Round tube structure eddy current suppression device and method

Abstract

The invention belongs to the technical field of eddy current suppression devices, and provides a circular tube structure eddy current suppression device and method, and the circular tube structure eddy current suppression device comprises an incident flow section and an empennage section which are connected with each other; the vortex suppression device is directly arranged on the circular pipe structure in a sleeving mode through a through hole formed in the incident flow section, and it can be guaranteed that the incident flow section and the empennage section change along with the change of the water flow direction. Through the honeycomb structure arranged in the tail wing section, the whole vortex suppression device floats in seawater, the position of the vortex suppression device in the axial direction of the circular tube structure can be changed along with lifting of the seawater horizontal plane, and it is guaranteed that the vortex suppression device is located at the seawater horizontal plane; the phenomenon that seawater submerges the vortex suppression device or the seawater plane is separated from the vortex suppression device is avoided; meanwhile, the vertical sectional area of the empennage section in the water flow direction is gradually reduced, the problem that the action degree of seawater on the rear end of the vortex suppression device is increased is solved on the basis of vortex suppression, and damage to the vortex suppression device and the circular tube structure is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of vortex suppression devices, and particularly relates to a vortex suppression device and method for a circular pipe structure. BACKGROUND

[0002] Offshore wind power, offshore oil and gas fixed platforms, nearshore wharfs, and pile foundations of sea-crossing bridges all use a large number of circular pipe structures. When seawater flows through the circular pipe structure, laminar flow will fall off the back side of the circular pipe structure, forming a vortex. The vortex will generate a transverse force on the circular pipe structure. When the frequency of vortex shedding is close to the natural frequency of the circular pipe structure, resonance will occur, causing fatigue damage to the circular pipe structure. At present, the main way to suppress vortex-induced vibration is to control the natural frequency of the structure to avoid the vortex shedding frequency, and a small number of structures use vortex suppression devices.

[0003] Traditional vortex suppression devices need to be arranged on the circular pipe structure by means of bearings and other components rotating in different directions of seawater. The working area of the vortex suppression device in the axial direction of the circular pipe structure is fixed. When the seawater level rises and falls greatly, the phenomenon of seawater submerging the vortex suppression device or the seawater level separating from the vortex suppression device will occur, which cannot meet the vortex suppression requirements. In addition, the rear end of the vortex suppression device for the circular pipe structure has a structure in which the cross section first decreases and then increases. During the process of seawater flowing from the position with a smaller cross section to the position with a larger cross section, the action area of seawater on the entire vortex suppression device increases, so that the degree of action of seawater on the vortex suppression device and the circular pipe structure increases, causing fatigue damage. SUMMARY

[0004] To solve the above problems, the present application provides a vortex suppression device and method for a circular pipe structure. The vortex suppression device is directly sleeved on the circular pipe structure through a through hole, which can ensure that the flow-approaching section and the tail wing section change with the direction of water flow. The honeycomb structure arranged inside the tail wing section makes the entire vortex suppression device float in seawater, which can change the position of the vortex suppression device in the axial direction of the circular pipe structure with the rise and fall of the seawater level, ensure that the vortex suppression device is located at the seawater level, and avoid the phenomenon of seawater submerging the vortex suppression device or the seawater level separating from the vortex suppression device. At the same time, the vertical cross-sectional area of the tail wing section gradually decreases along the direction of water flow, which avoids the increase of the degree of action of seawater on the rear end of the vortex suppression device on the basis of suppressing vortex, and reduces the damage to the vortex suppression device and the circular pipe structure.

[0005] To achieve the above purpose, in a first aspect, the present application provides a vortex suppression device for a circular pipe structure, which adopts the following technical scheme: A vortex suppression device for a circular pipe structure, comprising a flow-approaching section and a tail wing section connected to each other. The inlet section is provided with a through hole capable of being sleeved on the circular pipe structure; the tail section is internally provided with a honeycomb structure, which enables the whole vortex suppression device to float in seawater. The tail section gradually decreases in vertical cross-sectional area along the water flow direction.

[0006] Further, the inlet section comprises an arc-shaped head, first arc-shaped sections arranged on both sides of the arc-shaped head, and a second arc-shaped section connected with the first arc-shaped sections; the arc-shaped head disperses water flow to both sides of the vortex suppression device.

[0007] Further, the vortex suppression device gradually increases in vertical cross-sectional area along the water flow direction, guiding water flow to continue flowing away from the circular pipe structure.

[0008] Further, the second arc-shaped section has a larger radius of curvature than the first arc-shaped section.

[0009] Further, the tail section comprises a third arc-shaped section connected with the second arc-shaped section, a fourth arc-shaped section connected with the third arc-shaped section, and a tail connected with the fourth arc-shaped section; the length of the tail section along the water flow direction is greater than the length of the inlet section along the water flow direction.

[0010] Further, the third arc-shaped section has a larger radius of curvature than the fourth arc-shaped section.

[0011] Further, the length of the fourth arc-shaped section along the water flow direction is greater than the length of the third arc-shaped section along the water flow direction.

[0012] Further, the diameter of the through hole is smaller than the outer diameter of the circular pipe structure.

[0013] Further, the length of the vortex suppression device is determined according to the diameter of the circular pipe structure and the seawater flow rate: ; ; ; wherein, L is the length of the vortex suppression device; is a dimensionless coefficient; is the seawater flow rate; D is the pipe diameter of the circular pipe structure; is the fluid density; is the dynamic viscosity.

[0014] To achieve the above-mentioned purpose, in a second aspect, the present application further provides a circular pipe structure vortex suppression method, which adopts the following technical scheme: A vortex suppression method for a circular pipe structure uses a vortex suppression device for a circular pipe structure as described in the first aspect, and includes: water flow sequentially passing through the flow-approaching section and the tail section, guiding the water flow to pass through the surface of the vortex suppression device to avoid vortex-induced vibration.

[0015] Compared with the prior art, the vortex suppression device has the following advantages: 1、In the vortex suppression device, the through hole arranged at the flow-approaching section is directly sleeved on the circular pipe structure, which can ensure that the flow-approaching section and the tail section change with the change of the water flow direction; the honeycomb structure arranged in the tail section makes the entire vortex suppression device float in seawater, which can change the position of the vortex suppression device in the axial direction of the circular pipe structure with the change of the sea level, ensure that the vortex suppression device is located at the sea level, avoid the phenomenon that the vortex suppression device is submerged in seawater or the sea level is separated from the vortex suppression device; at the same time, the vertical cross-sectional area of the tail section along the water flow direction gradually decreases, which realizes the purpose of suppressing vortex and avoids the problem that the degree of action of seawater on the rear end of the vortex suppression device increases, thereby reducing the damage to the vortex suppression device and the circular pipe structure.

[0016] 2、In the vortex suppression device, the arc-shaped head is used to first contact the water flow and disperse the water flow to both sides of the vortex suppression device, the arc-shaped head can reduce the water flow impact when the water flow direction is changed; the first arc-shaped section is arranged to gradually increase the vertical cross-sectional area of the vortex suppression device along the water flow direction, and guide the water flow to continue flowing away from the circular pipe structure; the curvature radius of the second arc-shaped section is greater than that of the first arc-shaped section, so that the water flow away from the circular pipe structure direction tends to be gentle to transition to the tail section.

[0017] 3、In the vortex suppression device, the length of the tail section along the water flow direction is greater than the length of the flow-approaching section along the water flow direction, which ensures the degree of action of the water flow on the side surface of the tail section, and ensures that the flow-approaching section always faces the water flow direction and belongs to passive steering without the need for additional power to adjust.

[0018] 4、In the vortex suppression device, the curvature radius of the third arc-shaped section is greater than that of the fourth arc-shaped section, so that the water flow away from the circular pipe structure direction is gently transitioned to the fourth arc-shaped section.

[0019] 5、In the vortex suppression device, the length of the fourth arc-shaped section along the water flow direction is greater than the length of the third arc-shaped section along the water flow direction, so that the water flow on both sides can smoothly gather at the tail section, the adhesion degree of the water flow to the vortex suppression device can be ensured, and the vortex suppression effect is ensured.

[0020] 6. In the present invention, the coordination of the arc-shaped head, the first arc-shaped segment, the second arc-shaped segment, the third arc-shaped segment and the fourth arc-shaped segment avoids the generation and shedding of vortices, thereby avoiding the occurrence of vortex-induced vibration and reducing the force of the ocean current; the upstream segment can guide the water flow to both sides of the vortex suppression device without excessive water flow; the tail wing segment can ensure that the water flow smoothly transitions to the fourth arc-shaped segment, and enables the water flow on both sides to smoothly gather to the tail, thereby ensuring the vortex suppression effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings constituting a part of the specification of this embodiment are used to provide a further understanding of this embodiment. The schematic embodiments and descriptions of this embodiment are used to explain this embodiment and do not constitute an improper limitation on this embodiment.

[0022] Figure 1 Schematic diagram of the structure of the eddy current suppression device according to embodiment 1 of the present invention; Figure 2 Schematic cross-sectional view of the eddy current suppression device according to Example 1 of the present invention; Among them, 1. vortex suppression device; 101. oncoming section; 1011. arc-shaped head; 1012. first arc-shaped segment; 1013. second arc-shaped segment; 102. tail section; 1021. third arc-shaped segment; 1022. fourth arc-shaped segment; 1023. tail; 103. through hole; 104. honeycomb structure; 105. skin; 106. connecting part; 2. circular tube structure. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0025] Example 1: like Figure 1 and Figure 2 As shown, this embodiment provides a circular tube structure vortex suppression device that can prevent vortices generated when ocean currents flow through the circular tube structure, thereby preventing vortex-induced vibrations and ensuring structural safety. This device requires no structural adjustments, controls the natural frequency of the rods, and avoids the influence of structural design. Furthermore, it is a passive device that does not consume additional energy, offering low cost, easy installation, and excellent results.

[0026] The vortex suppression device 1 has a streamlined structure on the outside, which can guide the water flow to flow evenly and stably through the surface, avoid the generation and shedding of vortices, and further avoid the occurrence of vortex-induced vibrations, thereby reducing the force of the ocean current. The vortex suppression device 1 includes a headstream section 101, a tail section 102 interconnected with the headstream section 101, a through hole 103 provided at the headstream section 101, a honeycomb structure 104 provided in the tail section 102, and a skin 105 provided outside the honeycomb structure 104; the through hole 103 can be set as an expandable mechanism through a connector 106, so as to be conveniently sleeved on the circular tube structure 2. The vortex suppression device 1 is symmetrical along the center, with the same flow velocity on both sides, and will not generate a lateral lift effect.

[0027] The incoming flow section 101 includes an arc-shaped head 1011, a first arc-shaped segment 1012 arranged on both sides of the arc-shaped head 1011, and a second arc-shaped segment 1013 connected to the first arc-shaped segment 1012. Specifically, the arc-shaped head 1011 is used to first contact the water flow and disperse the water flow to both sides of the vortex suppression device 1. The setting of the arc-shaped head 1011 can reduce the impact of the water flow when changing the direction of the water flow; the setting of the first arc-shaped segment 1012 makes the vertical cross-sectional area of ​​the vortex suppression device 1 in the direction of the water flow gradually increase, guiding the water flow to continue to flow in the direction away from the circular tube structure 2; the second arc-shaped segment 1013 is a transition section between the incoming flow section 101 and the tail section 102. The curvature radius of the second arc-shaped segment 1013 is greater than the curvature radius of the first arc-shaped segment 1012, so that the water flow away from the circular tube structure 2 tends to be smooth and transitions to the tail section 102.

[0028] The cooperation between the arc-shaped head 1011, the first arc-shaped segment 1012 and the second arc-shaped segment 1013 can guide the water flow to both sides of the vortex suppression device 1 while avoiding excessive water flow, and can ensure that the water flow is smoothly guided to the tail wing section 102, thereby ensuring the vortex suppression effect.

[0029] The tail section 102 includes a third arc segment 1021 connected to the second arc segment 1013 , a fourth arc segment 1022 connected to the third arc segment 1021 , and a tail portion 1023 connected to the fourth arc segment 1022 .

[0030] The length of the tail section 102 along the water flow direction is greater than the length of the incoming flow section 101 along the water flow direction, ensuring the extent of the water flow's effect on the side of the tail section 102, so as to ensure that the incoming flow section 101 always faces the water flow direction. This is passive steering and does not require additional power for adjustment.

[0031] The curvature radius of the third arc segment 1021 is greater than that of the fourth arc segment 1022, so that the water flow direction away from the circular tube structure 2 is smoothly transitioned to the fourth arc segment 1022.

[0032] The length of the fourth arc segment 1022 along the water flow direction is greater than that of the third arc segment 1021 along the water flow direction, so that the water flow on both sides can be smoothly gathered to the tail 1023, and the degree of fit between the water flow and the vortex suppression device 1 can be ensured, and the vortex suppression effect is ensured.

[0033] The cooperation of the arc head 1011, the first arc segment 1012, the second arc segment 1013, the third arc segment 1021 and the fourth arc segment 1022 avoids the generation and shedding of vortexes, and further avoids the occurrence of vortex-induced vibration and reduces the sea current force; in the flow-approaching segment 101, the water flow can be guided to both sides of the vortex suppression device 1 under the condition of avoiding excessive water flow, and in the tail wing segment 102, the water flow can be smoothly transitioned to the fourth arc segment 1022, and the water flow on both sides can be smoothly gathered to the tail 1023, and the vortex suppression effect is ensured.

[0034] The diameter of the through hole 103 is smaller than the outer diameter of the circular tube structure 2, so that the vortex suppression device 1 can freely rotate around the circular tube structure 2, and the flow-approaching segment 101 corresponds to the water flow direction.

[0035] In other embodiments, in order to reduce the difficulty of sleeving on the circular tube structure 2, an openable movable part is arranged at the flow-approaching segment 101, one side of the movable part is hinged to the flow-approaching segment 101 through a hinge, and the other side is connected through a connecting piece 106, which can be unlocked and loosened by using buckles, bolt connecting pieces or other locking components; specifically, when sleeving, the movable part is opened, the circular tube structure 2 is placed in the through hole 103, and then the movable part is combined and locked.

[0036] A honeycomb structure 104 is arranged in the tail wing segment 102 to reduce the overall weight, so that the vortex suppression device 1 can float on the sea water and can rise and fall with the sea water, avoiding the phenomenon that the sea water submerges the vortex suppression device or the sea level separates from the vortex suppression device.

[0037] After the honeycomb structure 104 is arranged in the tail wing segment 102, an outer skin 105 is arranged to seal and prevent the entry of sea water.

[0038] When designing the vortex suppression device 1, the density, salinity, viscosity, and flow rate of the seawater at the target application site are first measured. Based on the density of the seawater, the size of the honeycomb structure 104 is adjusted to ensure self-buoyancy, eliminating the need for additional blocking devices, reducing wear, and simplifying offshore installation.

[0039] The honeycomb structure 104 can be made of polymer materials, which have the characteristics of high strength, light weight and corrosion resistance. By adjusting the size and material composition of the honeycomb structure 104, the gravity and buoyancy of the vortex suppression device 1 can be made equal, and the device can naturally float in the water. In some embodiments, according to the total volume V of the vortex suppression device 1 总 , and seawater density ρ 海水， Calculate the total buoyancy F 浮 =V 总 *ρ 海水 By adjusting the wall thickness of the honeycomb structure 104, the overall material volume V of the eddy current suppression device 1 is 实体 =V 总 *ρ 海水 / ρ 材料 , so that the gravity and buoyancy of the vortex suppression device 1 are equal, thereby ensuring that the device has self-buoyancy.

[0040] The length of the vortex suppression device 1 is determined according to the diameter of the circular tube structure 2 and the seawater flow rate: ; ; ; in, is the length of the eddy current suppression device; is the dimensionless coefficient and the Reynolds number related; is the seawater velocity (m / s), which can be the maximum value in the historical data; is the diameter or characteristic diameter of the circular tube structure (m); is the density of the fluid (seawater) (kg / m 3 ); is the dynamic viscosity (Pa·s); Increase and flow rate The increase, As the length of the eddy current suppression device increases It also needs to be increased so that the ocean current flows smoothly through the device, delaying fluid separation and avoiding the generation of eddies.

[0041] In some embodiments, the outer shape of the flow-approaching section 101 is parabolic, with a maximum width of 1.1 times the diameter D of the circular tube; the tail section 102 is a polynomial curve, gradually reducing to the tail end, which is 0.05D wide. Suitable for Reynolds number 10 3 <Re<10 7 .

[0042] The vortex suppression device 1 in this embodiment is an external surface streamline structure that can guide water to flow uniformly and stably through the surface, avoid the generation and shedding of vortexes, and further avoid resonance of the structure, ultimately ensuring the safety of the structure; the streamline structure can effectively reduce the water flow force on the circular tube structure; the flow-approaching section 101 is provided with an openable movable part, which is simple and convenient to install; the vortex suppression device 1 naturally floats in water and has the characteristics of self-floating, making it convenient and labor-saving to install underwater without the need for large machinery assistance; the vortex suppression device 1 will rotate around the circular tube structure 2 as the water flow direction changes, always facing the flow direction, which is passive steering and does not require additional power.

[0043] Embodiment 2 This embodiment provides a vortex suppression method for a circular tube structure, which uses the vortex suppression device for a circular tube structure as described in Embodiment 1, including: water flows through the flow-approaching section and the tail section in turn, guiding the water to flow through the surface of the vortex suppression device to avoid vortex-induced vibration.

[0044] The above only describes the preferred embodiments of the present embodiment and is not intended to limit the present embodiment. For those skilled in the art, the present embodiment can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present embodiment shall be included in the protection scope of the present embodiment.

Claims

1. A circular tube structure eddy current suppression device, characterized in that: It includes the upstream section and the tail section which are connected to each other; The incoming flow section is provided with a through hole that can be sleeved on the circular tube structure; the tail section is provided with a honeycomb structure inside, and the honeycomb structure enables the entire vortex suppression device to float in the seawater; The vertical cross-sectional area of ​​the tail section gradually decreases along the water flow direction.

2. The circular tube structure eddy current suppression device according to claim 1, characterized in that: The incoming flow section includes an arc-shaped head, a first arc-shaped segment arranged on both sides of the arc-shaped head, and a second arc-shaped segment connected to the first arc-shaped segment; the arc-shaped head disperses the water flow to both sides of the vortex suppression device.

3. The circular tube structure eddy current suppression device according to claim 2, characterized in that: The vertical cross-sectional area of ​​the vortex suppression device in the water flow direction gradually increases, guiding the water flow to continue flowing in a direction away from the circular tube structure.

4. The circular tube structure eddy current suppression device according to claim 3, characterized in that: The curvature radius of the second arc segment is greater than the curvature radius of the first arc segment.

5. The circular tube structure eddy current suppression device according to claim 4, characterized in that: The tail wing section includes a third arc segment connected to the second arc segment, a fourth arc segment connected to the third arc segment, and a tail connected to the fourth arc segment; the length of the tail wing section along the water flow direction is greater than the length of the upstream section along the water flow direction.

6. The circular tube structure eddy current suppression device according to claim 5, characterized in that: The curvature radius of the third arc segment is greater than the curvature radius of the fourth arc segment.

7. The circular tube structure eddy current suppression device according to claim 6, characterized in that: The length of the fourth arc segment along the water flow direction is greater than the length of the third arc segment along the water flow direction.

8. The circular tube structure eddy current suppression device according to claim 1, characterized in that: The diameter of the through hole is smaller than the outer diameter of the circular tube structure.

9. The circular tube structure eddy current suppression device according to claim 1, characterized in that: The length of the vortex suppression device is determined according to the diameter of the circular tube structure and the seawater flow rate: ； ； ； in, is the length of the eddy current suppression device; is the dimensionless coefficient; is the seawater flow rate; D is the diameter of the circular tube structure; is the fluid density; is the dynamic viscosity.

10. A method for suppressing eddy current in a circular tube structure, characterized in that: The circular tube structure vortex suppression device according to any one of claims 1 to 9 includes: water flows through the oncoming section and the tail section in sequence, guiding the water flow through the surface of the vortex suppression device to avoid the occurrence of vortex-induced vibration.

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