An experimental device for the flow-induced vibration response of a horizontal cylinder under wave-current coupling conditions

Abstract

The present invention discloses a test device for the flow-induced vibration response of a horizontal cylinder under wave-current coupling conditions, which relates to the field of fluid mechanics experimental technology and includes a fixing system and a vibration system; the fixing system includes fixed supports fixedly connected to the tops of both sides of a wave-current circulation water tank, an adapter plate fixedly connected between the two fixed supports, and a vertical guide rail mounting base plate installed on the adapter plate; the vibration system includes a slider mounting plate that slides vertically on one side of the guide rail mounting base plate, an elastic connector is also provided between the slider mounting plate and the top of the guide rail mounting base plate, an H-shaped support structure is connected below the slider mounting plate, and the end of the H-shaped support structure away from the slider mounting plate extends into the wave-current circulation water tank and connects to the test cylinder, and the test cylinder is arranged horizontally. The present invention solves the defect that traditional test devices cannot be applied to horizontal test cylinders and wave-current coupling working conditions, and can meet the vibration response tests of horizontal test cylinders under three different working conditions: pure flow, pure wave, and wave-current coupling.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid mechanics experiments, and in particular to a test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions. Background Art

[0002] There are various ways to exploit ocean current energy. Flow-induced vibration power generation, due to its low starting velocity, is particularly well-suited to low-velocity environments. However, when ocean currents flow past marine engineering structures, they generate alternating vortex shedding behind them, subjecting them to periodic hydrodynamic forces and inducing flow-induced vibration. This flow-induced vibration power generation method, with its low starting velocity, is well-suited for exploiting ocean current energy in low-velocity environments.

[0003] Ocean currents exhibit shear flow characteristics, with current velocities high near the water surface and rapidly decreasing with depth. Therefore, to fully utilize ocean current energy, flow-induced vibration power generation devices should be located close to the water surface, where the influence of surface waves cannot be ignored. Wave-current coupling is a key and unavoidable challenge in the efficient utilization of flow-induced vibration technology.

[0004] However, existing cylindrical flow-induced vibration test devices are mainly used to test vertical cylinders under pure flow, such as the test devices disclosed in Chinese invention patents such as CN118500666A and CN104048810A, which do not meet the requirements of horizontal cylindrical flow-induced vibration response tests under wave-current coupling conditions.

[0005] Therefore, a test device for the flow-induced vibration response of a horizontal cylinder under wave-current coupling conditions is needed. Summary of the Invention

[0006] The purpose of the present invention is to provide a horizontal cylindrical flow-induced vibration response test device under wave-current coupling conditions to solve the above-mentioned technical problems existing in the prior art.

[0007] To achieve the above-mentioned purpose, the present invention provides the following scheme: a test device for the flow-induced vibration response of a horizontal cylindrical body under wave-current coupling conditions, comprising a fixing system and a vibration system; the fixing system comprises a fixing support fixedly connected to the tops of both sides of a wave-current circulation water tank, an adapter plate fixedly connected between the two fixing supports, and a vertical guide rail mounting base plate installed on the adapter plate; the vibration system comprises a slider mounting plate vertically sliding on one side of the guide rail mounting base plate, an elastic connecting member is further provided between the slider mounting plate and the top of the guide rail mounting base plate, the elastic connecting member is a spring connected between the guide rail mounting base plate and the slider mounting plate, and the spring is provided in two groups; below the slider mounting plate An H-shaped support structure is connected, and a crossbeam is connected to the H-shaped support structure near the position of the slider mounting plate. The end of the H-shaped support structure away from the slider mounting plate extends into the wave circulation water tank and is connected to the test cylinder, and the test cylinder is arranged horizontally; the test cylinder is detachably connected to the bottom end of the H-shaped support structure, and the gravity and volume of the test cylinder are adjustable; the guide rail mounting base plate and the slider mounting plate are respectively connected to the first spring support and the second spring support, and the two ends of the spring are connected to the first spring support and the second spring support; a spring raising plate is installed on the guide rail mounting base plate, and the first spring support is adjustably mounted on the spring raising plate.

[0008] Optionally, the springs are provided in two groups.

[0009] Optionally, two guide rails are provided on a surface of the guide rail mounting base plate facing the slider mounting plate, and two sliders are correspondingly provided on the slider mounting plate, and the two sliders are slidably engaged with the two guide rails.

[0010] Optionally, upper and lower limit blocks are provided at the upper and lower ends of the guide rail respectively.

[0011] Compared with the prior art, the present invention has at least the following beneficial effects:

[0012] 1. The present invention solves the defect that the traditional cylindrical flow-induced vibration test device cannot be applied to horizontal test cylinders and wave-flow coupling working conditions. It can meet the vibration response tests of horizontal test cylinders under three different working conditions: pure flow, pure wave, and wave-flow coupling, and has wide applicability.

[0013] 2. The present invention cleverly utilizes the spring to balance the difference between the gravity and buoyancy of the test cylinder, so that the test cylinder is initially stationary at a predetermined water depth.

[0014] 3. The present invention can ensure that the cylinder remains stationary at the same position in its initial state under different spring parameters by adjusting the spring stiffness coefficient and the damping coefficient and adjusting the spring suspension point.

[0015] 4. The test equipment of the present invention can replace the cylinder, so that vibration response tests can be performed on different cylinders, and the equipment has wide applicability.

[0016] 5. The test equipment of the present invention is simple and reliable, has low manufacturing cost and is easy to maintain while ensuring that the test requirements are met. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a front view of an embodiment of the present invention installed on a wave flow circulation water tank;

[0019] Figure 2 This is an axonometric view of an embodiment of the present invention installed on a wave-flow circulating water tank;

[0020] Figure 3 for Figure 2 A partial enlarged view of point A in the middle;

[0021] Figure 4 A front view of an embodiment of the present invention;

[0022] Figure 5 is an axonometric diagram of an embodiment of the present invention;

[0023] Figure 6 This is a schematic structural diagram of a fixing system according to an embodiment of the present invention;

[0024] Figure 7 The structure of the vibration system in the embodiment of the present invention is shown in FIG. Figure 1 ;

[0025] Figure 8 The structure of the vibration system in the embodiment of the present invention is shown in FIG. Figure 2 ;

[0026] In the figure: 1. Fixing system; 11. Fixed support; 12. Adapter plate; 13. Guide rail mounting base; 14. Spring spacer plate; 15. First spring support; 16. Upper limit block; 17. Guide rail; 18. Lower limit block; 2. Vibration system; 21. H-shaped support structure; 22. Slider mounting plate; 23. Second spring support; 24. Test cylinder; 25. Spring; 26. Slider; 27. Beam; 3. Wave flow circulation water tank. DETAILED DESCRIPTION

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] When ocean currents flow through marine engineering structures, alternating vortex shedding will occur behind the structures. The alternating shedding of vortices will cause the structures to be subjected to periodically changing hydrodynamic forces, thereby triggering flow-induced vibrations of the structures. Flow-induced vibration power generation has the advantage of a low starting flow velocity, making it a relatively suitable method for utilizing ocean current energy in low-flow environments. Considering that ocean currents have shear flow characteristics, the flow velocity is higher near the water surface and decays rapidly with increasing depth. In order to fully utilize ocean current energy, flow-induced vibration power generation devices should be arranged close to the water surface. At this time, the influence of surface waves cannot be ignored. Therefore, considering the wave-current coupling effect is a key and difficult issue that cannot be avoided in the technology of efficient utilization of flow-induced vibration.

[0029] The Chinese invention patent prior art with publication number CN118500666A discloses a dual-degree-of-freedom cylindrical vortex-induced vibration experimental system, including a circulating water tank (forming water flow to simulate the ocean water environment), a cylindrical vortex-induced vibration system (including a cylindrical model to simulate an ocean pipeline. During the experiment, the cylinder is in the water tank, with the axis perpendicular to the direction of the water flow and can move up and down and along the direction of the water flow) and a detection system (to detect the cylindrical model data).

[0030] Chinese invention patent publication number CN104048810A discloses a rigid cylindrical vortex-induced vibration test apparatus capable of achieving nonlinear boundary conditions. The apparatus comprises a nonlinear spring, a vertical restraint mechanism, a cylindrical model, a support, a fixture, a support frame, and a data acquisition and analysis processing unit. The vertical restraint mechanism, comprised of multiple components, forms a system with the support and nonlinear spring. The apparatus can be used in related tests to simulate the vortex-induced vibration mechanism under nonlinear stiffness.

[0031] However, the cylindrical flow-induced vibration test devices disclosed in the above two prior arts are only for testing vertical cylinders under pure flow, and do not meet the requirements of horizontal cylindrical flow-induced vibration response tests under wave-current coupling conditions. In view of the problems that existing vibration response devices are only applicable to vertical cylinders and pure flow conditions, the embodiments of the present invention propose a test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions. The device uses spring suspension to make the cylinder stationary at the initial position, and the spring serves as an elastic support for the flow-induced vibration of the cylinder. By adjusting the spring suspension position, the device can achieve the initial state of the cylinder stationary at the same position under different spring stiffness and damping coefficient. Through the test of the device in a wave-current circulation water tank, the mechanism of the action of waves on the flow-induced vibration of the cylinder can be explored, and then the influence of system parameter changes on the flow-induced vibration of the cylinder under wave-current coupling conditions can be explored, providing data support for the intelligent parameter control of the flow-induced vibration power generation device under wave-current coupling conditions.

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Reference Figures 1 to 8 As shown, the present invention provides a horizontal cylindrical flow-induced vibration response test device under wave-current coupling conditions. The test device is designed based on the size of the wave-current circulation water tank. The device includes a fixing system 1 and a vibration system 2. The fixing system 1 fixes the entire device on the wave-current circulation water tank 3 through a fixed support 11 and an adapter plate 12, while the vibration system 2 is connected to the fixing system 1 through an H-shaped support structure 21 and a slider mounting plate 22, and the movement of the vibration system 2 is achieved by sliding the slider 26 on the guide rail 17.

[0034] Specifically, the fixing system 1 includes two fixed supports 11 for fixing the entire test device on the upper wall of the wave flow circulation water tank 3. The two fixed supports 11 serve as a support base to ensure the stability of the test device during the test. An adapter plate 12 is fixed between the two fixed supports 11, and the adapter plate 12 is used to fix the guide rail mounting base 13. Two triangular support adapters are installed facing each other to form a fixed support 11. The adapter plate 12 is clamped between the four triangular support adapters and fixed by screws. The lower end of the guide rail mounting base 13 is fixed to the middle of the adapter plate 12 by screws to ensure the stability of the upper part of the device during the test. A spring spacer plate 14 is mounted on each side of the upper end of the guide rail mounting base 13. A first spring support 15 is mounted on each of the two spring spacer plates 14. The first spring support 15 corresponds to the second spring support 23 in the vibration system 2, and cooperates with each other to mount the spring 25. The position of the first spring support 15 on the spring spacer plate 14 can be adjusted as needed. The upper end of the spring 25 is suspended from the fixed pin of the first spring support 15, and the lower end of the spring 25 is suspended from the second spring support 23. Guide rails 17 are mounted in the middle and lower portions of both sides of the guide rail mounting base 13. Limit blocks are installed at the upper and lower ends of the guide rails 17 to prevent excessive displacement and sliding off the guide rails 17.

[0035] The vibration system 2 mainly includes a slider mounting plate 22, an H-shaped support structure 21, a spring 25, a test cylinder 24, etc. The H-shaped support structure 21 serves as the main support structure of the vibration system 2. The slider mounting plate 22 is fixedly mounted on the upper end, and the test cylinder 24 is mounted on the lower end. The slider mounting plate 22 is used to fix the lower end of the spring 25 and is slidably connected to the guide rail mounting base 13. Two second spring supports 23 are fixedly mounted on the front of the slider mounting plate 22. The two second spring supports 23 correspond one-to-one to the two first spring supports 15. The lower end of the spring 25 is connected to the fixed pin shaft of the second spring support 23. Two sliders 26 on the left and right are fixedly mounted on the back of the slider mounting plate 22. The sliders 26 on both sides slide with the two guide rails 17 respectively, thereby realizing the sliding connection between the slider mounting plate 22 and the guide rail 17 mounting plate. The test cylinder 24 is mounted on the lower end of the H-shaped support structure 21. The test cylinder 24 is used to simulate a marine engineering structure.

[0036] In an optional embodiment, the test cylinder 24 can be detachably mounted on the lower end of the H-shaped support structure 21. The test cylinder 24 can be replaced according to test needs to simulate different marine engineering structures, and vibration response tests can be performed on different test cylinders 24. The equipment has a wide range of applicability.

[0037] In an optional embodiment, in order to reduce the interference of the support mechanism on the test and reduce errors, the crossbeam 27 of the H-shaped support structure 21 is set at the upper part thereof and ensured that the crossbeam 27 is above the water surface.

[0038] As can be seen from the above structure, the H-shaped support structure 21, the slider mounting plate 22 and the slider 26 mounted thereon, the second spring support 23, and the test cylinder 24 are suspended on the fixing system 1 of the test device through the spring 25 as a vibrating whole.

[0039] The working principle of the embodiment of the present invention is as follows:

[0040] The apparatus for testing the flow-induced vibration response of a horizontal cylinder under wave-current coupling conditions disclosed in the present invention can perform vibration response tests on a test cylinder 24 under three different working conditions: pure wave, pure flow, and wave-current coupling, to analyze the mechanism of wave action on flow-induced vibration. In the initial state, by adjusting parameters such as the stiffness coefficient of spring 25, the upper suspension point of spring 25, and the length of spring 25, the gravity acting on the entire vibration system 2 is equal to the sum of the buoyancy and the tension of spring 25, and the test cylinder 24 is ensured to remain stationary in a predetermined position. When the fluid acts on the test cylinder 24, the test cylinder 24 is subjected to a vertical force that drives the entire vibration system 2 to vibrate. At this time, the total mass of the vibration system 2 is equivalent to the mass of the test cylinder 24. By adjusting the upper suspension point of spring 25, it is ensured that the test cylinder 24 can remain stationary in the same position under suspension conditions with different stiffness coefficients and damping coefficients of the vibration system 2.

[0041] Any details not provided in the present invention are all conventional technical means well known to those skilled in the art.

[0042] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0043] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions, characterized in that: The invention comprises a fixing system (1) and a vibration system (2); the fixing system (1) comprises a fixing support (11) fixedly connected to the top of both sides of the wave flow circulation water tank (3); an adapter plate (12) is fixedly connected between the two fixing supports (11); a vertical guide rail mounting base plate (13) is installed on the adapter plate (12); the vibration system (2) comprises a slider mounting plate (22) vertically sliding on one side of the guide rail mounting base plate (13); an elastic connecting member is further provided between the slider mounting plate (22) and the top of the guide rail mounting base plate (13); the elastic connecting member is a spring (25) connected between the guide rail mounting base plate (13) and the slider mounting plate (22); two groups of the springs (25) are provided; an H-shaped support structure is connected below the slider mounting plate (22); the H-shaped support structure is close to the slider mounting plate (22). The position of the block mounting plate (22) is connected with a crossbeam (27), one end of the H-shaped support structure away from the slider mounting plate (22) extends into the wave circulation water tank (3) and is connected to the test cylinder (24), and the test cylinder (24) is arranged horizontally; the test cylinder (24) is detachably connected to the bottom end of the H-shaped support structure, and the gravity and volume of the test cylinder (24) are adjustable; the guide rail mounting base plate (13) and the slider mounting plate (22) are respectively connected with a first spring support (15) and a second spring support (23), and the two ends of the spring (25) are connected to the first spring support (15) and the second spring support (23); a spring pad (14) is installed on the guide rail mounting base plate (13), and the first spring support (15) is adjustably installed on the spring pad (14).

2. The horizontal cylindrical flow-induced vibration response test device under wave-current coupling conditions according to claim 1 is characterized in that: Two guide rails (17) are provided on the surface of the guide rail mounting base plate (13) facing the slider mounting plate (22), and two sliders (26) are correspondingly provided on the slider mounting plate (22). The two sliders (26) are slidably matched with the two guide rails (17).

3. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 2 is characterized in that: An upper limit block (16) and a lower limit block (18) are respectively provided at the upper and lower ends of the guide rail (17).

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