Horizontal cylindrical flow-induced vibration response test device under wave-flow coupling condition

Abstract

The invention discloses a horizontal cylindrical flow-induced vibration response test device under a wave-flow coupling condition, which relates to the technical field of fluid mechanics experiments and comprises a fixing system and a vibration system. The fixing system comprises fixing supports fixedly connected to the tops of the two sides of the wave current circulating water tank, an adapter plate is fixedly connected between the two fixing supports, and a vertical guide rail mounting bottom plate is mounted on the adapter plate; the vibration system comprises a sliding block mounting plate vertically sliding on one side of the guide rail mounting bottom plate, an elastic connecting piece is further arranged between the sliding block mounting plate and the top of the guide rail mounting bottom plate, an H-shaped supporting structure is connected to the lower portion of the sliding block mounting plate, and the end, away from the sliding block mounting plate, of the H-shaped supporting structure extends into the wave current circulating water tank and is connected with a testing cylinder. And the testing cylinder is horizontally arranged. According to the invention, the defect that a traditional test device cannot be suitable for the horizontal test cylinder and the wave-current coupling working condition is overcome, and the vibration response test of the horizontal test cylinder under three different working conditions of pure flow, pure wave and wave-current coupling can be met.

Description

Technical Field

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

[0002] There are various ways to develop ocean current energy, among which flow-induced vibration power generation is particularly suitable for low flow rate environments because of its low starting flow rate. However, when the ocean current flows through the marine engineering structure, it will produce alternating vortex shedding behind the structure, causing the structure to be subjected to periodic hydrodynamic forces, triggering flow-induced vibration of the structure. This flow-induced vibration power generation method has the advantage of low starting flow rate and is suitable for the utilization of ocean current energy in low flow rate environments.

[0004] Ocean currents have shear flow characteristics, with a higher velocity near the water surface and a rapid decay as the depth increases. Therefore, in order to fully utilize ocean current energy, flow-induced vibration power generation devices should be arranged close to the water surface, and the influence of surface waves cannot be ignored. The wave-current coupling effect is an unavoidable key and difficult problem in the efficient utilization of flow-induced vibration technology.

[0005] However, the existing cylindrical flow-induced vibration test devices are mainly used for testing 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.

[0006] 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

[0007] The purpose of the present invention is to provide a test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions to solve the above-mentioned technical problems existing in the prior art.

[0008] To achieve the above-mentioned purpose, the present invention provides the following scheme: a horizontal cylindrical flow-induced vibration response test device 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 also arranged between the slider mounting plate and the top of the guide rail mounting base plate, an H-shaped supporting structure is connected to the bottom of the slider mounting plate, an end of the H-shaped supporting structure away from the slider mounting plate extends into the wave-current circulation water tank and is connected to the test cylinder, and the test cylinder is arranged horizontally.

[0009] Optionally, the test cylinder is detachably connected to the bottom end of the H-shaped support structure.

[0010] Optionally, the gravity and volume of the test cylinder are adjustable.

[0011] Optionally, a crossbeam is connected to the H-shaped support structure near the slider mounting plate.

[0012] Optionally, the elastic connecting member is a spring connected between the guide rail mounting base plate and the slider mounting plate.

[0013] Optionally, a first spring support and a second spring support are respectively connected to the guide rail mounting base plate and the slider mounting plate, and two ends of the spring are connected to the first spring support and the second spring support.

[0014] Optionally, a spring raising plate is installed on the guide rail mounting base plate, and the first spring support is installed on the spring raising plate in an adjustable position.

[0015] Optionally, the springs are provided in two groups.

[0016] Optionally, two guide rails are arranged on the surface of the guide rail mounting base plate facing the slider mounting plate, and two sliders are correspondingly arranged on the slider mounting plate, and the two sliders are slidably matched with the two guide rails.

[0017] Optionally, upper and lower ends of the guide rail are respectively provided with an upper limit block and a lower limit block.

[0018] Compared with the prior art, the present invention at least discloses the following beneficial effects:

[0019] 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-current coupling conditions. It can meet the vibration response tests of horizontal test cylinders under three different conditions: pure flow, pure wave, and wave-current coupling, and has wide applicability.

[0020] 2. The present invention ingeniously utilizes the difference between the gravity and buoyancy of the test cylinder to balance the test cylinder with a spring, so that the test cylinder is initially stationary at a predetermined water depth.

[0021] 3. The present invention can adjust the spring stiffness coefficient and the damping coefficient, and adjust the spring suspension point to ensure that the cylinder is initially stationary at the same position under different spring parameters.

[0022] 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.

[0023] 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

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. 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 creative work.

[0025] Figure 1 This is a front view of an embodiment of the present invention installed on a wave flow circulation water tank;

[0026] Figure 2 This is an axonometric view of an embodiment of the present invention installed on a wave flow circulation water tank;

[0027] Figure 3 for Figure 2 A partial enlarged view of the middle A;

[0028] Figure 4 It is a front view of an embodiment of the present invention;

[0029] Figure 5 is an axonometric diagram of an embodiment of the present invention;

[0030] Figure 6 It is a structural schematic diagram of a fixing system in an embodiment of the present invention;

[0031] Figure 7 The structure of the vibration system in the embodiment of the present invention is shown in FIG. Figure 1 ;

[0032] Figure 8 The structure of the vibration system in the embodiment of the present invention is shown in FIG. Figure 2 ;

[0033] In the figure: 1. Fixing system; 11. Fixed support; 12. Adapter plate; 13. Guide rail mounting base plate; 14. Spring pad 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

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0035] When the ocean current flows through the marine engineering structure, alternating vortex shedding will occur behind the structure. The alternating shedding of the vortex will cause the structure to be subjected to periodically changing hydrodynamic forces, thereby inducing flow-induced vibration of the structure. Flow-induced vibration power generation has the advantage of low starting flow velocity, and is a relatively suitable way of utilizing ocean current energy in low flow velocity environments. Considering that the ocean current has the characteristics of shear flow, the flow velocity is larger near the water surface, and it will decay rapidly with increasing depth. In order to fully utilize the ocean current energy, the flow-induced vibration power generation device 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 an unavoidable key and difficult problem in the technology of efficient utilization of flow-induced vibration.

[0036] 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 marine water environment), a cylindrical vortex-induced vibration system (including a cylindrical model to simulate the marine pipeline. During the experiment, the cylinder is in the water tank, with the axis perpendicular to the water flow direction and can move up and down and along the water flow direction) and a detection system (to detect the cylindrical model data).

[0037] The prior art of the Chinese invention patent with publication number CN104048810A discloses a rigid cylindrical vortex-induced vibration test device that can realize nonlinear boundary conditions, including a nonlinear spring, a vertical constraint mechanism, a cylindrical model, a support, a fixture and a support frame, and a data acquisition and analysis processing part. The vertical constraint mechanism is composed of multiple components, which form a system with the support and the nonlinear spring. The device can be used for related tests to simulate the vortex-induced vibration mechanism under nonlinear stiffness.

[0038] 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 the 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 makes the cylinder stationary in the initial position through spring suspension, and the spring serves as an elastic support for the flow-induced vibration of the cylinder. The device adjusts the spring suspension position to achieve the cylinder being stationary in the same position in the initial state under different spring stiffnesses and damping coefficients. Through the test of the device in a wave-current circulating water tank, the mechanism of action of waves on cylindrical flow-induced vibration can be explored, and then the influence of system parameter changes on cylindrical flow-induced vibration under wave-current coupling conditions can be explored, providing data support for the intelligent parameter control of flow-induced vibration power generation devices under wave-current coupling conditions.

[0039] 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.

[0040] 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, and the vibration system 2 is connected to the fixing system 1 through an H-shaped support structure 21 and a slider mounting plate 22. The slider 26 slides on the guide rail 17 to realize the movement of the vibration system 2.

[0041] 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 plate 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 plate 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 pad 14 is installed on the left and right sides of the upper end of the guide rail installation base plate 13, and the first spring support 15 is installed on the two spring pads 14 respectively. The first spring support 15 and the second spring support 23 in the vibration system 2 are arranged correspondingly up and down, and cooperate with each other to install the spring 25. The first spring support 15 can adjust its position on the spring pad 14 as needed. The upper end of the spring 25 is suspended on the fixed pin of the first spring support 15, and the lower end of the spring 25 is suspended on the second spring support 23. Guide rails 17 are installed in the middle and lower parts of both sides of the guide rail installation base plate 13, and limit blocks are installed at the upper and lower ends of the guide rail 17 to prevent excessive displacement from sliding out of the guide rail 17.

[0042] 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 is the main support structure of the vibration system 2, with the slider mounting plate 22 fixedly mounted on the upper end and the test cylinder 24 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 with the guide rail mounting base plate 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 to the two first spring supports 15 one by one. The lower end of the spring 25 is connected to the fixed pin 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 are respectively slidably matched with the two guide rails 17, thereby realizing the sliding connection between the slider mounting plate 22 and the guide rail 17 mounting plate. The test cylinder 24 is installed on the lower end of the H-shaped support structure 21, and the test cylinder 24 is used to simulate a marine engineering structure.

[0043] In an optional embodiment, the test cylinder 24 can be detachably installed at 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.

[0044] In an optional embodiment, in order to reduce the interference of the supporting mechanism on the test and reduce errors, the cross beam 27 of the H-shaped supporting structure 21 is arranged at the upper part thereof and ensures that the cross beam 27 is above the water surface.

[0045] It can be seen from the above structure that 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.

[0046] The working principle of the embodiment of the present invention is as follows:

[0047] The horizontal cylindrical flow-induced vibration response test device under wave-current coupling conditions disclosed in the present invention can perform vibration response tests on the test cylinder 24 under three different working conditions: pure wave, pure flow, and wave-current coupling, and analyze the mechanism of action of waves on flow-induced vibration. In the initial state, by adjusting the parameters such as the stiffness coefficient of the spring 25, the upper end suspension point of the spring 25, and the length of the spring 25, the gravity exerted on the entire vibration system 2 is equal to the sum of the buoyancy and the tension of the spring 25, and the test cylinder 24 is ensured to be stationary at a predetermined position. When the fluid acts on the test cylinder 24, the test cylinder 24 is subjected to the vertical force to drive 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 end suspension point of the spring 25, it is ensured that the test cylinder 24 can remain stationary at the same position under the suspension conditions of the vibration system 2 with different stiffness coefficients and damping coefficients.

[0048] The details not described in detail in the present invention are all conventional technical means well known to those skilled in the art.

[0049] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0050] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined 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 a 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 also arranged between the slider mounting plate (22) and the top of the guide rail mounting base plate (13); an H-shaped supporting structure is connected below the slider mounting plate (22); one end of the H-shaped supporting structure away from the slider mounting plate (22) extends into the wave-flow circulation water tank (3) and is connected to a test cylinder (24); the test cylinder (24) is arranged horizontally.

2. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 1 is characterized in that: The test cylinder (24) is detachably connected to the bottom end of the H-shaped support structure.

3. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 2 is characterized in that: The gravity and volume of the test cylinder (24) are adjustable.

4. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 1 is characterized in that: A crossbeam (27) is connected to the H-shaped support structure at a position close to the slider mounting plate (22).

5. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 1 is characterized in that: The elastic connecting member is a spring (25) connected between the guide rail mounting base plate (13) and the slider mounting plate (22).

6. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 5 is characterized in that: The guide rail mounting base plate (13) and the slider mounting plate (22) are respectively connected to a first spring support (15) and a second spring support (23); two ends of the spring (25) are connected to the first spring support (15) and the second spring support (23).

7. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 6 is characterized in that: A spring raising plate (14) is installed on the guide rail installation base plate (13), and the first spring support (15) is installed on the spring raising plate (14) in an adjustable position.

8. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 5, 6 or 7, characterized in that: The springs (25) are provided in two groups.

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

10. The test device for horizontal cylindrical flow-induced vibration response under wave-current coupling conditions according to claim 9, characterized in that: An upper limit block (16) and a lower limit block (18) are respectively arranged at the upper and lower ends of the guide rail (17).

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