for air flow to pass through. The present invention also provides a method for wind tunnel experiments using the above-mentioned maglev train track beam, including steps such as placing a maglev train model, arranging sensors on the track beam body, arranging sensors in the diversion cavity, arranging test instruments in the maglev train model, and starting the wind tunnel fan. The present invention can greatly reduce the turbulence generated at the front edge of the track beam during the experiment, without affecting the flow field around the train. At the same time, it reduces the length from the train head to the front edge of the track beam to reduce the thickness of the boundary layer, shortens the track beam cantilever, and greatly reduces jitter to improve the experimental measurement accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of wind tunnel experiments, and in particular relates to a maglev train track beam used for wind tunnel experiments and a wind tunnel experiment method. Background Art

[0002] In order to reduce the land acquisition area, the current high-speed railway adopts the method of replacing roads with bridges. Maglev trains run on track beams for most of the time. The length of the track beams is very long, and the wind tunnel test can only simulate the limited length of the track beams, and cannot simulate the relative movement of the train and the track beams. In addition, due to the large cross-section of the track beams, the front edge of the track beams will have a large disturbance to the flow field around the train. To avoid this interference, the distance from the front edge of the track beam to the head of the train needs to be relatively long. Generally, the height or width of the beam is used as the characteristic length, and this length needs to be 8 to 10 times the characteristic length. However, there are two defects when the length from the head of the train to the front edge of the track beam is too long: first, the thickness of the boundary layer on the track beam increases with the increase of length, and this boundary layer does not exist in the actual train operation process, but is caused by the wind tunnel test method. The thicker the thickness, the greater the impact on the results, and it should be eliminated or reduced as much as possible. Especially for the wind tunnel test of the maglev train, since the gap between the bottom and side of the track beam and the train is very small, the boundary layer quickly submerges the gap, seriously interfering with the bottom flow field, and causing large errors in the measurement results. Secondly, the turntable of the wind tunnel is of limited size. The front and rear of the track beam are cantilever supports. If the length is longer, the vibration will be more severe during the experiment. The vibration will produce vertical velocity in the airflow above the track beam, causing the flow field at the bottom of the vehicle to change, which will bring large errors to the measurement.

[0003] The existing maglev track beam used in wind tunnel experiments is a solid structure. In order to reduce the impact of the separation vortex generated at the leading edge of the track beam on the head of the train, Figures 1 to 3 It is a single-beveled guide structure track beam, and the front edge of the windward end of the track beam is provided with a unidirectional guide structure inclined at a certain angle. Figures 4 to 6 The track beam has a double-beveled guide structure, and the front edge of the windward end of the track beam adopts a two-way guide structure on the upper and lower surfaces. The front edges of the existing track beams are all treated with guides, but the turbulence generated by the front edges of the track beams will still have a certain impact on the head of the train. In addition, the length of the existing guide structure is relatively long, resulting in a long distance from the head of the train to the front edge of the track beam. The boundary layer will have a certain impact on the experimental results. At the same time, the longer guide structure leads to an increase in the cantilever support length, and the cantilever jitter will also affect the measurement results. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies existing in the prior art, and provide a maglev train track beam for wind tunnel experiments, which can significantly reduce the turbulence generated at the front edge of the track beam during experiments, will not affect the flow field around the train, and at the same time reduce the length from the train head to the front edge of the track beam, so as to reduce the thickness of the boundary layer, reduce the cantilever of the track beam, and significantly reduce jitter, thereby improving the experimental measurement accuracy.

[0005] To solve the above technical problem, the technical solution proposed by the present invention is as follows:

[0006] A maglev train track beam for wind tunnel experiments, including a track beam body, wherein a diversion cavity extending along the length direction is provided inside the track beam body, and the diversion cavity communicates the two ends of the track beam body and forms a channel for air flow to pass through. The track beam is designed as a hollow structure to form a diversion cavity, and air flow can pass through the diversion cavity, solving the problem in the prior art that when the air flow blows to the end section of the track beam due to the large cross-section of the track beam, large turbulence is generated, which causes large disturbance to the train flow field and leads to large errors in experimental results. At the same time, due to the reduction of disturbance, the distance between the train head and the front edge of the track beam can be greatly reduced, thereby significantly reducing the thickness of the boundary layer and improving the measurement accuracy of the experiment.

[0007] For the above-mentioned maglev train track beam for wind tunnel experiments, preferably, the windward end of the track beam body is a planar structure without protrusions. The windward end of the track beam body with this structure is planar, reducing the distance for setting a protruding diversion slope, so it is beneficial to reduce the thickness of the boundary layer and the jitter of the cantilever of the track beam body, and improve the accuracy and reliability of the wind tunnel experiment results.

[0008] For the above-mentioned maglev train track beam for wind tunnel experiments, preferably, the track beam body includes a top plate, side plates and a bottom plate, and the top plate, side plates and bottom plate enclose to form the track beam body with the diversion cavity. The top plate, side plates and bottom plate are used to enclose and form the track beam body with the diversion cavity to increase the area of the diversion cavity and reduce the disturbance caused by the windward end.

[0009] For the above-mentioned maglev train track beam for wind tunnel experiments, preferably, streamlined diversion structures are provided at the ends of the top plate, side plates and bottom plate along the thickness direction. The diversion structure includes an outer diversion surface and an inner diversion surface. The inner diversion surface is used to guide the air flow into the diversion cavity, and the outer diversion surface is used to guide the air flow out of the diversion cavity. Specifically, the diversion structure can be a wedge-shaped structure or a rounded corner structure. The diversion structure ensures that the air flow will not separate on the inner and outer surfaces of the track beam body. The air flow will not be diverted inside, so that the air flow can directly pass through the inside without blockage, avoiding the interference of the internal flow field on the external flow field. The air flow will not separate on the outer surface, which can avoid the interference of the air flow on the surroundings of the train.

[0010] In the above-mentioned maglev train track beam for wind tunnel experiment, preferably, the guide structure is a rounded structure provided at the ends of the top plate, side plate and bottom plate, and the outer guide surface and the inner guide surface are arranged symmetrically. Specifically, the ends of the top plate, side plate and bottom plate are chamfered to form a guide structure, the inner guide surface is the surface of the rounded structure on the side of the guide cavity, and the outer guide surface is the surface of the rounded structure facing outward. The outer guide surface and the inner guide surface have a smooth and continuous transition, and the dividing point between the two is located at the midpoint of the rounded arc, thereby forming a symmetrically arranged structure, that is, the radius of the rounded structure is half the thickness of the plate. The rounded structure is similar to the side of a semi-cylinder, which can ensure the guide effect of the front cross section of the track beam, better avoid the separation of the airflow on the inner and outer surfaces of the track beam body, so as to prevent the separated airflow from affecting the flow field in the guide cavity and outside the track beam body, further reduce the airflow interference around the train, and thus improve the experimental accuracy.

[0011] In the above-mentioned maglev train track beam for wind tunnel experiment, preferably, the thickness of the top plate, side plate and bottom plate is 5-10 mm. The thinner the plate material, the more conducive it is to alleviate or eliminate the flow separation at the front end of the track beam, and ensure that the airflow flows smoothly through the track beam guide cavity and the outer surface of the track beam.

[0012] The above-mentioned maglev train track beam used for wind tunnel experiments, preferably, is provided with a test area for parking the maglev train model, the starting point of the test area is at a distance M from the windward end face of the track beam body, 40mm≤M≤50mm. Since the thickness of the boundary layer on the track beam increases with the increase of length, the thicker the thickness, the greater the impact on the results, and it should be eliminated or reduced as much as possible, especially for the wind tunnel experiment of the maglev train, since the gap between the track beam and the bottom and side of the train is very small, the boundary layer quickly submerges the gap, seriously interfering with the bottom flow field, and causing large errors in the measurement results, so reasonable control of the distance M can effectively control the thickness of the boundary layer, thereby improving the accuracy of the experimental measurement.

[0013] The above-mentioned maglev train track beam used for wind tunnel experiments is preferably provided with a beam column for supporting the track beam at the bottom. The front and rear parts of the track beam body are cantilever supports. The longer the cantilever length, the more violent the vibration in the experiment. The vibration will generate vertical velocity for the airflow above the bridge deck, causing the flow field at the bottom of the train to change, which will bring large errors to the measurement. Reasonable control of the L value can effectively reduce the vibration, thereby reducing the error of the experimental measurement and improving the measurement accuracy.

[0014] As a general technical concept, the present invention also provides a method for conducting a wind tunnel test using the above-mentioned maglev train track beam, comprising the following steps:

[0015] S1. Place the maglev train model on the track beam body, and the distance between the front of the maglev train model and the end face of the windward end of the track beam body is M;

[0016] S2. Install a wind speed test sensor on the outside of the track beam body for testing the wind speed distribution outside the track beam body;

[0017] S3. Install a wind speed test sensor in the diversion cavity of the track beam body for testing the flow velocity distribution in the diversion cavity;

[0018] S4. Install test instruments in the maglev train model;

[0019] S5. Turn on the wind tunnel fan, start the test equipment and software, and start the experimental test work.

[0020] In the above wind tunnel experiment method, preferably, 40mm ≤ M ≤ 50mm in S1;

[0021] In S2, the wind speed test sensor is installed at 10mm, 20mm, 30mm, and 40mm away from the windward end of the track beam body;

[0022] In S3, the wind speed test sensor is installed at the centroid position of the cross-section of the track beam body, and at 10mm, 20mm, 30mm, and 40mm away from the windward end of the track beam body. In addition, wind speed test sensors are also installed at 1 / 3, 1 / 2, 2 / 3 of the length of the track beam body and at the outlet end;

[0023] The test instruments in S4 are a force measuring balance and a pressure scanning valve.

[0024] Due to the adoption of the track beam body with a hollow structure as described above in the wind tunnel experiment method of the present invention, the air flow can flow through the diversion cavity, reducing the influence of the front end face of the track beam body on the flow field of the track beam, and improving the measurement accuracy; the length from the train head to the end face of the windward end of the track beam body is very short, which can greatly reduce the thickness of the bridge boundary layer, and can also greatly reduce the length of the cantilever beams at the front and rear ends of the bridge, reducing the bridge vibration and the influence on the flow field at the bottom of the train, and further improving the measurement accuracy.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] The maglev train track beam for wind tunnel experiments of the present invention has a hollow structure for the track beam body, and the incoming air flow passes through the diversion cavity. Therefore, the influence of the front edge of the track beam on the flow field of the track beam surface is reduced from the decimeter scale in the prior art to the millimeter scale. Under the condition of reducing the influence of the front edge turbulence, the distance between the train head and the front edge of the track beam can be greatly reduced. Therefore, the thickness of the boundary layer on the upper surface of the track beam is greatly reduced, avoiding the influence of the boundary layer on the experimental results, and at the same time being beneficial to reducing the cantilever jitter and greatly improving the measurement accuracy of the wind tunnel experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a three-dimensional structure diagram of the track beam of the single bevel cutting type diversion structure for the existing maglev train wind tunnel test.

[0028] Figure 2 is a cross-sectional view of the track beam of the single bevel cutting type diversion structure for the existing maglev train wind tunnel test.

[0029] Figure 3 is a schematic diagram of the diversion effect of the track beam of the single bevel cutting type diversion structure for the existing maglev train wind tunnel test.

[0030] Figure 4 is a three-dimensional structure diagram of the track beam of the double bevel cutting surface diversion structure for the existing maglev train wind tunnel test.

[0031] Figure 5 is a cross-sectional view of the track beam of the double bevel cutting surface diversion structure for the existing maglev train wind tunnel test.

[0032] Figure 6 is a schematic diagram of the diversion effect of the track beam of the double bevel cutting surface diversion structure for the existing maglev train wind tunnel test.

[0033] Figure 7 is a three-dimensional structure diagram of the maglev train track beam for wind tunnel experiments of the present invention.

[0034] Figure 8 is Figure 7 a partial enlarged view of A in

[0035] Figure 9 is a cross-sectional view of the maglev train track beam for wind tunnel experiments of the present invention.

[0036] Figure 10 is Figure 9 a partial enlarged view of B in

[0037] Figure 11 is a longitudinal sectional view of the maglev train track beam for wind tunnel experiments of the present invention.

[0038] Figure 12 is Figure 11 a partial enlarged view of C in

[0039] Figure 13 It is a schematic diagram of the flow guiding effect of the maglev train track beam for wind tunnel experiments of the present invention.

[0040] 1. Track beam body; 11. Top plate; 12. Side plate; 13. Bottom plate; 14. Flow guiding structure; 141. Outer flow guiding surface; 142. Inner flow guiding surface; 2. Flow guiding cavity; 3. Beam column. Detailed implementation mode

[0041] For the convenience of understanding the present invention, the following will describe the present invention more comprehensively and meticulously in combination with the specification drawings and preferred embodiments, but the protection scope of the present invention is not limited to the following specific embodiments.

[0042] As Figures 7 to 13 shown, the maglev train track beam for wind tunnel experiments in this embodiment includes a track beam body 1. A flow guiding cavity 2 extending along the length direction is provided inside the track beam body 1. The flow guiding cavity 2 connects the two ends of the track beam body 1 and forms a channel for air flow to pass through. Since the air flow can pass through the flow guiding cavity 2, the track beam in this embodiment can reduce the influence of the front edge of the track beam body 1 on the flow field from the decimeter scale to the millimeter scale, thereby shortening the distance between the train head and the front edge of the track beam body 1 and reducing the influence of the boundary layer on the experimental results. The prior art takes the width of the track beam as the characteristic length. After 8 to 10 times the characteristic length, the influence of the front edge of the track beam body 1 is relatively small. At this time, the distance between the front edge of the track beam body 1 and the train head is 2.4 to 3.0 m (taking the model scale of 1:10 as an example). Even if the front edge of the track beam body 1 is streamlined, this distance also requires 1.5 to 2.0 meters; in this embodiment, a flow guiding cavity 2 is provided in the track beam body 1, and the air flow passes through the flow guiding cavity 2. The influence on the train flow field is the thickness of the track beam body 1, which is 5 mm, and its influence range is 8 to 10 times the characteristic length. The distance between the front edge of the track beam body 1 and the train head only needs to be 40 to 50 mm to effectively reduce the influence of the turbulent flow.

[0043] After reducing the distance between the front edge of the track beam body 1 and the train head, the thickness of the boundary layer on the upper surface of the track beam body 1 under the train head is significantly reduced. If the air density in the wind tunnel is 1.225 kg / m 3 , and the blowing wind speed is 60 m / s. In the prior art, when the distance x between the front edge of the track beam body 1 and the train head is 2.0 m, according to the calculation formula of the flat plate negative layer Assume that the front streamline of the track beam body 1 is perfectly streamlined and no boundary layer separation will occur. At this time, the thickness of the boundary layer on the upper surface of the track beam body 1 under the train head is 3.5 mm, and the distance between the bottom of the maglev train and the bridge is 18.75 mm. The boundary layer has blocked this gap; in this embodiment, the thickness of the boundary layer on the upper surface of the track beam body 1 under the train head is 0.55 mm. Therefore, the track beam of this embodiment greatly reduces the influence of the boundary layer on the experimental test accuracy.

[0044] In this embodiment, the windward end of the track beam body 1 is a flat structure without a protrusion. Specifically, the end faces at both ends of the track beam body 1 in this embodiment are both flat, and no inclined cut surface is provided to form a protrusion, reducing the length of the track beam body 1, which is beneficial to reducing the thickness of the boundary layer and the cantilever length, and improving the experimental test accuracy.

[0045] In this embodiment, the track beam body 1 includes a top plate 11, side plates 12, and a bottom plate 13. The top plate 11, side plates 12, and bottom plate 13 enclose to form a track beam body 1 with a flow guiding cavity 2. The thicknesses of the top plate 11, side plates 12, and bottom plate 13 are 5 mm. Specifically, the top plate 11 and the bottom plate 13 are both flat plates, and the top plate 11 and the bottom plate 13 are arranged in parallel. The width of the top plate 11 is greater than the width of the bottom plate 13. There are two side plates 12, and they are symmetrically arranged with respect to the axis of the track beam. The side plates 12 are made into a specific shape. The side plates 12 include a maglev track functional area and a bending area. The maglev track functional area is connected to the top plate through a vertical side. One end of the bending area is connected to the maglev track functional area, and the other end of the bending area is connected to the bottom plate 13. The bending area as a whole presents a concave shape. The two symmetrical side plates 12 are concave in the bending area to form a shape that is narrower at the top and wider at the bottom. This structure of the track beam body 1 can better cooperate with the flow guiding cavity 2, reduce the end air flow interference, and is beneficial to improving the experimental accuracy.

[0046] In this embodiment, streamlined flow guiding structures 14 are provided at the ends of the top plate 11, side plates 12, and bottom plate 13 along the thickness direction. The flow guiding structures 14 include an outer flow guiding surface 141 and an inner flow guiding surface 142. The inner flow guiding surface 142 is used to guide the air flow into the flow guiding cavity 2, and the outer flow guiding surface 141 is used to guide the air flow out of the flow guiding cavity 2. The flow guiding structures 14 are fillet structures provided at the ends of the top plate 11, side plates 12, and bottom plate 13, and the outer flow guiding surface 141 and the inner flow guiding surface 142 are symmetrically arranged. Specifically, the outer flow guiding surface 141 is on the outside, and the inner flow guiding surface 142 is on the inside. Fillets are formed at the windward end face of the track beam body 1 to form the flow guiding structures 14, and the fillet radius is half of the plate thickness. As Figure 13As shown, the flow field reaches the front end of the track beam from the far end. Since the plate structure constituting the track beam body 1 is only 5 mm thick, and the front end of each plate adopts an arc-shaped rounded flow guide structure 14, the flow separation phenomenon caused by the square structure at the front end of the wall (if the rounded structure is not adopted, when the airflow blows to the end without the rounded structure, part of the flow field will rise and part will flow downward), that is, when the flow field flows through the streamlined flow guide structure 14, it will smoothly enter the external space and the inside of the flow guide cavity 2 of the track beam along the upper and lower guide surfaces. The flow guide structure 14 greatly weakens the interference of the structural parameters and appearance of the track beam itself on the flow field, thereby ensuring the authenticity and accuracy of the flow field structure acting on the train.

[0047] In this embodiment, a test area for parking a maglev train model is provided on the track beam, and the distance between the starting point of the test area and the windward end face of the track beam body 1 is M, 40mm≤M≤50mm. In this embodiment, a beam column 3 for supporting the track beam is provided at the bottom of the track beam, and the distance L between the beam column 3 and the end of the track beam body 1 is 0.2m. The turntable scale of the wind tunnel is limited, and generally only the beam column 3 is allowed to be set within the internal range of the turntable. Otherwise, the track beam cannot be tested for crosswind at an angle. Therefore, the distance between the beam column 3 and the end of the track beam body 1 belongs to cantilever support. The longer the cantilever length, the more violent the shaking in the experiment. The shaking will generate vertical velocity for the airflow above the bridge deck, causing the flow field at the bottom of the vehicle to change, which will bring a large error to the measurement. Taking the model ratio of the prior art as 1:10 as an example, its cantilever is about 1.5 to 2.0 meters longer than that of the present embodiment. Therefore, the rigidity of the track beam body 1 must be very large to reduce the shaking, and increasing the rigidity of the track beam body 1 will greatly increase the manufacturing, transportation and installation costs. In the track beam of this embodiment, the front edge of the track beam body 1 is short from the head of the train, and there is no need to set a protruding inclined guide, so the overall length and cantilever length of the track beam are shortened, which can greatly reduce the jitter of the track beam and reduce the manufacturing, transportation and installation costs.

[0048] The wind tunnel test method of the maglev train of this embodiment uses the above-mentioned maglev train track beam to conduct the test, and includes the following steps:

[0049] S1. Place the maglev train model on the track beam body 1. The distance between the front of the maglev train model and the windward end surface of the track beam body 1 is M, where 40 mm ≤ M ≤ 50 mm;

[0050] S2. A wind speed test sensor for testing the wind speed distribution outside the track beam body 1 is arranged on the outer side of the track beam body 1. Specifically, a wind speed test sensor is arranged at 10 mm, 20 mm, 30 mm, and 40 mm behind the windward end of the track beam. The sensor is used to test the wind speed distribution outside the track beam cavity, and then analyze and obtain the boundary layer parameters between the front end of the train and the front end of the track beam;

[0051] S3. Install a wind speed test sensor in the diversion cavity 2 of the track beam body 1 for testing the flow velocity distribution in the diversion cavity 2. Specifically, install wind speed sensors at the centroid position of the cross-section of the track beam body 1 along the cavity direction at the same positions as in S2. In addition, install wind speed sensors at the 1 / 3, 1 / 2, 2 / 3 of the track beam length and the outlet position to test the flow velocity distribution in the track beam cavity, so as to analyze and obtain the overall diversion effect of the cavity-type track beam;

[0052] S4. Install test instruments in the maglev train model, specifically test instruments such as a force measuring balance and a pressure scanning valve;

[0053] S5. Turn on the wind tunnel fan, start the test equipment and software, and start the experimental test work.

[0054] Using the wind tunnel experiment method of this embodiment to test the maglev train model can obtain accurate test results with small experimental errors.

[0055] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent embodiment with equivalent changes, without departing from the scope of the technical solution of the present invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of the protection of the technical solution of the present invention.

Claims

1. A maglev train track beam for wind tunnel experiments, characterized in that: It includes a track beam body (1), and a diversion cavity (2) extending along the length direction is provided inside the track beam body (1). The diversion cavity (2) connects the two ends of the track beam body (1) and forms a channel for air flow to pass through. The windward end of the track beam body (1) is a flat structure without protrusions. A test area for parking a maglev train model is provided on the track beam. The distance from the starting point of the test area to the windward end face of the track beam body (1) is M, and 40 mm ≤ M ≤ 50 mm.

2. The maglev train track beam for wind tunnel experiment according to claim 1, characterized in that: The track beam body (1) includes a top plate (11), side plates (12), and a bottom plate (13). The top plate (11), side plates (12), and bottom plate (13) enclose to form the track beam body (1) having the diversion cavity (2).

3. The maglev train track beam for wind tunnel experiments according to claim 2, characterized in that: Streamlined diversion structures (14) are provided at the ends of the top plate (11), side plates (12), and bottom plate (13) along the thickness direction. The diversion structure (14) includes an outer diversion surface (141) and an inner diversion surface (142). The inner diversion surface (142) is used to guide the air flow into the diversion cavity (2), and the outer diversion surface (141) is used to guide the air flow out of the diversion cavity (2).

4. The maglev train track beam for wind tunnel experiments according to claim 3, characterized in that: The diversion structure (14) is a rounded corner structure provided at the ends of the top plate (11), side plates (12), and bottom plate (13), and the outer diversion surface (141) and the inner diversion surface (142) are symmetrically arranged.

5. The maglev train track beam for wind tunnel experiments according to any one of claims 1 to 4, characterized in that: The thickness of the top plate (11), side plates (12), and bottom plate (13) is 5 - 10 mm.

6. The maglev train track beam for wind tunnel experiment according to any one of claims 1 to 4, characterized in that: A beam column (3) for supporting the track beam is provided at the bottom of the track beam.

7. A wind tunnel experiment method for a maglev train, characterized in that: Performing an experiment using the maglev train track beam according to any one of claims 1 to 6 includes the following steps. S1. Place the maglev train model on the track beam body (1), and the distance between the head of the maglev train model and the windward end face of the track beam body (1) is M. S2. Install wind speed test sensors on the outside of the track beam body (1) for testing the wind speed distribution outside the track beam body (1). S3. Install wind speed test sensors in the diversion cavity (2) of the track beam body (1) for testing the flow field velocity distribution in the diversion cavity (2). S4. Install test instruments in the maglev train model. S5. Turn on the wind tunnel fan, start the test equipment and software, and start the experimental test work.

8. The wind tunnel experiment method according to claim 7, wherein: In S1, 40 mm ≤ M ≤ 50 mm; In S2, the wind speed test sensors are installed at 10 mm, 20 mm, 30 mm, and 40 mm away from the windward end of the track beam body (1). In S3, the wind speed test sensors are installed at the centroid position of the cross-section of the track beam body (1), and are also at 10 mm, 20 mm, 30 mm, and 40 mm away from the windward end of the track beam body (1). In addition, wind speed test sensors are also provided at 1 / 3, 1 / 2, 2 / 3 of the length of the track beam body (1) and at the outlet end. The test instrument in S4 is a force measuring balance and a pressure scanning valve.

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