Truncation model test device for bending vibration of deepwater top tensioned riser

Abstract

The invention discloses a truncation model test device for bending vibration of a deepwater top-tensioned riser, and the device comprises a frame which forms a cavity in a surrounding manner, and the cavity is communicated with the outside; each hinged support comprises a first elastic body, a shell and a spherical hinge which is arranged in the shell and provided with a first channel, the internal size of the shell is matched with the external size of the spherical hinge, and the shell and the spherical hinge are in sliding connection; the first elastic body is arranged above the shell and the spherical hinge and is fixedly connected with the shell; during testing, the two ends of the vertical pipe penetrate through the first channels respectively and are attached to the first elastic body; the adjusting mechanism comprises a plurality of second elastic bodies which are symmetrically arranged, and the two ends of the second elastic bodies are fixedly connected with the hinged support and the frame correspondingly; the method has the beneficial effects that based on the truncation model test concept of the mooring cable, the truncation model test can be carried out on any part of the deepwater standing pipe, so that the model test more truly reflects the flow field and various hydraulic characteristics of the prototype standing pipe.

Description

Technical Field

[0001] The invention belongs to the technical field of deepwater riser detection, and in particular relates to a truncated model test device for bending vibration of a deepwater top-tensioned riser. Background Art

[0002] At present, deepwater offshore oil and gas development has developed to a water depth of more than 3,000 meters. In order to meet the needs of drilling and oil production, deepwater risers must also be able to meet the requirements of such water depths. This undoubtedly poses more challenges to the design and engineering implementation of top-tensioned risers.

[0003] The engineering design of deepwater risers usually requires model tests, but due to the limitations of test conditions, it is still impossible to complete the full-scale model tank test of deepwater risers. At present, the deepest test pool in China and abroad is 10 meters. For a 1,000-meter-long riser, the maximum geometric similarity ratio is 100:1. According to this scale ratio, the diameter of the model can only be 5 mm. According to the similarity theory, the physical indicators of the test medium also need to be transformed accordingly. Since no fluid medium that can meet the similarity relationship has been found, water can only be used for tank tests. As a result, the flow field of a 5 mm diameter cylinder in water will be greatly distorted, and the flow field characteristics around the prototype riser cannot be reproduced.

[0004] At present, the testing of deepwater risers generally adopts non-full-size and non-full-similar model tests, but both cannot truly reflect the hydrodynamic characteristics of the prototype riser during its service life, and unrealistic or even erroneous test results mislead the judgment of designers; in addition, although there are a variety of riser analysis software in the prior art, there are still certain differences between the calculation results of different software and their model test results.

[0005] Hydrodynamic response is an essential design step for deepwater riser design, including design calculation and model test. After completing the hydrodynamic calculation, the designer needs to entrust colleges and universities or research institutions with better test conditions to complete the model test. However, due to the limitations of test conditions, full-scale full-similar model tests cannot be carried out at home and abroad. Only partially similar local model tests can be used to approximate the hydrodynamic response of the prototype, such as similar cross-sectional dimensions but dissimilar lengths and thus dissimilar stiffness, similar Froude numbers but dissimilar Reynolds numbers and thus dissimilar vortex excitation forces, etc.

[0006] In order to solve the existing problems, a truncated model test device for bending vibration of deepwater top-tensioned riser is proposed. Summary of the invention

[0007] The object of the present invention is to provide a truncated model test device for bending vibration of deepwater top-tensioned riser to solve the problems raised in the above-mentioned background technology.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A truncated model test device for bending vibration of deepwater top-tensioned riser comprises:

[0010] A frame, wherein the frame encloses a cavity, and the cavity communicates with the outside;

[0011] Two symmetrically arranged hinge seats, the hinge seats include a first elastic body, a shell, a spherical hinge arranged in the shell and provided with a first channel, the inner dimensions of the shell and the outer dimensions of the spherical hinge match and the two are slidably connected; the first elastic body is arranged above the shell and the spherical hinge, and is fixedly connected to the shell; during the test, both ends of the riser pass through the first channel respectively and fit with the first elastic body;

[0012] Two symmetrically arranged adjusting mechanisms, the adjusting mechanisms include a plurality of symmetrically arranged second elastic bodies, and two ends of the second elastic bodies are respectively fixedly connected to the hinge seat and the frame.

[0013] Preferably, the frame is a hexahedron formed by 12 rods fixedly connected in pairs.

[0014] Preferably, the test device further comprises a rigid pad, which is disposed above the first elastic body and fixedly connected to the first elastic body.

[0015] Preferably, the two adjustment mechanisms and the two hinge seats are respectively located in the space surrounded by the four rods at the top and the space surrounded by the four rods at the bottom.

[0016] Preferably, the second elastic body is a spring, and the spring is symmetrically arranged around the hinge seat.

[0017] Preferably, there are four springs, one end of each spring is fixedly connected to the outer wall of the corresponding hinge seat, and the other end is fixedly connected to the rod body corresponding to the top or bottom of the frame.

[0018] Preferably, the shell includes four parts, and the inner dimensions enclosed by the four parts of the shell match the outer dimensions of the spherical joint.

[0019] Preferably, the first elastic body is a rubber pad.

[0020] The present invention is designed with a frame, which is a hexahedron formed by 12 rods fixedly connected in pairs. The frame surrounds a cavity, which is communicated with the outside and can simulate the flow field of the riser in water.

[0021] The present invention is designed with a hinge seat to provide rotation constraint for the riser and to simulate the cross-sectional rotation stiffness of the riser. The first elastic body provides elastic constraints on both ends of the riser.

[0022] The present invention is designed with a second elastic body, and in particular the second elastic body is a spring, which provides elastic constraints when performing translational displacement in the standpipe end experiment.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention is based on the concept of truncation model test of mooring cables and can carry out truncation model test on any part of deep-water top-tensioned riser, so that the model test can more realistically reflect the flow field and various hydraulic characteristics of the prototype riser. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the present invention;

[0025] Figure 2 A top view of the present invention;

[0026] Figure 3 It is a structural schematic diagram of the hinge seat of the present invention when a riser is installed;

[0027] Figure 4 It is a structural schematic diagram of the hinge seat of the present invention;

[0028] In the figure: 0-vertical pipe; 1-frame; 2-hinge seat; 21-shell; 22-spherical hinge; 221 first channel; 23-first elastic body; 24-pad; 25-bolt; 3-second elastic body. DETAILED DESCRIPTION

[0029] 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.

[0030] See also Figures 1 to 4 , the present invention provides a technical solution:

[0031] Embodiment 1:

[0032] A truncated model test device for bending vibration of deepwater top-tensioned riser comprises:

[0033] The frame 1 forms a cavity which is communicated with the outside. The frame 1 is a hexahedron formed by 12 rods which are fixedly connected in pairs.

[0034] Two hinge seats 2 are symmetrically arranged, and the two hinge seats 2 are respectively located in the space surrounded by the top four rods and the space surrounded by the bottom four rods. The hinge seat 2 includes a first elastic body 23 made of soft material, a shell 21, and a spherical hinge 22 arranged in the shell 21 and provided with a first channel 221. The internal dimensions of the shell 21 match the external dimensions of the spherical hinge 22 and the two are slidably connected; the first elastic body 23 is arranged above the shell 21 and the spherical hinge 22, and is fixedly connected to the shell 21; the shell 21 includes 4 parts, and the internal dimensions surrounded by the 4 parts of the shell 21 match the external dimensions of the spherical hinge 22. During the test, both ends of the vertical pipe 0 pass through the first channel 221 respectively, and fit with the first elastic body 23;

[0035] Two symmetrically arranged adjustment mechanisms, two hinge seats 2 are respectively located in the space surrounded by the top four rods and the space surrounded by the bottom four rods, and the adjustment mechanism includes four second elastic bodies 3 symmetrically arranged around the hinge seats 2, and the second elastic bodies 3 are springs, which are symmetrically arranged around the hinge seats 2. One end of each spring in one adjustment mechanism is fixedly connected to the outer wall of the top hinge seat 2, and the other end is fixedly connected to the rod corresponding to the top of the frame 1; one end of each spring in the other adjustment mechanism is fixedly connected to the outer wall of the bottom hinge seat 2, and the other end is fixedly connected to the rod corresponding to the bottom of the frame 1.

[0036] Embodiment 2:

[0037] A truncated model test device for bending vibration of deepwater top-tensioned riser comprises:

[0038] The frame 1 forms a cavity which is communicated with the outside. The frame 1 is a hexahedron formed by 12 rods which are fixedly connected in pairs.

[0039] Two hinge seats 2 are symmetrically arranged, and the two hinge seats 2 are respectively located in the space surrounded by the top four rods and the space surrounded by the bottom four rods. The hinge seat 2 includes a first elastic body 23 made of rubber, a shell 21, and a spherical hinge 22 arranged in the shell 21 and provided with a first channel 221. The internal dimensions of the shell 21 match the external dimensions of the spherical hinge 22 and the two are slidably connected; the first elastic body 23 is arranged above the shell 21 and the spherical hinge 22, and is fixedly connected to the shell 21; the shell 21 includes 4 parts, and the internal dimensions surrounded by the 4 parts of the shell 21 match the external dimensions of the spherical hinge 22. During the test, both ends of the vertical pipe 0 pass through the first channel 221 respectively, and fit with the first elastic body 23;

[0040] Two symmetrically arranged adjustment mechanisms, two hinge seats 2 are respectively located in the space surrounded by the top four rods and the space surrounded by the bottom four rods, and the adjustment mechanism includes four second elastic bodies 3 symmetrically arranged around the hinge seats 2, and the second elastic bodies 3 are springs, which are symmetrically arranged around the hinge seats 2. One end of each spring in one adjustment mechanism is fixedly connected to the outer wall of the top hinge seat 2, and the other end is fixedly connected to the rod corresponding to the top of the frame 1; one end of each spring in the other adjustment mechanism is fixedly connected to the outer wall of the bottom hinge seat 2, and the other end is fixedly connected to the rod corresponding to the bottom of the frame 1.

[0041] The test device further includes a rigid backing plate 24 . The backing plate 24 is made of metal. The backing plate 24 is disposed above the first elastic body 23 and is fixedly connected to the first elastic body 23 via bolts 25 .

[0042] Embodiment 3:

[0043] A truncated model test device for bending vibration of deepwater top-tensioned riser comprises:

[0044] The frame 1 forms a cavity which is communicated with the outside. The frame 1 is a hexahedron formed by 12 rods which are fixedly connected in pairs.

[0045] Two hinge seats 2 are symmetrically arranged, and the two hinge seats 2 are respectively located in the space surrounded by the top four rods and the space surrounded by the bottom four rods. The hinge seat 2 includes a first elastic body 23 made of rubber, a shell 21, and a spherical hinge 22 arranged in the shell 21 and provided with a first channel 221. The internal dimensions of the shell 21 match the external dimensions of the spherical hinge 22 and the two are slidably connected; the first elastic body 23 is arranged above the shell 21 and the spherical hinge 22, and is fixedly connected to the shell 21; the shell 21 includes 4 parts, and the internal dimensions surrounded by the 4 parts of the shell 21 match the external dimensions of the spherical hinge 22. During the test, both ends of the vertical pipe 0 pass through the first channel 221 respectively, and fit with the first elastic body 23;

[0046] Two symmetrically arranged adjustment mechanisms, two hinge seats 2 are respectively located in the space surrounded by the top four rods and the space surrounded by the bottom four rods, and the adjustment mechanism includes two second elastic bodies 3 symmetrically arranged around the hinge seats 2, and the second elastic bodies 3 are springs. One end of each spring in one adjustment mechanism is fixedly connected to the outer wall of the top hinge seat 2, and the other end is fixedly connected to the rod corresponding to the top of the frame 1; one end of each spring in the other adjustment mechanism is fixedly connected to the outer wall of the bottom hinge seat 2, and the other end is fixedly connected to the rod corresponding to the bottom of the frame 1.

[0047] The test device further includes a rigid pad 24 , which is made of a steel plate. The pad 24 is disposed above the first elastic body 23 and is fixedly connected to the first elastic body 23 via bolts 25 .

[0048] The working principle and use process of the present invention:

[0049] The present invention is placed in a water tank, in which there is a flow meter. The designer takes a part of the riser 0, on which strain gauges and sensors are installed, and inserts the two ends of the riser 0 into the first channels 221 of the two spherical hinges 22 respectively. During the test, the riser is in the water flow field, and the hinge seat 2 provides rotation constraints for the riser 0, wherein the first elastic body 23 provides elastic constraints for the two ends of the riser 0, and the second elastic body 3 provides elastic constraints for the end of the riser 0 during translational displacement. In the experiment, the strain gauge and sensor collect the strain and acceleration data of the riser 0, and the flow meter records the water flow data. Finally, the bending vibration of the riser 0 is analyzed based on the strain, acceleration and water flow data of the riser 0.

[0050] Although embodiments of the present invention have been shown and described (see the above detailed description for details), it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

[0051] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, 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 limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0052] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

Claims

1. A truncated model test device for bending vibration of deepwater top-tensioned riser, characterized in that: The test device comprises: A frame (1), wherein the frame (1) encloses a cavity, and the cavity communicates with the outside; Two symmetrically arranged hinge seats (2), the hinge seats (2) comprising a first elastic body (23), a shell (21), and a spherical hinge (22) disposed in the shell (21) and provided with a first channel (221), the inner dimensions of the shell (21) and the outer dimensions of the spherical hinge (22) matching each other and the two being slidably connected; the first elastic body (23) being disposed above the shell (21) and the spherical hinge (22) and being fixedly connected to the shell (21); during the test, the two ends of the riser (0) respectively pass through the first channel (221) and fit the first elastic body (23); Two symmetrically arranged adjustment mechanisms, the adjustment mechanisms comprising a plurality of symmetrically arranged second elastic bodies (3), the two ends of the second elastic bodies (3) being respectively fixedly connected to the hinge seat (2) and the frame (1).

2. A truncation model test device for bending vibration of deepwater top-tensioned riser according to claim 1, characterized in that: The frame (1) is a hexahedron formed by 12 rods fixedly connected in pairs.

3. A truncation model test device for deepwater top-tensioned riser bending vibration according to claim 1, characterized in that: The test device also includes a rigid pad (24), which is disposed above the first elastic body (23) and is fixedly connected to the first elastic body (23).

4. A truncation model test device for deepwater top-tensioned riser bending vibration according to claim 2, characterized in that: The two adjustment mechanisms and the two hinge seats (2) are respectively located in a space surrounded by the four rod bodies at the top and a space surrounded by the four rod bodies at the bottom.

5. A truncation model test device for deepwater top-tensioned riser bending vibration according to any one of claims 1 to 4, characterized in that: The second elastic body (3) is a spring, and the spring is symmetrically arranged around the hinge seat (2).

6. A truncation model test device for bending vibration of deepwater top-tensioned riser according to claim 5, characterized in that: There are four springs, one end of each spring is fixedly connected to the outer wall of the corresponding hinge seat (2), and the other end is fixedly connected to the rod body corresponding to the top or bottom of the frame (1).

7. A truncation model test device for deepwater top-tensioned riser bending vibration according to claim 1, characterized in that: The shell (21) comprises four parts, and the internal dimensions enclosed by the four parts of the shell (21) match the external dimensions of the spherical joint (22).

8. The truncated model test device for bending vibration of deepwater top-tensioned riser according to claim 1, characterized in that: The first elastic body (23) is a rubber pad.

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