Flexible transmission type bidirectional shear flow standpipe vortex-induced vibration experimental device

Abstract

The present invention provides a flexible transmission type bidirectional shear flow field riser vortex-induced vibration experimental device, comprising a deep-sea pipeline model, a large rotating gear, a power module, a base module, a tensioner module, a rigid fixing module, an inner and outer boundary elastic constraint module, a driving pulley, and a metal wire flexible belt. The deep-sea pipeline model is connected to the tensioner module and the rigid fixing module at both ends. The tensioner module and the rigid fixing module are fixed to the large rotating gear. The large rotating gear is fixed to the base module via the outer boundary elastic constraint module and the inner boundary elastic constraint module. The base module is fixed to the false bottom of the marine water tank. The power module drives the driving pulley to rotate the large rotating gear via the metal wire flexible belt, thereby simulating a bidirectional shear flow field. The present invention has a stable structure, can avoid resonance caused by the device being close to the vortex-induced vibration frequency, has a smooth transmission without jamming, and a clean flow field. It can obtain high-quality experimental test data of pipeline vortex-induced vibration under bidirectional shear flow field.

Description

Technical Field

[0001] The present invention relates to the field of marine engineering technology, in particular to a flexible transmission type bidirectional shear flow field standpipe vortex-induced vibration experimental device. Background Art

[0002] Internal waves are a typical severe ocean condition prevalent in density-stratified oceans. They are characterized by large amplitude, long duration, and nonlinearity. They generate a unique bidirectional shear flow field, which can not only cause severe shearing effects on deep-sea pipelines downstream but also induce highly complex vortex-induced vibrations (VIVs) downstream and across the flow. VIVs refer to the alternating release of vortices on either side of a columnar structure under the influence of water flow, generating periodic pulsating forces. When these pulsating forces approach a certain natural frequency of the columnar structure, they induce significant VIVs (VIVs). VIVs are a major factor in fatigue damage to marine pipelines. Currently, fundamental understanding of the VIVs of marine pipelines under the influence of internal wave-induced bidirectional shear flows is still lacking. Therefore, the development of a reliable VIV testing device for deep-sea pipelines under internal wave-induced bidirectional shear flows is crucial for studying VIVs induced by internal wave-induced bidirectional shear flows.

[0003] At present, the research on vortex-induced vibration of marine pipelines in the academic and engineering communities at home and abroad mainly relies on experimental means. However, the experimental technology for vortex-induced vibration of deep-sea pipelines under the action of internal wave secondary bidirectional shear flow is very limited. The 2018 patent provides a vortex-induced vibration test platform that can simulate the tension hamstring tendon under bidirectional shear flow. However, in general, there are still the following shortcomings: 1. The device is relatively complex and bulky, inconvenient to install, and requires a large motor power; 2. The device is unstable and the natural frequency easily falls within the significant frequency range of vortex-induced vibration, causing resonance and affecting the accuracy of the experiment; 3. The structural cantilever is very long, and there is a risk of structural instability; 4. The cantilever structure will disrupt the flow field during the operation of the device, making the created flow field less than ideal and clean, affecting the test results. Summary of the Invention

[0004] In view of the defects in the prior art, the purpose of the present invention is to provide a flexible transmission type bidirectional shear flow field standpipe vortex-induced vibration experimental device.

[0005] According to the present invention, a flexible transmission type bidirectional shear flow field riser vortex-induced vibration experimental device is provided, which includes a deep-sea pipeline model, a large rotary gear, a power module, a base module, a tensioner module, a rigid fixing module, an inner boundary elastic constraint module, an outer boundary elastic constraint module, and a driving wheel, wherein:

[0006] Both ends of the deep-sea pipeline model are connected to the tensioner module and the rigid fixing module respectively;

[0007] The tensioner module and the rigid fixing module are fastened to the large rotary gear;

[0008] The large rotary gear is fixed to the base module through an outer boundary elastic constraint module and an inner boundary elastic constraint module;

[0009] The base module is fixed to the false bottom of the marine water tank;

[0010] The power module drives the driving wheel through a metal wire flexible belt, thereby driving the large rotary gear to rotate.

[0011] Preferably, the tensioner module includes: a first clamp, a first universal joint, a first three-force sensor, a movable slider, a linear track, a long-axis screw, a screw adapter flange, a bottom fixed adapter flange, a first spring, a top plate, and a top screw, wherein:

[0012] One end of the deep-sea pipeline model is clamped and connected to a first clamp;

[0013] The first fixture, the first universal joint, and the first three-force sensor are connected in sequence;

[0014] One end of the long-axis screw is connected to the first three-force sensor;

[0015] The long-axis screw is bolted to the movable slider via the screw adapter flange;

[0016] The linear track is mounted on the bottom fixed adapter flange, and the movable slider is slidably arranged on the linear track;

[0017] The top screw is arranged at the other end of the long-axis screw and presses one end of the spring through the top plate;

[0018] The other end of the spring is in contact with and connected to the bottom fixed adapter flange.

[0019] Preferably, the rigid fixing module includes a second clamp, a second universal joint, a second three-force sensor and a base fixing flange, wherein:

[0020] The other end of the deep-sea pipeline model is connected to the second clamp;

[0021] The second fixture is bolted to the second universal joint, the second three-force sensor, and the base fixing flange in sequence;

[0022] The base fixing flange is bolted to the large rotary gear.

[0023] Preferably, the outer boundary constraint module includes a downward bearing, a bolt, a second spring and a downward flange block, wherein:

[0024] The downward pressure bearing is fixedly connected to the downward pressure flange block;

[0025] The bolt compresses the second spring, passes through the downward pressure flange block and is fixed on the base module, compresses the second spring and reacts the restoring force of the downward pressure flange block, thereby causing the downward pressure bearing to compress the large rotary gear.

[0026] Preferably, the inner boundary constraint module includes an inner top bearing, an inner top flange block, bolts, a third spring, a linear track, a slider and a first base flange, wherein:

[0027] The inner boundary constraint module bolts are tightened to compress the third spring, and the bolts are connected to the inner top flange block;

[0028] The inner top flange block is connected to the slider with bolts;

[0029] The slider moves unidirectionally on the linear track, and the linear track is fixed to the first base flange. The restoring force of the third spring reacts on the inner top flange block, thereby causing the inner top bearing to support the large rotary gear.

[0030] Preferably, the power module includes a servo motor, a reducer, an optical axis, a bearing seat, a support structure, a driving wheel and a second base flange, wherein:

[0031] The bearing seat is fixed on the supporting structure;

[0032] The supporting structure is fixed to the false bottom of the marine tank via the second base flange;

[0033] The optical axis is fixedly connected to the driving wheel;

[0034] The servo motor is connected to the optical axis via the speed reducer to drive the driving wheel to rotate.

[0035] Preferably, the outer edge of the driving wheel has a gear groove, and the driving wheel teeth are engaged with the toothed metal wire flexible belt.

[0036] Preferably, the outer edge of the large rotary gear comprises a geared groove for limiting the vertical movement of the flexible metal wire belt, and the large rotary gear is engaged with the flexible metal wire belt with gears.

[0037] Preferably, the base module supports a base, a bearing and a bearing base, wherein:

[0038] The support base is fixedly installed on the lifting false bottom of the deep water tank of the marine engineering;

[0039] The bearing is connected to the support base through the bearing base by bolts, and the top of the bearing is in contact with and connected to the lower bottom surface of the large rotary gear.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] 1. The present invention provides a test device that can stably simulate the internal wave secondary bidirectional shear flow field encountered by deep-sea pipelines by adjusting the device configuration, thereby solving the problems of existing shear flow field simulation devices such as instability, easy resonance, and frequent flow field interference.

[0042] 2. The present invention operates smoothly without meshing jamming; the device is simple, the structure is flexible, and it is easy to install;

[0043] 3. The device of the present invention is firm and has good structural stability, and will not cause structural instability caused by the overlong cantilever in traditional experimental technology.

[0044] 4. The natural frequency of the device of the present invention is significantly different from the significant period of vortex-induced vibration, and will not cause resonance.

[0045] 5. There are no auxiliary structures inside the large rotary gear of the device provided by the present invention, and the flow field is clean and ideal. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0047] Figure 1 It is a three-dimensional view of the present invention.

[0048] Figure 2 This is a schematic diagram of the tensioner module.

[0049] Figure 3 It is a schematic diagram of the rigid fixed module.

[0050] Figure 4 This is a schematic diagram of the inner boundary elastic constraint module.

[0051] Figure 5 This is a schematic diagram of the outer boundary elastic constraint module.

[0052] Figure 6 This is a three-dimensional view of the power module.

[0053] Figure 7 This is a three-dimensional view of the base module.

[0054] Figure 8 This is a three-dimensional view of the large rotating gear.

[0055] Figure 9 It is a three-dimensional view of the driving wheel.

[0056] Figure 10 It is a partial schematic diagram of a metal wire flexible belt.

[0057] In the picture:

[0058] Large rotary gear 1

[0059] Base module 2

[0060] Outer Boundary Elastic Constraint Module 3

[0061] Inner boundary elastic constraint module 4

[0062] Deepsea Pipeline Model 5

[0063] Tensioner module 6

[0064] Rigid fixing module 7

[0065] Metal wire flexible belt 8

[0066] Driving wheel 9

[0067] Power module 10

[0068] Spring 11

[0069] Long axis screw 12

[0070] Top screw 13

[0071] Top sheet 14

[0072] Bottom fixed adapter flange 15

[0073] Screw adapter flange 16

[0074] Three-point force sensor 17

[0075] Fixture 18

[0076] Universal joint 19

[0077] Linear track 20

[0078] Movable slider 21

[0079] Fixture 22

[0080] Universal joint 23

[0081] Three-point force sensor 24

[0082] Base fixing flange 25

[0083] Inner top flange block 26

[0084] Inner top bearing 27

[0085] Bolt 28

[0086] Spring 29

[0087] Slider 30

[0088] Linear track 31

[0089] Base flange 32

[0090] Down pressure bearing 33

[0091] Bolt 34

[0092] Spring 35

[0093] Press down flange block 36

[0094] Servo motor 37

[0095] Reducer 38

[0096] Support structure 39

[0097] Base flange 40

[0098] Bearing seat 41

[0099] Optical axis 42

[0100] Support base 43

[0101] Bearing base 44

[0102] Bearing 45 DETAILED DESCRIPTION

[0103] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0104] like Figure 1As shown, this embodiment includes: a deep-sea pipeline model 5, a large rotating gear 1, a power module 10, a base module 2, a tensioner module 6, a rigid fixing module 7, an inner boundary elastic constraint module 4, an outer boundary elastic constraint module 3, a driving pulley 9, and a flexible metal belt 8. The deep-sea pipeline model 5 is connected to the tensioner module 6 and the rigid fixing module 7 at both ends. The tensioner module 6 and the rigid fixing module 7 are bolted to the large rotating gear 1. The large rotating gear 1 is fixed to the base module 2 via the outer boundary elastic constraint module 3 and the inner boundary elastic constraint module 4. The base module 2 is bolted to the false bottom of the offshore water tank. The power module 10 drives the driving pulley 9 via the flexible metal belt 8, which drives the large rotating gear 1 to rotate, thereby simulating the bidirectional shear flow field generated by the internal waves experienced by the pipeline 5. The flexible transmission type bidirectional shear flow field riser vortex-induced vibration experimental device works as a whole in a deep water pool of an ocean engineering project. The bottom of the flexible transmission type bidirectional shear flow field riser vortex-induced vibration experimental device is fixed to the lifting false bottom of the ocean engineering pool in the form of bolts through the base module 2.

[0105] like Figure 2 As shown, the tensioner module 6 includes: a clamp 18, a universal joint 19, a three-force sensor 17, a movable slider 21, a linear track 20, a long-axis screw 12, a screw adapter flange 16, a bottom fixed adapter flange 15, a spring 11, a top plate 14 and a top screw 13. One end of the deep-sea pipeline model 5 is clamped and connected to the clamp 18 of the tensioner through screws; the clamp 18 is connected to one end of the universal joint 19 through a flange end plate; the other end of the universal joint 19 is bolted to the three-force sensor 17 through a flange; the three-force sensor 17 is connected to the long-axis screw 12 through a flange bolt; the long-axis screw 12 is bolted to the movable slider 21 through the screw adapter flange 16; the movable slider 21 is in contact with the linear track 20; the linear track 20 is connected to the bottom fixed adapter flange 15 through bolts; the top screw 13 presses one end of the spring 11 through the top plate 14, and the other end of the spring 11 is in contact with the bottom fixed adapter flange 15; the elastic force of the spring 11 reacts on the top plate 14, thereby transmitting the stretching of the deep-sea pipeline model 5 to provide pre-tension.

[0106] like Figure 3 As shown, the rigid fixing module 7 includes a clamp 22, a universal joint 23, a three-force sensor 24, and a base fixing flange 25. The other end of the deep-sea pipeline model 5 is connected to the clamp 22, which is bolted to the universal joint 23, the three-force sensor 24, and the base fixing flange 25 in sequence. The clamp 22 is then bolted to the large rotary gear 1 via the base fixing flange 25.

[0107] like Figure 4As shown, the inner boundary elastic constraint module 4 includes: an inner top bearing 27, an inner top flange block 26, bolts 28, a spring 29, a linear track 31, a slider 30, and a base flange 32. Tightening the bolts 28 of the inner boundary constraint module compresses the spring 29. The bolts 28 connect to the inner top flange block 26, which is bolted to the slider 30. The slider 30 can move unidirectionally on the linear track 31. The linear track 31 is fixed to the base flange 32 by bolts. The restoring force of the spring 29 reacts on the inner top flange block 26, thereby causing the inner top bearing 27 to press against the large slewing gear 1, limiting the radial movement of the large slewing gear 1.

[0108] like Figure 5 As shown, the outer boundary constraint module 3 includes a downward pressure bearing 33, a bolt 34, a spring 35, and a downward pressure flange block 36. The downward pressure bearing 33 is rigidly connected to the downward pressure flange block 36. The bolt 34 compresses the spring 35, passes through the downward pressure flange block 36, and is fixed to the base module 2. The compressed spring 35 generates a restoring force that reacts against the downward pressure flange block 36, causing the downward pressure bearing 33 to press against the large slewing gear 1, thereby limiting the vertical movement of the large slewing gear 1.

[0109] like Figure 6 As shown, the power module 10 includes a servo motor 37, a reducer 38, an optical axis 42, a bearing seat 41, a support structure 39, and a base flange 40. The bearing seat 41 is fixed to the support structure 39, which is bolted to the false bottom of the offshore tank via the base flange 40. The optical axis 42 is fixedly connected to the driving wheel 9. The servo motor 37 is connected to the optical axis 42 via the reducer 38, driving the driving wheel 9 to rotate, thereby driving the large rotary gear 1 to rotate, and ultimately driving the deep-sea pipeline model 5 to rotate, forming a relative bidirectional shear flow field with the surrounding water.

[0110] like Figure 7 As shown, the base module 2 comprises a support base 43, a bearing 45, and a bearing base 44. The support base 43 is fixed to the lifting false bottom of the marine engineering deep-water tank via high-strength bolts, enabling the flexible transmission-type bidirectional shear flow field pipeline vortex-induced vibration experimental device to operate entirely within the marine engineering deep-water tank. The bearing 45 is bolted to the support base 43 via the bearing base 44. The top of the bearing 45 contacts and connects with the lower surface of the large slewing gear 1, reducing friction and ensuring smooth rotation of the large slewing gear 1. Together with the outer boundary constraint module 3, it limits the vertical movement of the large slewing gear 1.

[0111] like Figure 8, 9, 10 show the large rotary gear 1, the driving wheel 9 and the metal flexible belt 8 respectively. The driving wheel 9 is fixed to the optical axis 42 of the power module, and drives the large rotary gear 1 to rotate through the metal flexible belt 8, and then drives the deep-sea pipeline model 5 to rotate, forming a relative bidirectional shear flow field with the surrounding water. The outer edge of the large rotary gear 1 has a gear groove, and the gear is engaged with the metal wire flexible belt 8 with a gear. The outer edge of the driving wheel 9 has a gear groove, and the driving wheel teeth are engaged with the toothed metal wire flexible belt 8. The groove of the large rotary gear 1 limits the vertical movement of the metal wire flexible belt 8.

[0112] The production and installation process of this embodiment is as follows:

[0113] Before the formal experiment, the appropriate similarity criteria, model scale ratio, and experimental conditions were selected based on the actual dimensions of the deep-sea riser, the specific test conditions, the size of the laboratory deep-water tank, and the economic feasibility of the experiment. The appropriate materials and dimensions of each module were selected based on the strength and rigidity requirements of the experimental device under the experimental conditions. After the modules of the experimental device were fabricated, the detailed installation steps were as follows:

[0114] First, 20 independent base modules were assembled and fixed to the steel lifting base of the laboratory pool, forming a circle with a diameter of 8 meters, which matches the diameter of the large slewing gear. Then, the large slewing gear was placed on the support base, and 20 outer boundary constraint modules and 20 inner boundary constraint modules were installed to secure the large slewing gear.

[0115] Next, the power module support structure is mounted on the pool's steel lifting false bottom via the base flange. The bearing housing, drive pulley, and optical shaft are assembled in sequence, followed by the reducer and servo motor. A metal flexible belt is tightly fitted into the grooves of the large slewing gear and drive pulley, completing the power system connection.

[0116] Finally, the tensioner module fixture, universal joint, three-force sensor, and long-axis screw are assembled sequentially to complete the tensioner module assembly. The module is then secured to the large slewing gear via the base flange. The rigid mounting module is assembled with the fixture, universal joint, three-force sensor, and base flange, and secured radially opposite the large slewing gear. The deep-sea pipeline model is clamped between the tensioner and rigid mounting modules.

[0117] After the overall installation of the experimental device is completed, the device is debugged. After the debugging is completed, the experimental device can be started to conduct tests according to specific working conditions and experimental technical requirements.

[0118] In the description of this application, it should be understood that the terms "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 this application and simplifying the description, 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 cannot be understood as a limitation on this application.

[0119] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A flexible transmission type bidirectional shear flow field standpipe vortex-induced vibration experimental device, characterized in that: It includes a deep-sea pipeline model, a large rotary gear, a power module, a base module, a tensioner module, a rigid fixing module, an inner boundary elastic constraint module, an outer boundary elastic constraint module, and a driving wheel, among which: Both ends of the deep-sea pipeline model are connected to the tensioner module and the rigid fixing module respectively; The tensioner module and the rigid fixing module are fastened to the large rotary gear; The large rotary gear is fixed to the base module through an outer boundary elastic constraint module and an inner boundary elastic constraint module; The base module is fixed to the false bottom of the marine water tank; The power module drives the driving wheel through a flexible metal wire belt, thereby driving the large rotary gear to rotate; The outer boundary elastic constraint module includes a downward bearing, a bolt, a second spring and a downward flange block, wherein: The downward pressure bearing is fixedly connected to the downward pressure flange block; The bolt compresses the second spring, passes through the downward pressure flange block and is fixed to the base module, compresses the second spring and reacts the restoring force of the downward pressure flange block, thereby causing the downward pressure bearing to press the large rotary gear; The inner boundary elastic constraint module includes an inner top bearing, an inner top flange block, bolts, a third spring, a second linear track, a slider and a first base flange, wherein: The inner boundary elastic constraint module is bolted tight to compress the third spring and is bolted to the inner top flange block; The inner top flange block is connected to the slider with bolts; The slider moves unidirectionally on the second linear track, the second linear track is fixed to the first base flange, and the restoring force of the third spring reacts on the inner top flange block, thereby causing the inner top bearing to support the large rotary gear; The base module includes a support base, a bearing and a bearing base, wherein: The support base is fixedly arranged on the false bottom of the marine engineering deep water tank; The bearing is connected to the support base through the bearing base by bolts, and the top of the bearing is in contact with and connected to the lower bottom surface of the large rotary gear.

2. The flexible transmission type bidirectional shear flow field standpipe vortex-induced vibration experimental device according to claim 1 is characterized in that: The tensioner module includes: a first clamp, a first universal joint, a first three-force sensor, a movable slider, a first linear track, a long-axis screw, a screw adapter flange, a bottom fixed adapter flange, a first spring, a top plate, and a top screw, wherein: One end of the deep-sea pipeline model is clamped and connected to a first clamp; The first fixture, the first universal joint, and the first three-force sensor are connected in sequence; One end of the long-axis screw is connected to the first three-force sensor; The long-axis screw is bolted to the movable slider via the screw adapter flange; The first linear track is mounted on the bottom fixed adapter flange, and the movable slider is slidably arranged on the first linear track; The top screw is arranged at the other end of the long-axis screw and presses one end of the first spring through the top plate; The other end of the first spring is in contact with and connected to the bottom fixed adapter flange.

3. The flexible transmission type bidirectional shear flow field standpipe vortex-induced vibration experimental device according to claim 1 is characterized in that: The rigid fixing module includes a second clamp, a second universal joint, a second three-force sensor, and a base fixing flange, wherein: The other end of the deep-sea pipeline model is connected to the second clamp; The second fixture is bolted to the second universal joint, the second three-force sensor, and the base fixing flange in sequence; The base fixing flange is bolted to the large rotary gear.

4. The flexible transmission type bidirectional shear flow field standpipe vortex-induced vibration experimental device according to claim 1 is characterized in that: The power module includes a servo motor, a reducer, an optical axis, a bearing seat, a support structure, a driving wheel and a second base flange, wherein: The bearing seat is fixed on the supporting structure; The supporting structure is fixed to the false bottom of the marine tank via the second base flange; The optical axis is fixedly connected to the driving wheel; The servo motor is connected to the optical axis via the speed reducer to drive the driving wheel to rotate.

5. The flexible transmission type bidirectional shear flow field standpipe vortex-induced vibration experimental device according to claim 1, characterized in that: The outer edge of the driving wheel is provided with a gear groove, and the driving wheel is engaged with a toothed metal wire flexible belt.

6. The flexible transmission type bidirectional shear flow field standpipe vortex-induced vibration experimental device according to claim 1, characterized in that: The outer edge of the large rotary gear comprises a gear groove for limiting the vertical movement of the flexible metal wire belt, and the large rotary gear is meshed with the flexible metal wire belt with teeth.

Images