A segmented model system for wind tunnel testing

Abstract

This invention relates to the field of wind tunnel testing technology, and particularly to a segmental model system for wind tunnel testing, comprising: two sets of inner elastic suspension systems, with a segmental model connected between the inner elastic suspension systems; an outer elastic suspension system is also provided on the outside of each set of inner elastic suspension systems; the inner elastic suspension systems are capable of torsion relative to the outer elastic suspension systems and driving the outer elastic suspension systems to move vertically; a vertical damping adjustment device is disposed at both ends of the outer elastic suspension systems to provide adjustable vertical damping for the outer elastic suspension systems; a torsional damping adjustment device is disposed between the inner and outer elastic suspension systems to provide adjustable torsional damping for the inner elastic suspension systems; an end connection device for connecting the inner and outer elastic suspension systems; and a limiting device for restricting the vertical movement of the outer elastic suspension systems, realizing the separation and combination of vertical and torsional modes, as well as independent adjustment of vertical and torsional damping.

Description

Technical Field

[0001] This invention relates to the field of wind tunnel testing technology, and in particular to a segmental model system for wind tunnel testing. Background Technology

[0002] In recent years, with the continuous increase in the main span, bridge structural systems have become lighter and more flexible, with lower natural frequencies and reduced structural damping. This has significantly increased their sensitivity to wind loads, making wind-induced vibration problems such as flutter and vortex-induced vibration of the main girder increasingly prominent. To ensure the structural safety and normal use of bridges during construction and operation, wind resistance studies are typically conducted during the design phase.

[0003] Bridge flutter primarily manifests as structural failure dominated by torsional mode instability of the main girder, with vertical mode involvement being a key factor in its occurrence. Unlike flutter-induced structural instability, vortex-induced vibration of the bridge main girder mainly exhibits limited-amplitude motion under first- or multiple main girder modes. While its direct damage to the structural system is relatively minor, it can potentially lead to structural fatigue. Furthermore, vortex-induced vibration can affect visibility and ride comfort, thus adversely impacting the normal operation of the bridge.

[0004] Currently, segmental model wind tunnel testing is the main method for studying the vortex-induced vibration and flutter performance of bridge main girders. However, traditional segmental model systems cannot achieve direct separation of vertical and torsional modes, nor can they independently adjust vertical and torsional damping. Therefore, traditional segmental model systems are difficult to meet the requirements for studying the vertical and torsional vortex-induced vibration mode interference and flutter performance of main girders under the influence of damping and other factors. Summary of the Invention

[0005] The purpose of this invention is to address the problem that traditional segmental model systems in the background art cannot achieve direct separation of vertical and torsional modes, nor can they independently adjust vertical and torsional damping, and to provide a segmental model system for wind tunnel testing.

[0006] This invention provides a segmental model system for wind tunnel testing, comprising:

[0007] Two sets of opposing internal elastic suspension systems are connected by a segment model. Each set of internal elastic suspension systems is also provided with an external elastic suspension system on its outer side. The internal elastic suspension system can twist relative to the external elastic suspension system and drive the external elastic suspension system to move vertically.

[0008] A vertical damping adjustment device is installed at both ends of the external elastic suspension system to provide adjustable vertical damping for the external elastic suspension system;

[0009] A torsional damping adjustment device is disposed between the inner elastic suspension system and the outer elastic suspension system, for providing adjustable torsional damping for the inner elastic suspension system;

[0010] An end connection device for connecting the inner elastic suspension system and the outer elastic suspension system;

[0011] It also includes a limiting device for restricting the vertical movement of the external elastic suspension system.

[0012] The segmental model system of this application includes two sets of opposing inner elastic suspension systems, with segmental models connected between them. Each set of inner elastic suspension systems also has an outer elastic suspension system on its outer side. The inner elastic suspension systems can twist relative to the outer elastic suspension systems and drive the outer elastic suspension systems to move vertically. When applied in wind tunnel testing, it enables the segmental model to achieve coordinated vertical and torsional modes of motion. Furthermore, the inner and outer elastic suspension systems are connected by end-connecting devices, thereby limiting the torsion of the inner elastic suspension system relative to the outer elastic suspension system, allowing the segmental model system to achieve independent vertical movement of the segmental models. Further, a limiting device restricts the vertical movement of the outer elastic suspension system, thereby enabling the segmental model system to achieve independent torsional movement of the segmental models. The segmental model system of this application, through the cooperation of the end-connecting devices and the limiting devices… The system enables independent or coordinated vertical and torsional modes. Furthermore, it includes vertical damping adjustment devices at both ends of the external elastic suspension system, providing adjustable vertical damping for the external elastic suspension system. It also includes a torsional damping adjustment device located between the internal and external elastic suspension systems, providing adjustable torsional damping for the internal elastic suspension system. Through these vertical and torsional damping adjustment devices, independent adjustment of the vertical and torsional damping of the segmental model system is achieved, thereby enabling separate or simultaneous adjustment of the vertical and torsional damping of the segmental model system. This segmental model system overcomes the limitations of traditional segmental model elastic suspension systems, achieving direct separation and combination of vertical and torsional modes, as well as independent adjustment of the system's vertical and torsional damping, providing new technical support for vortex-induced vibration and flutter research.

[0013] Preferably, the inner elastic suspension system includes an inner suspension end plate, the outer elastic suspension system includes an outer suspension end plate, and the inner suspension end plate and the outer suspension end plate are located at the same height;

[0014] The segmental model includes a model end plate, and a central axis is provided inside the model end plate along the length direction of the model end plate. Both ends of the central axis extend to the outside of the model end plate.

[0015] The model end plate is bolted to the inner suspension end plate, and the inner suspension end plate is provided with a first central circular hole, and the end of the central shaft passes through the first central circular hole;

[0016] It also includes a rotating support shaft, which is rotatably disposed within the central shaft, and both ends of the rotating support shaft extend to the outside of the central shaft and are fixedly connected to the outer suspension end plate.

[0017] The model end plate is bolted to the inner suspension end plate, thus connecting the model end plate and the inner suspension end plate into one unit. During wind tunnel testing, the model end plate moves together with the inner suspension end plate after being affected by wind. Furthermore, the rotating support shaft is rotatably set inside the central shaft, and both ends of the rotating support shaft extend to the outside of the central shaft and are fixedly connected to the outer suspension end plate, so that the rotating support shaft and the central shaft can rotate relative to each other, and the inner suspension end plate can be torn relative to the outer suspension end plate.

[0018] Preferably, a hinged bearing is installed inside the end of the central shaft, and the outer ring of the hinged bearing abuts against the inner wall of the central shaft;

[0019] The inner ring of the hinged bearing is sleeved on the rotating support shaft.

[0020] The rotating support shaft and the central shaft are connected by a hinge bearing. When the inner suspension end plate moves vertically, the inner suspension end plate can drive the outer suspension end plate to move together. Through the above arrangement, the inner suspension end plate can not only be torsional relative to the outer suspension end plate, but also drive the outer suspension end plate to move vertically, so that the segment model system of this application can realize the coordinated movement of vertical and torsional modes.

[0021] Preferably, the torsional damping adjustment device includes a permanent magnet, a permanent magnet back iron, a conductor plate, a conductor plate back iron, and a spacing adjustment block. The permanent magnet back iron is connected to the side of the inner suspension end plate near the outer suspension end plate, and the permanent magnet is connected to the permanent magnet back iron.

[0022] The outer suspension end plate is detachably connected to the spacing adjustment block on the side near the inner suspension end plate, the conductor plate back iron is connected to the spacing adjustment block, and the conductor plate is connected to the conductor plate back iron.

[0023] The spacing between the conductor plate and the permanent magnet is adjusted by adjusting the thickness of the spacing adjustment block, thereby adjusting the magnitude of the torsional damping.

[0024] Preferably, the rotating support shaft passes sequentially through the spacing adjustment block, the conductor plate back iron, and the conductor plate and center;

[0025] The permanent magnet back iron is provided with a second central circular hole, the diameter of which is larger than the outer diameter of the rotating support shaft. The rotating support shaft passes through the second central circular hole and then enters the central shaft.

[0026] Preferably, the vertical damping adjustment device includes a permanent magnet, a permanent magnet back iron, a conductor plate, a conductor plate back iron, and a movable base. The permanent magnet back iron is connected to the side of the outer suspension end plate away from the inner suspension end plate, and the permanent magnet is connected to the permanent magnet back iron.

[0027] The conductor plate back iron is positioned opposite the permanent magnet back iron. The conductor plate is connected to the conductor plate back iron, and the bottom of the conductor plate back iron is connected to the movable base. The movable base can move the conductor plate back iron closer to or further away from the permanent magnet.

[0028] By moving the base, the conductor plate back iron moves closer to or further away from the permanent magnet, thereby adjusting the distance between the conductor plate and the permanent magnet, and thus adjusting the magnitude of the vertical damping.

[0029] Preferably, the movable base includes an optical axis rail, a ball screw, a slide table, and a bottom mold. The optical axis rail and the ball screw are horizontally mounted on the bottom mold. The slide table is sleeved on the optical axis rail and the ball screw. The ball screw is used to drive the slide table to move. The conductor plate back iron is connected to the top of the slide table.

[0030] Preferably, the limiting device includes a limiting track, a spherical contact, and a limiting screw. The limiting track is vertically disposed on the side of the outer suspension end plate away from the inner suspension end plate. The limiting track has a groove inside, the spherical contact is located in the groove, and the outer suspension end plate is connected to the spherical contact.

[0031] The limiting screw is slidably disposed within the groove, and the limiting screw is used to lock the spherical contact.

[0032] The external suspension end plate is connected to the spherical contact piece. The spherical contact piece is located in the groove of the limiting track. The limiting screw in the groove locks the spherical contact piece, thereby restricting the vertical movement of the external suspension end plate. This achieves the separation of the torsional motion mode of the segmental model system, which can only perform torsional motion and will not perform vertical motion, thus enabling the segmental model system to achieve a single torsional motion mode.

[0033] Preferably, the end connection device includes a connecting screw and an anti-misalignment connector, wherein the anti-misalignment connector abuts against the inner suspension end plate and the outer suspension end plate on both sides, and the connecting screw sequentially connects the outer suspension end plate, the anti-misalignment connector and the inner suspension end plate.

[0034] The outer suspension end plate and the inner suspension end plate are connected together by connecting screws and anti-misalignment connectors, thereby restricting the torsion of the inner suspension end plate relative to the outer suspension end plate, realizing the separation of the vertical motion modes of the segmental model system, which can only perform vertical motion and will not perform torsional motion, so that the segmental model system can achieve a single vertical motion mode.

[0035] Preferably, the internal elastic suspension system further includes a first suspension rod and a coil spring, and the internal suspension end plate is connected to the first suspension rod via the coil spring;

[0036] The external elastic suspension system also includes a second suspension rod and a coil spring, and the external suspension end plate is connected to the second suspension rod through the coil spring;

[0037] The two ends of the limiting track are connected to the rod of the external elastic suspension system by rigid connectors.

[0038] Preferably, based on the design mass m and vertical frequency f of the segment model... h Vertical damping ratio range (ξ) h,min ,ξ h,max ), calculate the vertical damping coefficient adjustment range (c) of the segmental model system. h,min ,c h,max ):

[0039] c h,min =2m·(2πf) h )·ξ h,min ,

[0040] c h,max =2m·(2πf) h )·ξ h,max ;

[0041] Based on the design mass moment of inertia I and torsional frequency f of the segment model. t Torsional damping ratio range (ξ) t,min ,ξ t,max ), calculate the adjustment range of the torsional damping coefficient of the segmental model system (c) t,min ,c t,max ):

[0042] c t,min =2I·(2πf) t )·ξ t,min ,

[0043] c t,max =2I·(2πf) t )·ξ t,max

[0044] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0045] The segmental model system of this application includes two sets of opposing inner elastic suspension systems, with segmental models connected between them. Each set of inner elastic suspension systems also has an outer elastic suspension system on its outer side. The inner elastic suspension systems can twist relative to the outer elastic suspension systems and drive the outer elastic suspension systems to move vertically. When applied in wind tunnel testing, it enables the segmental model to achieve coordinated vertical and torsional modes of motion. Furthermore, the inner and outer elastic suspension systems are connected by end-connecting devices, thereby limiting the torsion of the inner elastic suspension system relative to the outer elastic suspension system, allowing the segmental model system to achieve independent vertical movement of the segmental models. Further, a limiting device restricts the vertical movement of the outer elastic suspension system, thereby enabling the segmental model system to achieve independent torsional movement of the segmental models. The segmental model system of this application, through the cooperation of the end-connecting devices and the limiting devices… The system enables independent or coordinated vertical and torsional modes. Furthermore, it includes vertical damping adjustment devices at both ends of the external elastic suspension system, providing adjustable vertical damping for the external elastic suspension system. It also includes a torsional damping adjustment device located between the internal and external elastic suspension systems, providing adjustable torsional damping for the internal elastic suspension system. Through these vertical and torsional damping adjustment devices, independent adjustment of the vertical and torsional damping of the segmental model system is achieved, thereby enabling separate or simultaneous adjustment of the vertical and torsional damping of the segmental model system. This segmental model system overcomes the limitations of traditional segmental model elastic suspension systems, achieving direct separation and combination of vertical and torsional modes, as well as independent adjustment of the system's vertical and torsional damping, providing new technical support for vortex-induced vibration and flutter research. Attached Figure Description

[0046] Figure 1 This is a three-dimensional schematic diagram of the segmental model system.

[0047] Figure 2 This is a three-dimensional schematic diagram of the vertical damping adjustment device.

[0048] Figure 3 It is the bottom support of the vertical damping adjustment device.

[0049] Figure 4 This is a three-dimensional schematic diagram of an internal elastic suspension system.

[0050] Figure 5 This is a three-dimensional schematic diagram of a torsional damping adjustment device.

[0051] Figure 6 This is a three-dimensional schematic diagram of the segment model.

[0052] Figure 7 This is a three-dimensional schematic diagram of the limiting device.

[0053] Figure 8 This is a cross-sectional view of the connection between the limiting track and the spherical contact component.

[0054] Figure 9 This is a top view of the inner and outer suspension end plates.

[0055] Marked in the image:

[0056] 1-Segment model, 2-Model end plate, 3-Central shaft, 41-First lifting rod, 42-Second lifting rod, 5-Lifting ring, 6-Spring buckle, 71-Inner suspension end plate, 72-Outer suspension end plate, 8-Permanent magnet, 9-Permanent magnet back iron, 10-Conductor plate, 11-Conductor plate back iron, 12-Optical axis rail, 13-Ball screw, 14-Slide table, 15-Bottom support frame, 16-Side connecting rod, 17-Connecting screw, 18-Anti-misalignment connecting piece, 19-Hinged bearing, 20-Rotating support shaft, 21-Limiting rail, 22-Rigid connecting piece, 23-Spherical contact piece, 24-Limiting end rod, 25-Limiting screw, 26-Helical spring, 27-Handle, 28-Supporting angle steel, 29-Gap adjustment block, 30-Bottom mold. Detailed Implementation

[0057] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope 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.

[0058] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0059] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0060] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0061] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0062] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0063] Example 1

[0064] like Figures 1-9 As shown, a segmental model system for wind tunnel testing includes:

[0065] Two sets of opposing internal elastic suspension systems are connected by segment model 1. Each set of internal elastic suspension systems is also provided with an external elastic suspension system on the outside. The internal elastic suspension system can twist relative to the external elastic suspension system and drive the external elastic suspension system to move vertically.

[0066] A vertical damping adjustment device is installed on the side of the outer elastic suspension system away from the inner elastic suspension system, and is used to provide adjustable vertical damping for the outer elastic suspension system;

[0067] A torsional damping adjustment device is installed between the inner elastic suspension system and the outer elastic suspension system to provide adjustable torsional damping for the inner elastic suspension system.

[0068] End connection device for connecting the inner elastic suspension system and the outer elastic suspension system;

[0069] It also includes a limiting device to restrict the vertical movement of the external elastic suspension system.

[0070] The segmental model system of this embodiment includes two sets of opposing inner elastic suspension systems, with segmental models 1 connected between the inner elastic suspension systems. Each set of inner elastic suspension systems also has an outer elastic suspension system on its outer side. The inner elastic suspension system can twist relative to the outer elastic suspension system and drive the outer elastic suspension system to move vertically. When applied in wind tunnel tests, it enables the segmental model 1 to achieve coordinated vertical and torsional modes. Furthermore, the inner elastic suspension system and the outer elastic suspension system are connected by an end connection device, thereby restricting the twisting of the inner elastic suspension system relative to the outer elastic suspension system, enabling the segmental model system to achieve independent vertical movement of the segmental model 1. Furthermore, the vertical movement of the outer elastic suspension system is restricted by a limiting device, thereby enabling the segmental model system to achieve independent torsional movement of the segmental model 1. The segmental model system of this embodiment, through the combined use of the end connection device and the limiting device, can achieve independent or coordinated vertical and torsional modes, enabling the segmental model system to have the conversion and adjustment of a single degree of freedom (vertical or torsional) and two degrees of freedom (vertical and torsional).

[0071] The segmental model system of this embodiment also includes vertical damping adjustment devices disposed at both ends of the external elastic suspension system, which provide adjustable vertical damping for the external elastic suspension system; it also includes a torsional damping adjustment device disposed between the internal elastic suspension system and the external elastic suspension system, which provides adjustable torsional damping for the internal elastic suspension system. Through the vertical damping adjustment device and the torsional damping adjustment device, the vertical and torsional damping of the segmental model system can be independently adjusted, thereby realizing the separate or synchronous adjustment of the vertical and torsional damping of the segmental model system. The segmental model system of this embodiment breaks through the limitations of traditional segmental model elastic suspension systems, realizes the direct separation and combination of vertical and torsional modes, as well as the independent adjustment of the vertical and torsional damping of the system, providing new technical support for the study of vortex-induced vibration and flutter.

[0072] In one or more implementations, such as Figure 1 As shown, the inner elastic suspension system includes an inner suspension end plate 71, and the outer elastic suspension system includes an outer suspension end plate 72. The inner suspension end plate 71 and the outer suspension end plate 72 are located at the same height.

[0073] like Figure 6 As shown, the model end plate 2 is bolted to the inner suspension end plate 71. The inner suspension end plate 71 is provided with a first central circular hole. The end of the central shaft 3 passes through the first central circular hole and extends out of the inner suspension end plate 71.

[0074] It also includes a rotating support shaft 20, which is rotatably disposed inside the central shaft 3, and both ends of the rotating support shaft 20 extend to the outside of the central shaft 3 and are fixedly connected to the outer suspension end plate 72.

[0075] Both ends of the model end plate 2 are bolted to the inner suspension end plate 71, thus connecting the model end plate 2 and the inner suspension end plate 71 into one unit. This allows the model end plate 2 to move in tandem with the inner suspension end plate 71 under wind influence during wind tunnel testing. Furthermore, the rotating support shaft 20 is rotatably mounted within the central shaft 3, with both ends extending to the outside of the central shaft 3 and fixedly connected to the outer suspension end plate 72. This allows the rotating support shaft 20 and the central shaft 3 to rotate relative to each other, enabling the inner suspension end plate 71 to twist relative to the outer suspension end plate 72.

[0076] In optional implementations, such as Figure 4 As shown, a hinge bearing 19 is installed inside the end of the central shaft 3, and the outer ring of the hinge bearing 19 abuts against the inner wall of the central shaft 3.

[0077] The inner ring of the hinge bearing 19 is fitted onto the rotating support shaft 20.

[0078] The rotating support shaft 20 and the central shaft 3 are connected by a hinge bearing 19. When the inner suspension end plate 71 moves vertically, the inner suspension end plate 71 can drive the outer suspension end plate 72 to move together. Through the above arrangement, the inner suspension end plate 71 can not only twist relative to the outer suspension end plate 72, but also drive the outer suspension end plate 72 to move vertically, so that the segment model system of this embodiment can realize the coordinated movement of vertical and torsional modes.

[0079] In optional implementations, such as Figure 6 As shown, the central axis 3 is located at the center of the end of the model end plate 2, which helps to distribute the load evenly, reduce the stress and vibration caused by eccentric load, improve stability, and avoid additional torque caused by asymmetry.

[0080] A first central circular hole is provided on the inner suspension end plate 71, the central shaft 3 passes through the first central circular hole and extends out of the inner suspension end plate 71, the rotating support shaft 20 passes through the central shaft 3, and the two ends of the rotating support shaft 20 are respectively fixed at the center of the two outer suspension end plates 72.

[0081] In this embodiment, both ends of the model end plate 2 are bolted to the inner suspension end plate 71. The central shaft 3 passes through the inner suspension end plate 71. When it is necessary to adjust the angle of attack, the bolts connecting the model end plate 2 and the inner suspension end plate 71 are removed. Then, the model end plate 2 is rotated appropriately so that it can rotate relative to the inner suspension end plate 71. After adjusting the angle of attack, the model end plate 2 and the inner suspension end plate 71 are bolted together.

[0082] In one or more implementations, such as Figure 1 , Figure 4 As shown, the internal elastic suspension system also includes a first suspension rod 41, a suspension ring 5, a spring buckle 6, and a coil spring 26. The inner suspension end plate 71 is provided with a first suspension rod 41 in both the upper and lower areas. The inner suspension end plate 71 is connected to the coil spring 26 through the spring buckle 6. The coil spring 26 is connected to the first suspension rod 41 through the spring buckle 6 and the suspension ring 5. Furthermore, two coil springs 26 are connected to the upper part of the inner suspension end plate 71 and two coil springs 26 are also connected to the lower part of the inner suspension end plate 71. The inner suspension end plate 71 is suspended between the first suspension rods 41 by the four coil springs 26.

[0083] The external elastic suspension system also includes a second suspension rod 42, a coil spring 26, a hanging ring 5, a spring buckle 6, and a coil spring 26. The upper and lower areas of the external suspension end plate 72 are provided with the second suspension rod 42. The external suspension end plate 72 is connected to the coil spring 26 through the spring buckle 6. The coil spring 26 is connected to the second suspension rod 42 through the spring buckle 6 and the hanging ring 5. Furthermore, two coil springs 26 are connected to the upper part of the external suspension end plate 72 and two coil springs 26 are also connected to the lower part of the external suspension end plate 72. The external suspension end plate 72 is suspended between the second suspension rods 42 by the four coil springs 26.

[0084] Both the first suspender 41 and the second suspender 42 are connected to the upper and lower fixed boundaries of the wind tunnel.

[0085] The internal elastic suspension system provides torsional stiffness to the segmental model system, while the internal and external elastic suspension systems together provide vertical stiffness to the segmental model system.

[0086] In an optional implementation, both the torsional damping adjustment device and the vertical damping adjustment device are permanent magnet plate type eddy current dampers.

[0087] In one or more implementations, such as Figure 5 As shown, the torsional damping adjustment device includes a permanent magnet 8, a permanent magnet back iron 9, a conductor plate 10, a conductor plate back iron 11, and a spacing adjustment block 29. The permanent magnet back iron 9 is connected to the inner suspension end plate 71 on the side near the outer suspension end plate 72, and the permanent magnet 8 is connected to the permanent magnet back iron 9.

[0088] The outer suspension end plate 72 is detachably connected to the spacing adjustment block 29 on the side near the inner suspension end plate 71. The conductor plate back iron 11 is connected to the spacing adjustment block 29, and the conductor plate 10 is connected to the conductor plate back iron 11.

[0089] The spacing between the conductor plate 10 and the permanent magnet 8 is adjusted by adjusting the thickness of the spacing adjustment block 29, thereby adjusting the magnitude of the torsional damping. In use, multiple spacing adjustment blocks 29 of different thicknesses are set, inserted into the corresponding positions, and then fixed to the outer suspension end plate 72 by long bolt rods. The material used for the spacing adjustment block 29 can be lightweight wood blocks or other lightweight and high-strength materials.

[0090] In optional implementations, such as Figure 5 As shown, the torsional damping adjustment device is located at the center of the inner suspension end plate 71 and the outer suspension end plate 72. The rotating support shaft 20 passes through the center of the spacing adjustment block 29, the conductor plate back iron 11 and the conductor plate 10 in sequence. The permanent magnet back iron 9 is provided with a second central circular hole. The diameter of the second central circular hole is larger than the outer diameter of the rotating support shaft 20. The second central circular hole allows the rotating support shaft 20 to pass through without contacting it. The permanent magnet 8 is fixed to the permanent magnet back iron 9 by non-magnetic bolts. The conductor plate 10, the conductor plate back iron 11 and the spacing adjustment block 29 are connected together in sequence by bolts and fixed to the inner center position of the outer suspension end plate 72.

[0091] Permanent magnets 8 are arranged at intervals along the circumferential axis of rotation support 20, and the number of them is not less than four.

[0092] In one or more implementations, such as Figure 1 , Figure 2 As shown, the vertical damping adjustment device includes a permanent magnet 8, a permanent magnet back iron 9, a conductor plate 10, a conductor plate back iron 11, and a movable base. The permanent magnet back iron 9 is connected to the side of the outer suspension end plate 72 away from the inner suspension end plate 71, and the permanent magnet 8 is connected to the permanent magnet back iron 9.

[0093] The conductor plate back iron 11 is positioned relative to the permanent magnet back iron 9. The conductor plate 10 is connected to the conductor plate back iron 11. The bottom of the conductor plate back iron 11 is connected to a movable base. The movable base can move the conductor plate back iron 11 closer to or further away from the permanent magnet 8.

[0094] By moving the base, the conductor plate back iron 11 moves closer to or further away from the permanent magnet 8, thereby adjusting the distance between the conductor plate 10 and the permanent magnet 8, and thus adjusting the magnitude of the vertical damping.

[0095] In optional implementations, such as Figure 2As shown, the vertical damping adjustment device is set at both ends of the external suspension end plate 72, that is, permanent magnet back irons 9 are installed at both ends of the external suspension end plate 72, and then conductor plate back irons 11 are set relative to the permanent magnet back irons 9. Permanent magnets 8 are set on the permanent magnet back irons 9, and conductor plates 10 are set on the side of the conductor plate back irons 11 close to the permanent magnets 8. A movable base is set at the bottom of the conductor plate back irons 11.

[0096] In optional implementations, such as Figure 2 As shown, the movable base includes an optical axis rail 12, a ball screw 13, a slide 14, and a bottom mold 30. The optical axis rail 12 and the ball screw 13 are horizontally mounted on the bottom mold 30. The slide 14 is sleeved on the optical axis rail 12 and the ball screw 13. The ball screw 13 is used to drive the slide 14 to move. The conductor plate back iron 11 is connected to the top of the slide 14.

[0097] Among them, there are no fewer than two optical axis rails 12. The optical axis rails 12 provide sliding support for the slide table 14. The slide table 14 is moved by rotating the ball screw 13. When the slide table 14 moves, it drives the conductor plate back iron 11 to move, thereby realizing the adjustment of the distance between the conductor plate 10 and the permanent magnet 8.

[0098] Furthermore, the permanent magnet 8 is fixed to the permanent magnet back iron 9 by non-magnetic bolts, the conductor plate 10 and the conductor plate back iron 11 are fixed together by bolts, and the conductor plate back iron 11 is fixed to the slide table 14 by the supporting angle steel 28.

[0099] Furthermore, a rocker arm 27 is provided at the end of the ball screw 13, and the ball screw 13 is rotated by rotating the rocker arm 27.

[0100] In an optional embodiment, the bottom mold 30 is mounted on the bottom support frame 15, and the bottom support frame 15 is connected to the limiting track 21 of the limiting device via the lateral connecting rod 16.

[0101] In one or more implementations, such as Figure 1 , Figure 7 As shown, the limiting device includes a limiting rail 21, a spherical contact 23, and a limiting screw 25. The limiting rail 21 is vertically arranged on the side of the outer suspension end plate 72 away from the inner suspension end plate 71. The limiting rail 21 has a groove inside, and the spherical contact 23 is located in the groove. The outer suspension end plate 72 is connected to the spherical contact 23.

[0102] The limiting screw 25 is slidably disposed in the slide groove, and the limiting screw 25 is used to lock the spherical contact 23.

[0103] The external suspension end plate 72 is connected to the spherical contact member 23. The spherical contact member 23 is located in the groove of the limiting track 21. The limiting screw 25 in the groove holds the spherical contact member 23, thereby restricting the vertical movement of the external suspension end plate 72. This achieves the separation of the torsional motion mode of the segmental model system, which can only perform torsional motion and will not perform vertical motion, so that the segmental model system can achieve a single torsional motion mode.

[0104] Furthermore, the limiting track 21 can restrict the torsional movement of the outer suspension end plate 72 of the outer elastic suspension system. During the test, due to the friction of the hinge bearing 19, the relative rotation of the inner elastic suspension system will add a torsional torque to the outer elastic suspension system, which can easily cause the outer suspension end plate 72 to twist. In addition, the model under wind is prone to horizontal lateral displacement along the wind direction, which will cause the coil spring 26 of the outer elastic suspension system to tilt horizontally to a certain extent, which is not conducive to system stability. To overcome the above disadvantages, the outer suspension end plate 72 is connected to the spherical contact member 23 through the limiting end rod 24. The spherical contact member 23 is located in the groove of the limiting track 21, so the cooperation between the spherical contact member 23 and the groove can limit the torsion and horizontal lateral displacement of the outer suspension end plate 72.

[0105] In an optional embodiment, the external suspension end plate 72 is connected to the spherical contact member 23 via the limiting end rod 24.

[0106] In an optional embodiment, the segmental model system has two limiting tracks 21 on each side, wherein each limiting track 21 is equipped with at least one spherical contact 23, and the spherical contact 23 is uniformly connected to the outer suspension end plate 72.

[0107] In one or more implementations, such as Figure 9 As shown, the end connection device includes a connecting screw 17 and an anti-misalignment connector 18. The anti-misalignment connector 18 abuts against the inner suspension end plate 71 and the outer suspension end plate 72 on both sides, respectively. The connecting screw 17 connects the outer suspension end plate 72, the anti-misalignment connector 18 and the inner suspension end plate 71 in sequence.

[0108] The outer suspension end plate 72 and the inner suspension end plate 71 are connected together by the connecting screw 17 and the anti-misalignment connector 18, thereby restricting the inner suspension end plate 71 from twisting relative to the outer suspension end plate 72, realizing the separation of the vertical motion modes of the segment model system, which can only perform vertical motion and will not perform torsional motion, so that the segment model system can realize a single vertical motion mode.

[0109] In this embodiment, the end connection device can be located in the middle area of ​​the inner and outer suspension end plates, or it can be located on both sides of the inner and outer suspension end plates.

[0110] In one or more implementations, such as Figure 1As shown, the internal elastic suspension system also includes a first suspension rod 41 and a coil spring 26, and the internal suspension end plate 71 is connected to the first suspension rod 41 through the coil spring 26;

[0111] The external elastic suspension system also includes a second suspension rod 42 and a coil spring 26, with the external suspension end plate 72 connected to the second suspension rod 42 via the coil spring 26;

[0112] The two ends of the limiting track 21 are connected to the second hanger 42 of the external elastic suspension system by rigid connectors 22.

[0113] In this embodiment, the model end plate 2 and the central shaft 3 form the basic skeleton of the segment model 1; the inner elastic suspension system provides torsional stiffness for the segment model system, and the inner and outer elastic suspension systems together provide vertical stiffness for the segment model system; the torsional damping adjustment device only provides torsional damping for the segment model system, and the torsional damping magnitude can be precisely and continuously adjusted by changing the gap between the permanent magnet 8 and the conductor plate 10 through the thickness of the spacing adjustment block 29; the vertical damping adjustment device only provides vertical damping for the segment model system, and the vertical damping magnitude can be precisely and continuously adjusted by changing the gap between the permanent magnet 8 and the conductor plate 10 through the moving base; the end connection device selects whether to limit the relative rotation of the suspension end plates of the inner and outer elastic suspension systems by setting the connecting screw 17 and the anti-misalignment connector 18 at the gap position of the two sets of elastic suspension systems according to the experimental requirements for the segment model motion mode; the limiting device can limit the vertical movement of the outer suspension end plate 72 of the outer elastic suspension system by tightening the limiting screw 25 in the limiting rail 21.

[0114] Example 2

[0115] Based on Example 1, this example discloses a workflow for a segmental model system used in wind tunnel testing, as follows:

[0116] (1) Determine the motion modes (vertical motion, torsional motion, and two-degree-of-freedom motion) that the segmental model system needs to possess in the wind tunnel test according to the research objectives;

[0117] (2) Design the segmental model system according to the required motion mode and dynamic characteristic parameters (mass, damping, frequency) of the segmental model system. The design methods of the segmental model system under different motion modes are as follows:

[0118] (I) Vertical motion with one degree of freedom

[0119] 1) Based on the design mass m and vertical frequency f of segment model 1 h Calculate the total vertical stiffness K of the segmental model system. h ;

[0120] K h=m·(2πf) h ) 2 (1)

[0121] Wherein, the design mass m of segment model 1 is the total mass of the segment model system participating in vertical vibration, which includes the mass of the inner and outer suspension end plates and their attached components, the mass of segment model 1, and approximately 1 / 3 of the mass of the helical spring 26.

[0122] 2) Based on the total vertical stiffness K of the segmental model system h The total vertical stiffness K of the internal and external elastic suspension systems is distributed. 1,h and K 2,h ;

[0123] K 1,h =λ h K h (2)

[0124] K 2,h =(1-λ) h )K h (3)

[0125] In the formula, λ h This is the total vertical stiffness distribution coefficient of the internal elastic suspension system.

[0126] 3) Based on the total vertical stiffness K of the inner and outer elastic suspension systems 1,h and K 2,h Calculate the stiffness k of a single coil spring in the inner and outer elastic suspension systems. 1,h and k 2,h ;

[0127] k 1,h =K 1,h / 8 (4)

[0128] k 2,h =K 2,h / 8 (5)

[0129] 4) Based on the stiffness k of a single coil spring in the inner and outer elastic suspension system (26 kJ / kg). 1,h and k 2,h And the spring stiffness calculation formula (6), design and process the spring, and determine the spring design parameters;

[0130]

[0131] In the formula, k is the stiffness of the designed spring, G is the shear modulus, d is the diameter of the spring wire, D is the mean diameter of the spring coil, and n is the number of effective coils.

[0132] 5) Based on the design mass m and vertical frequency f of the segment model h Vertical damping ratio range (ξ)h,min ,ξ h,max ), calculate the vertical damping coefficient adjustment range (c) of the segmental model system. h,min ,c h,max );

[0133] c h,min =2m·(2πf) h )·ξ h,min (7)

[0134] c h,max =2m·(2πf) h )·ξ h,max (8)

[0135] 6) The vertical damping coefficient adjustment range (c) of the segmental model system is calculated. h,min ,c h,max Ignoring the initial vertical damping coefficient of the system (which is usually small), design a system that can provide (c h,min ,c h,max A plate-type eddy current damper with a vertical damping coefficient within a certain range is required, which must have stable performance and a reasonable spacing adjustment range.

[0136] 7) Construct a segmental model elastic suspension system according to the connection relationship of each component. Connecting screws 17 and anti-misalignment connectors 18 are set at the gap between the inner and outer elastic suspension systems to restrict the relative rotation of the suspension end plates of the inner and outer elastic suspension systems. The fastening position of the limiting screws 25 in the limiting rail 21 does not restrict the vertical movement of the outer suspension end plate 72 of the outer elastic suspension system.

[0137] (II) Single-degree-of-freedom torsional motion

[0138] 1) Based on the design mass moment of inertia I and torsional frequency f of segment model 1 t Calculate the total torsional stiffness K of the segmental model system. t ;

[0139] K t =I·(2πf) t ) 2 (9)

[0140] Among them, the design mass moment of inertia I of segment model 1 is the total mass moment of inertia (about the central axis of the model) of the segment model system that participates in torsional vibration. It is the total mass moment of inertia including the mass moment of inertia of the inner suspension end plate 71 and its attached components, the mass moment of inertia of segment model 1, and about 1 / 3 (connected to the inner suspension end plate 71) of the helical spring 26.

[0141] 2) Based on the total torsional stiffness K of the segmental model system t Calculate the stiffness k of a single coil spring in the internal elastic suspension system.1,t ;

[0142] k 1,t =K t / (2l 1,t 2 (10)

[0143] In the formula, l 1,t This refers to the spring spacing on the same side of the internal elastic suspension system.

[0144] 3) The single coil spring of the external elastic suspension system has a stiffness of 26 k. 2,t Spacing l with springs on the same side 2,t The springs of the external elastic suspension system can be selected arbitrarily, or they can be removed. Recommended values ​​are:

[0145] k 2,t =k 1,t (11)

[0146] l 2,t =l 1,t (12)

[0147] 4) Based on the stiffness k of a single coil spring in the inner and outer elastic suspension system (26 kJ / kg). 1,t and k 2,t And the spring stiffness calculation formula (6), design and process the spring;

[0148] 5) Based on the design mass moment of inertia I and torsional frequency f of segment model 1 t Torsional damping ratio range (ξ) t,min ,ξ t,max ), calculate the adjustment range of the torsional damping coefficient of the segmental model system (c) t,min ,c t,max );

[0149] c t,min =2I·(2πf) t )·ξ t,min (13)

[0150] c t,max =2I·(2πf) t )·ξ t,max (14)

[0151] 6) Adjustment range of the torsional damping coefficient of the segmental model system (c) is calculated. t,min ,c t,max Ignoring the initial torsional damping coefficient of the system (which is usually small), design a system that can provide (c) to the system. t,min ,c t,max Plate eddy current dampers with a torsional damping coefficient within a certain range are required to have stable performance and a reasonable spacing adjustment range.

[0152] 7) Construct a segmental model elastic suspension system according to the connection relationship of each component. The suspension end plates of the inner and outer elastic suspension systems can rotate relative to each other. The fastening position of the inner limit screw 25 of the limit track 21 locks the spherical contact 23, restricting the vertical movement of the outer suspension end plate 72 of the outer elastic suspension system.

[0153] (III) Two-degree-of-freedom vertical and torsional motion

[0154] 1) Based on the design mass moment of inertia I and torsional frequency f of segment model 1 t Calculate the total torsional stiffness K of the segmental model system. t ′;

[0155] K t ′=I·(2πf t ) 2 (15)

[0156] 2) Based on the total torsional stiffness K of the segmental model system t Calculate the stiffness k of a single coil spring in the internal elastic suspension system. 1,t ;

[0157] k 1,t =K t ′ / (2l 1,t 2 (16)

[0158] In the formula, l 1,t This refers to the spring spacing on the same side of the internal elastic suspension system.

[0159] 3) Based on the design mass m and vertical frequency f of segment model 1 h Calculate the total vertical stiffness K′ of the segmental model system. h ;

[0160] K′h=m·(2πfh) 2 (17)

[0161] 4) Based on the total vertical stiffness K′ of the segmental model system h Calculate the total vertical stiffness K′ of the external elastic suspension system. 2,h ;

[0162] K′ 2,h =K′ h -8k 1,t (18)

[0163] 5) Based on the total vertical stiffness K′ of the external elastic suspension system 2,h Calculate the stiffness k of a single coil spring 26 in the external elastic suspension system. 2,h ;

[0164] k 2,h =K′ 2,h / 8 (19)

[0165] 3) The spacing l of the coil springs 26 on the same side of the external elastic suspension system 2,t You can choose any value, but we recommend the following:

[0166] l2,t=l1,t (20)

[0167] 4) Based on the stiffness k of the single coil spring 26 of the inner and outer elastic suspension system 1,t and k 2,h And the spring stiffness calculation formula (6), design and process the spring;

[0168] 5) Based on the design mass moment of inertia I and torsional frequency f of segment model 1 t Torsional damping ratio range (ξ) t,min ,ξ t,max ), calculate the adjustment range of the torsional damping coefficient of the segmental model system (c) t,min ,c t,max );

[0169] c t,min =2I·(2πf) t )·ξ t,min (twenty one)

[0170] c t,max =2I·(2πf) t )·ξ t,max (twenty two)

[0171] 6) Based on the design mass m and vertical frequency f of segment model 1 h Vertical damping ratio range (ξ) h,min ,ξ h,max ), calculate the vertical damping coefficient adjustment range (c) of the segmental model system. h,min ,c h,max );

[0172] c h,min =2m·(2πf) h )·ξ h,min (twenty three)

[0173] c h,max =2m·(2πf) h )·ξ h,max (twenty four)

[0174] 7) Adjustment range of the torsional damping coefficient of the segmental model system (c) is calculated. t,min ,c t,maxIgnoring the initial torsional damping coefficient of the system, a design is made that can provide (c) for the system. t,min ,c t,max Plate eddy current dampers with a torsional damping coefficient within a certain range are required to have stable performance and a reasonable spacing adjustment range.

[0175] 8) Adjustment range of the torsional damping coefficient of the segmental model system (c) based on the calculated values. t,min ,c t,max Ignoring the initial torsional damping coefficient of the system, a design is made that can provide (c) for the system. t,min ,c t,max Plate eddy current dampers with a torsional damping coefficient within a certain range are required to have stable performance and a reasonable spacing adjustment range.

[0176] 9) Construct a segmental model elastic suspension system according to the connection relationship of each component. The suspension end plates of the inner and outer elastic suspension systems can rotate relative to each other. The restriction of the inner limit screw 25 of the limit track 21 on the spherical contact 23 is removed. The outer suspension end plate 72 of the outer elastic suspension system can move vertically.

[0177] (3) Adjust the assembled segmental model system for wind tunnel testing.

[0178] The above description is only a preferred embodiment of the present invention and is 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 protection scope of the present invention.

Claims

1. A segmental model system for wind tunnel testing, characterized in that, include: Two sets of opposing internal elastic suspension systems are connected by a segment model (1). Each set of internal elastic suspension systems is also provided with an external elastic suspension system on the outside. The internal elastic suspension system can twist relative to the external elastic suspension system and drive the external elastic suspension system to move vertically. A vertical damping adjustment device is installed at both ends of the external elastic suspension system to provide adjustable vertical damping for the external elastic suspension system; A torsional damping adjustment device is disposed between the inner elastic suspension system and the outer elastic suspension system, for providing adjustable torsional damping for the inner elastic suspension system; An end connection device for connecting the inner elastic suspension system and the outer elastic suspension system; It also includes a limiting device for restricting the vertical movement of the external elastic suspension system; The inner elastic suspension system includes an inner suspension end plate (71), and the outer elastic suspension system includes an outer suspension end plate (72). The inner suspension end plate (71) and the outer suspension end plate (72) are located at the same height. The segment model (1) includes a model end plate (2), and a central axis (3) is provided inside the model end plate (2) along the length direction of the model end plate (2). Both ends of the central axis (3) extend to the outside of the model end plate (2). The model end plate (2) is bolted to the inner suspension end plate (71), and the inner suspension end plate (71) is provided with a first central circular hole, and the end of the central shaft (3) passes through the first central circular hole; It also includes a rotating support shaft (20), which is rotatably disposed inside the central shaft (3), and both ends of the rotating support shaft (20) extend to the outside of the central shaft (3) and are fixedly connected to the external suspension end plate (72); The torsional damping adjustment device includes a permanent magnet (8), a permanent magnet back iron (9), a conductor plate (10), a conductor plate back iron (11), and a spacing adjustment block (29). The permanent magnet back iron (9) is connected to the side of the inner suspension end plate (71) near the outer suspension end plate (72), and the permanent magnet (8) is connected to the permanent magnet back iron (9). The outer suspension end plate (72) is detachably connected to the spacing adjustment block (29) on the side near the inner suspension end plate (71), the conductor plate back iron (11) is connected to the spacing adjustment block (29), and the conductor plate (10) is connected to the conductor plate back iron (11). The vertical damping adjustment device includes a permanent magnet (8), a permanent magnet back iron (9), a conductor plate (10), a conductor plate back iron (11), and a movable base. The permanent magnet back iron (9) is connected to both ends of the external suspension end plate (72), and the permanent magnet (8) is connected to the permanent magnet back iron (9). The conductor plate back iron (11) is disposed opposite to the permanent magnet back iron (9), the conductor plate (10) is connected to the conductor plate back iron (11), the bottom of the conductor plate back iron (11) is connected to the movable base, and the movable base can drive the conductor plate back iron (11) to move closer to or away from the permanent magnet (8). Based on the design quality of the segment model (1) m and vertical frequency f h Vertical damping ratio range ( ξ h,min , ξ h,max ), calculate the vertical damping coefficient adjustment range of the segmental model system ( c h,min , c h,max ): ， ； Based on the design mass moment of inertia of the segment model (1) I and torsional frequency f t Torsional damping ratio range ( ξ t,min , ξ t,max ), calculate the adjustment range of the torsional damping coefficient of the segmental model system ( c t,min , c t,max ): ， 。 2. The segmental model system for wind tunnel testing according to claim 1, characterized in that, A hinge bearing (19) is installed inside the end of the central shaft (3), and the outer ring of the hinge bearing (19) abuts against the inner wall of the central shaft (3). The inner ring of the hinge bearing (19) is fitted onto the rotating support shaft (20).

3. The segmental model system for wind tunnel testing according to claim 1, characterized in that, The rotating support shaft (20) passes through the center of the spacing adjustment block (29), the conductor plate back iron (11), and the conductor plate (10) in sequence; The permanent magnet back iron (9) is provided with a second central circular hole. The diameter of the second central circular hole is larger than the outer diameter of the rotating support shaft (20). The rotating support shaft (20) passes through the second central circular hole and then enters the central shaft (3).

4. A segmental model system for wind tunnel testing according to claim 1, characterized in that, The movable base includes an optical axis rail (12), a ball screw (13), a slide (14), and a bottom mold (30). The optical axis rail (12) and the ball screw (13) are horizontally mounted on the bottom mold (30). The slide (14) is sleeved on the optical axis rail (12) and the ball screw (13). The ball screw (13) is used to drive the slide (14) to move. The conductor plate back iron (11) is connected to the top of the slide (14).

5. A segmental model system for wind tunnel testing according to claim 1, characterized in that, The limiting device includes a limiting rail (21), a spherical contact (23), and a limiting screw (25). The limiting rail (21) is vertically arranged on the side of the outer suspension end plate (72) away from the inner suspension end plate (71). The limiting rail (21) has a groove inside. The spherical contact (23) is located in the groove. The outer suspension end plate (72) is connected to the spherical contact (23). The limiting screw (25) is slidably disposed in the groove, and the limiting screw (25) is used to lock the spherical contact (23).

6. A segmental model system for wind tunnel testing according to claim 5, characterized in that, The end connection device includes a connecting screw (17) and an anti-misalignment connector (18). The anti-misalignment connector (18) abuts against the inner suspension end plate (71) and the outer suspension end plate (72) on both sides respectively. The connecting screw (17) is connected to the outer suspension end plate (72), the anti-misalignment connector (18) and the inner suspension end plate (71) in sequence.

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