Device and method for testing efficiency of vortex-induced vibration suppressor of flexible pipe cable

Abstract

The invention discloses a flexible pipe cable vortex-induced vibration suppressor efficiency test device and method. The device comprises a circulating water tank, a two-degree-of-freedom elastic motion device, a vortex-induced vibration response measurement system, a PIV three-dimensional visualization system, a vortex-induced vibration suppressor and a data post-processing platform. The two-degree-of-freedom elastic movement device is arranged at the top of the circulating water tank A clamping mechanism is arranged on the two-degree-of-freedom elastic movement device; the PIV three-dimensional visualization system comprises a laser irradiation system and three high-speed cameras; the three high-speed cameras are arranged according to a non-coplanar triangular layout; the three high-speed cameras are focused on a wake flow area of the pipe cable model; the vortex-induced vibration suppressor is detachably installed on the pipe cable model. By adjusting the vibration freedom degree, dynamically adjusting the spring rigidity and synchronously collecting three-dimensional flow field data, the action mechanism of the suppressor can be accurately deconstructed, and therefore reliable data support is provided for assessment of the suppression effect of the suppressor, exploration of the suppression principle and calibration of a simulation model.

Description

Technical Field

[0001] The present invention relates to the technical field of ocean engineering test equipment, and more specifically, to an effectiveness test device and method for a flexible pipe and cable vortex-induced vibration suppressor. Background Art

[0002] In the development of deep-sea oil and gas resources, flexible pipes and cables are widely used in key links such as oil and gas transportation, chemical agent injection, and subsea control signal transmission. However, affected by ocean currents, flexible pipes and cables with a large length-to-diameter ratio are prone to complex vortex-induced vibrations, showing multi-directional coupled vibration modes and generating non-linear interference between different directions. Such vibrations can not only cause structural fatigue and shorten the service life, but also pose a serious threat to the stability and safety of the system. Therefore, the development of effective vortex-induced vibration suppression devices has become a key measure to ensure the reliable operation of the system. However, existing research shows that there is a strong coupling between flexible structures and the surrounding flow field, and it is difficult to comprehensively capture their true dynamic responses only relying on theoretical modeling. To accurately evaluate the suppression effect of the pipe and cable vortex-induced vibration suppressor and improve the credibility of the numerical model, it is of great significance to use experimental means for verification and performance testing.

[0003] Chinese patent document CN102331332A discloses a cylinder vortex-induced vibration test device with controllable vibration degrees of freedom, but this test method ignores the interference of the test device itself on the hydrodynamic environment around the cylinder when it is immersed in the flow field. The presence of the test device in the flow field will cause abnormal turbulence and local pressure changes, resulting in the test results of vortex-induced vibration deviating from the actual working conditions and weakening the reference value of the test data for actual engineering applications. Although Chinese patent documents CN112213064A and CN111089697A adopt partial non-invasive designs (placing the support frame outside the water tank), their tie rods are still immersed in the flow field and still cause obvious disturbances to the flow field under high-speed flow conditions. In addition, the existing vortex-induced vibration test devices cannot capture the three-dimensional flow field structure in the downstream area of the pipe and cable, and it is difficult to accurately reveal the interaction relationship between the vortex-induced vibration displacement and the wake turbulence characteristics, so the action mechanism of the vortex-induced vibration suppressor cannot be effectively evaluated.

[0004] Therefore, it is necessary to design a non-invasive vortex-induced vibration experiment device that can realize the coordinated measurement of multiple parameters such as flow field velocity to accurately deconstruct the action mechanism of the suppressor, evaluate the suppression effect, and provide reliable data. Summary of the Invention

[0005] In view of this, the present invention provides an effectiveness test device and method for a flexible pipe and cable vortex-induced vibration suppressor, and the purpose is to solve the problems existing in the prior art.

[0006] To solve the above technical problems, the present invention adopts the following technical solutions: A test device for the effectiveness of a flexible pipe and cable vortex-induced vibration suppressor, comprising: A circulating water tank; A two-degree-of-freedom elastic motion device; the two-degree-of-freedom elastic motion device is arranged on the top of the circulating water tank; a clamping mechanism for fixedly installing a pipe and cable model is arranged on the two-degree-of-freedom elastic motion device, which is used to support the clamping mechanism and avoid the generation of wake vortices or pressure disturbances by the clamping mechanism itself; A vortex-induced vibration response measurement system; the vortex-induced vibration response measurement system is used to measure the vibration displacement time history and fluid load of the pipe and cable model; A PIV three-dimensional visualization system; the PIV three-dimensional visualization system includes a laser irradiation system and three high-speed cameras; the three high-speed cameras are arranged in a non-coplanar triangular layout, wherein two of the high-speed cameras are symmetrically arranged on the left and right sides of the circulating water tank, and one high-speed camera is arranged above the circulating water tank; the three high-speed cameras are focused on the wake region of the pipe and cable model; A vortex-induced vibration suppressor; the vortex-induced vibration suppressor is detachably installed on the pipe and cable model; A data post-processing platform; the data post-processing platform is used for data collection and processing.

[0007] Preferably, water inlets and outlets are respectively arranged on the front and rear sides of the circulating water tank; a variable-frequency water pump is arranged on the water inlet.

[0008] Preferably, a flow guide plate is arranged in the circulating water tank; the flow guide plate is located on the front side of the two-degree-of-freedom elastic motion device.

[0009] Preferably, the two-degree-of-freedom elastic motion device includes a transverse guide rail and two longitudinal guide rails; the two longitudinal guide rails are symmetrically arranged on the left and right sides at the top of the circulating water tank; a longitudinal slider is slidably connected to the longitudinal guide rail; the front and rear ends of the longitudinal slider are respectively connected to the front and rear ends of the longitudinal guide rail through longitudinal springs; a transverse slider is slidably connected to the transverse guide rail; the left and right ends of the transverse slider are respectively connected to the two ends of the transverse guide rail through transverse springs.

[0010] Preferably, the clamping mechanism includes two clamping arms; the two clamping arms are symmetrically arranged on both sides of the transverse slider; an arc-shaped clamping plate is arranged at the lower end of each clamping arm; the two arc-shaped clamping plates are arranged oppositely for clamping and fixing the pipe and cable model.

[0011] Preferably, corresponding first positioning pin holes are provided on the longitudinal guide rail and the longitudinal slider; corresponding second positioning pin holes are provided on the transverse guide rail and the transverse slider.

[0012] Preferably, the vortex-induced vibration response measurement system includes an acceleration sensor and a force sensor; the acceleration sensors are provided on both the in-line slider and the cross-flow slider; the force sensor is disposed on the pipeline model.

[0013] Preferably, the laser irradiation system includes tracer particles, a laser emitter, and a light sheet mirror; the laser emitter is disposed below the circulating water tank; the laser emitter expands the laser beam into a plane through the light sheet mirror to visualize the tracer particles.

[0014] A method for testing the effectiveness of a flexible pipeline vortex-induced vibration suppressor, using the above-mentioned flexible pipeline vortex-induced vibration suppressor effectiveness test device, includes the following steps: Step 1: Install a two-degree-of-freedom elastic motion device and a clamping mechanism to complete the construction of the test system in the circulating water tank. Replace the corresponding arc-shaped clamping plates according to the size of the pipeline model and adjust the spatial positions of each guide rail to ensure that the pipeline model is located in the core area of the observed flow field. Among them, a force sensor is pre-installed on the pipeline model; Step 2: Determine the main parameters of the pipeline model according to the dynamic similarity criterion. At the same time, calculate the bottom boundary layer thickness of the circulating water tank and adjust the geometric position of the pipeline model in the flow field space to ensure that the bottom end of the pipeline model is outside the boundary layer; Step 3: Install acceleration sensors on each slider of the two-degree-of-freedom elastic motion device, arrange the high-speed cameras of the PIV three-dimensional visualization system and the laser irradiation system, determine the laser light sheet area, and adjust the angles and focal lengths of the high-speed cameras to ensure the acquisition accuracy of the flow field data; Step 4: Start the variable-frequency water pump to control the fluid flow rate. After the vibration of the pipeline model reaches stability, trigger the multi-channel data synchronous acquisition, and collect the vibration displacement time history, fluid load, and three-dimensional flow velocity of the flow field of the pipeline model without installing the suppressor; Step 5: Install a vortex-induced vibration suppressor at the preset position of the pipeline model. Conduct a sensitivity analysis of the installation parameters according to the type of the tested vortex-induced vibration suppressor, collect the vibration displacement time history, fluid load, and three-dimensional flow velocity of the flow field of the pipeline model, determine the optimal parameters of the vortex-induced vibration suppressor, and at the same time use the test data to verify the simulation model; Step 6: Adjust the flow rate, spring stiffness, and motion degree-of-freedom parameters according to the test requirements, repeat Step 5, and draw the corresponding parameter curves and flow field characteristics through the combination of different parameters to provide data support for the evaluation of the effectiveness of the vortex-induced vibration suppressor, the verification of relevant numerical models, and the analysis of the working principle of the suppressor.

[0015] The present invention has achieved the following technical effects compared with the prior art: 1) The present invention provides a two-degree-of-freedom elastic motion device, which solves the problem of motion degree-of-freedom constraint in traditional devices, can accurately reproduce the ocean current field environment and realize multi-dimensional dynamic simulation of the vortex-induced vibration of the pipeline and cable, and solves the problem of interference of the traditional clamping device on the flow field through a non-invasive structure design.

[0016] 2) Through the ball guide rail, the present invention can reduce the sliding friction and achieve the lossless transmission of the tiny vibration of the pipeline and cable.

[0017] 3) By coordinating the vortex-induced vibration response measurement system and the PIV three-dimensional visualization system, the present invention can collect parameters such as vibration displacement, fluid load and three-dimensional flow field characteristics.

[0018] 4) The present invention determines the size parameters of the pipeline and cable scale model according to the dynamic similarity criterion, simulates the real stiffness of the test pipeline and cable through the spring equivalent stiffness model, and calculates the bottom boundary layer thickness of the circulating water tank at the same time to avoid its influence on the test; the acceleration signal is converted into a vibration signal by the spectrum conversion method, and the comprehensive evaluation of the suppressor suppression effect, the effective verification of the simulation numerical model and the in-depth exploration of the suppressor working principle are realized through data results such as the response of mode and amplitude, frequency response and vibration trajectory analysis.

[0019] 5) By adjusting the vibration degree of freedom, dynamically adjusting the spring stiffness and synchronously collecting three-dimensional flow field data, the present invention can accurately deconstruct the action mechanism of the suppressor, so as to provide reliable data support for the evaluation of the suppressor suppression effect, the exploration of the suppression principle and the calibration of the simulation model. Brief Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of an efficiency test device for a flexible pipeline and cable vortex-induced vibration suppressor of the present invention; Figure 2 is a schematic structural diagram of a two-degree-of-freedom elastic motion device; Figure 3 is a schematic structural diagram of a clamping mechanism; In the figure: 1. Circulating water tank; 2. Two-degree-of-freedom elastic motion device; 201. Transverse guide rail; 202. Along-flow guide rail; 203. Along-flow slider; 204. Along-flow spring; 205. Transverse slider; 206. Transverse spring; 3. Clamping mechanism; 301. Clamping arm; 302. Arc-shaped clamping plate; 4. High-speed camera; 5. Pipeline and cable model; 6. Variable-frequency water pump; 7. Flow deflector; 8. Acceleration sensor; 9. Force sensor; 10. Laser emitter; 11. Data post-processing platform. Detailed Embodiment

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] Referring to Figures 1-3 As shown, the present invention discloses an effectiveness test device for suppressing vortex-induced vibration of flexible pipe cables, including: a circulating water tank 1, a two-degree-of-freedom elastic motion device 2, a vortex-induced vibration response measurement system, a PIV three-dimensional visualization system, a vortex-induced vibration suppressor, and a data post-processing platform 11; the two-degree-of-freedom elastic motion device 2 is arranged on the top of the circulating water tank 1; a clamping mechanism 3 is provided on the two-degree-of-freedom elastic motion device 2; the pipe cable model 5 is vertically arranged in the core area of the flow field, and the upper end of the pipe cable model 5 is clamped and fixed by the clamping mechanism 3; the vortex-induced vibration response measurement system is used to measure the vibration displacement time history and fluid load of the pipe cable model 5; the PIV three-dimensional visualization system includes a laser irradiation system and three high-speed cameras 4; the three high-speed cameras 4 are arranged in a non-coplanar triangular layout, wherein, two high-speed cameras 4 are symmetrically arranged on the left and right sides of the circulating water tank 1, and one high-speed camera 4 is arranged above the circulating water tank 1; the three high-speed cameras 4 focus on the wake area of the pipe cable model 5; the vortex-induced vibration suppressor is detachably installed on the pipe cable model 5; the data post-processing platform 11 is used for data collection and processing.

[0023] The above technical solution reduces the interference to the flow field through the non-invasive design of arranging the two-degree-of-freedom elastic motion device on the top of the circulating water tank, avoids the generation of wake vortices or pressure disturbances by the clamping mechanism itself, and improves the accuracy of the test results.

[0024] In this embodiment, an inlet and an outlet are respectively provided on the front and rear sides of the circulating water tank 1; a variable-frequency water pump 6 is provided on the inlet.

[0025] In this embodiment, a flow guide plate 7 is provided in the circulating water tank 1; the flow guide plate 7 is provided with flow guide holes; the flow guide plate 7 is located on the front side of the two-degree-of-freedom elastic motion device 2; during use, through the coordinated action of the variable-frequency water pump 6 and the flow guide plate 7, the fluid flows uniformly in the test section of the circulating water tank.

[0026] In this embodiment, the two-degree-of-freedom elastic motion device 2 includes a transverse guide rail 201 and two longitudinal guide rails 202; the two longitudinal guide rails 202 are symmetrically arranged on the left and right sides at the top of the circulation water tank 1; a longitudinal slider 203 is slidably connected to the longitudinal guide rail 202; the longitudinal guide rail 202 is arranged parallel to the fluid flow direction in the circulation water tank 1, so that the longitudinal slider 203 can horizontally slide along the fluid flow direction on the longitudinal guide rail 202; the front and rear ends of the longitudinal slider 203 are respectively connected to the front and rear ends of the longitudinal guide rail 202 through longitudinal springs 204, which facilitates the automatic reset of the longitudinal slider 203; the transverse guide rail 201 is perpendicular to the longitudinal guide rail 202; both ends of the transverse guide rail 201 are respectively fixedly connected to the two longitudinal sliders 203; a transverse slider 205 is slidably connected to the transverse guide rail 201; the left and right ends of the transverse slider 205 are respectively connected to both ends of the transverse guide rail 201 through transverse springs 206, which facilitates the automatic reset of the transverse slider 205.

[0027] In this embodiment, the longitudinal springs 204 and the transverse springs 206 can both be replaced, and the stiffness parameters are dynamically adjusted according to the test requirements.

[0028] In this embodiment, both the transverse guide rail 201 and the longitudinal guide rail 202 adopt ball guide rails to reduce the track friction and ensure the lossless transmission of vibration.

[0029] In this embodiment, the clamping mechanism 3 includes two clamping arms 301; the two clamping arms 301 are symmetrically arranged on both sides of the transverse slider 205; an arc-shaped clamping plate 302 is provided at the lower end of each clamping arm 301; the two arc-shaped clamping plates 302 are arranged oppositely for clamping and fixing the cable model 5, and during use, different arc-shaped clamping plates can be replaced as needed to adapt to cable models of different specifications.

[0030] In this embodiment, corresponding first positioning pin holes are provided on the longitudinal guide rail 202 and the longitudinal slider 203; corresponding second positioning pin holes are provided on the transverse guide rail 201 and the transverse slider 205; during use, by inserting a positioning pin into the first positioning pin hole or the second positioning pin hole, the longitudinal slider 203 or the transverse slider 205 can be fixed, thereby realizing a single-degree-of-freedom vortex-induced vibration test; by releasing the longitudinal slider 203 and the transverse slider 205 simultaneously, a two-degree-of-freedom coupled motion test can be realized.

[0031] In this embodiment, the vortex-induced vibration response measurement system includes an acceleration sensor 8 and a force sensor 9; acceleration sensors 8 are provided on both the longitudinal slider 203 and the transverse slider 205 for, in real time, capturing the motion data of the cable model; the force sensor 9 is arranged on the outer side surface of the cable model 5 for measuring the fluid force received by the cable model.

[0032] In this embodiment, the laser irradiation system includes tracer particles, a laser emitter 10, and a light sheet mirror; the laser emitter 10 is disposed below the circulation water tank 1; the tracer particles are scattered in the fluid; the laser emitter 10 expands the laser beam into a plane through the light sheet mirror to visualize the tracer particles.

[0033] In this embodiment, the vortex-induced vibration suppressor is detachably mounted on the pipe cable model 5 through a pipeline clamp.

[0034] In this embodiment, the data post-processing platform 11 uses a high-computing power computer to perform original image processing, extract the displacement vector field of the tracer particles, and analyze the flow field characteristics.

[0035] A method for testing the effectiveness of a flexible pipe cable vortex-induced vibration suppressor, using the above-mentioned flexible pipe cable vortex-induced vibration suppressor effectiveness test device, includes the following steps: Step 1: First, fix the downstream guide rail 202 at a preset position at the top of the test section of the circulation water tank. Subsequently, fix both ends of the lateral guide rail 201 on two downstream sliders 203 respectively. Then, connect both ends of the downstream sliders 203 to both ends of the downstream guide rail 202 through downstream springs 204, and connect both ends of the lateral sliders 205 to both ends of the lateral guide rail 201 through lateral springs 206. Then, replace the corresponding arc-shaped clamping plates 302 according to the diameter of the pipe cable model. Finally, calibrate the installation positions of each guide rail and slider so that the pipe cable model 5 is located in the core area of the flow field to complete the construction of the test system; Step 2: Based on the dynamic similarity criterion, deduce and calculate the test phenomenon through dimensionless parameter matching to determine the size parameters of the pipe cable scale model; Calculate the Reynolds number of the pipe cable prototype according to the Reynolds number calculation formula:

[0036] In the formula, is the Reynolds number of the pipe cable prototype, is the diameter of the pipe cable prototype, and thus determine the scale ratio ( is the diameter of the pipe model), so that the model Reynolds number is as close as possible to ; After ensuring that the above standards are within a certain acceptable range, determine the final pipe cable model parameters and ; To avoid the interference of the bottom boundary layer of the circulation water tank 1 on the flow field around the pipe cable model, it is necessary to determine the bottom installation height of the pipe cable model 5: For the boundary layer formed at the bottom 1 of the circulation water tank, it can be regarded as a flat plate laminar boundary layer. Calculate the thickness according to the Blasius laminar boundary layer theory and set the installation height:

[0037]

[0038] In the formula, is the distance along the flow direction at the bottom of the water inlet duct cable model, is the installation height.

[0039] Step 3: Arrange acceleration sensors 8 on the slider 203 in the flow direction and the cross slider 205, and ensure that the acceleration sensors 8 are rigidly connected to the corresponding sliders through magnetic clamping fixtures and the axes are aligned with the vibration direction of the pipe cable model 5; use a high-resolution data acquisition system to synchronously collect the acceleration time-domain signals, and continuously record for a time ≥ 300 vortex shedding periods to cover the low-frequency components; The steps of converting the acceleration signal into a displacement signal by using the spectrum conversion method are as follows: The discrete acceleration signal obtained by data acquisition is subjected to FFT to obtain its spectrum ;

[0040] The vibration displacement signal is:

[0041] where the acceleration harmonic component is calculated by and the displacement harmonic component is calculated by ; A force sensor 9 is embedded on the pipe cable model 5 and installed by flange bolt pre-tightening to synchronously measure the drag force in the flow direction and the lift force in the cross direction acting on the pipe cable model 5 by the fluid.

[0042] To accurately reconstruct the three-dimensional flow field structure, three high-resolution high-speed cameras 4 are arranged in a non-coplanar triangular layout; among them, one high-speed camera is directly facing the measurement area, and the other two high-speed cameras are symmetrically distributed at an inclination angle of ±30°, and a 1-mm thick sheet of light is generated in combination with a laser emitter 10 (wavelength 532 nm, single-pulse energy 200 mJ); the tracer particles are 50-μm hollow glass microspheres with a concentration of 8-12 particles / mm³ and are uniformly dispersed through a flow stabilizer; The method for constructing the three-dimensional flow field: Perform multi-view joint calibration through a three-dimensional calibration target (checkerboard grid spacing 2 mm, Z-direction layer spacing 5 mm), correct the lens distortion and fuse the fields of view of the three cameras; synchronously identify the projection coordinates of the particles in the three cameras, use the triangulation method to calculate the three-dimensional spatial positions, and analyze the continuous-frame particle displacements in combination with a 64×64×64 voxel cross-correlation window to output the instantaneous three-dimensional velocity field; Step 4: Existing research shows that flexible pipe cables have a large length-to-diameter ratio, so the pipe cables in the marine environment can be assumed to be beam models. In the vortex-induced vibration test, since the length of the pipe cable model used is short and the overall stiffness is large, it can be approximately regarded as a rigid body. Therefore, a simplified model of a cantilever beam with a spring at one end can be used for equivalent treatment of the flexible pipe cable. To ensure that the equivalent bending stiffness of the pipe cable model is consistent with that of the prototype pipeline, based on the actual bending stiffness of the flexible pipe cable, a conversion relationship of the spring elastic coefficient is established through the equivalent model of the cantilever beam. The specific formula is:

[0043] In the formula, is the elastic modulus of the pipe cable, is the moment of inertia of the cross-section, is the length of the pipe cable, realizing the equivalent matching of the prototype stiffness and the test spring.

[0044] Step 5: Conduct sensitivity tests on installation parameters. Install a vortex-induced vibration suppressor at the preset position of the pipe cable model 5. According to the structural characteristics of the suppressor, by constructing a multivariable test matrix system, obtain the optimal setting parameters of the suppressor to maximize the vibration suppression efficiency. Taking the spiral plate suppressor as an example, it can be adjusted by adjusting the coverage rate of the spiral plate and the angle between the axis of the spiral edge strip suppressor and the oncoming flow; For the flow field regulation characteristics of the spiral plate suppressor, select the coverage rate of the spiral edge strip suppressor and the angle between the axis and the oncoming flow for orthogonal grouping tests to quickly obtain the optimal installation parameters; Record the best parameters of the vortex-induced vibration suppressor, and synchronously collect the vibration displacement time history, fluid load, and three-dimensional flow velocity of the flow field of the pipe cable model to facilitate the subsequent evaluation of the suppressor performance; Step 6: Adjust the flow velocity, spring stiffness, and degree-of-freedom parameters, record the vibration displacement time history, fluid load, and three-dimensional flow velocity of the flow field under the acquisition combination, and complete different test purposes; 1) Vibration suppressor performance test and analysis of suppression principle Before conducting the vortex-induced vibration test of the flexible pipe cable, it is first necessary to calculate the natural frequency of the riser model. Research shows that when lock-in occurs, , where is the self-vibration frequency of the pipe cable model, is the vortex-induced vibration frequency, is the natural frequency of the pipe cable model. Therefore, through the flow velocity when different modes are excited to the lock-in state can be estimated, providing a basis for test design; Taking the pipe cable model of homogeneous material as an example, the formula for calculating the natural frequency of the model is:

[0045] In the formula is the modal number, is the elastic modulus of the model, is the moment of inertia of the model cross-section, is the equivalent mass of the model, is the model length; Set a fixed flow velocity in the circulating water channel, keep the spring stiffness connecting the slider fixed, and simulate the structural constraints under actual working conditions. During the test, the two-degree-of-freedom motions are both measured, the vibration displacement time history of the pipeline and cable model is collected in real time, and the displacements of the two degrees of freedom, the lift coefficient of the pipeline and cable model and the drag coefficient are measured and recorded for their variation time histories, and the variation curves are respectively plotted; Compare the data recorded in the benchmark test in the state without the suppressor in Step Four with the data collected in the state with the suppressor installed in Step Five, and evaluate the effectiveness of the suppressor in combination with the pipeline and cable damping rate, the change rate of the drag coefficient, and the change rate of the lift coefficient:

[0046]

[0047]

[0048] Combined with the visualized flow field obtained by PIV, by analyzing the influence of the suppressor on the vortex shedding form and the damage of the suppressor to the structure of the pipeline and cable wake flow field, the working principle of the suppressor can be further analyzed, which is convenient for the optimization and improvement of the suppressor in subsequent engineering research.

[0049] 2) Sensitivity test of suppressor parameters and verification of simulation model Set the flow velocity range U = 0.5~2.0 m / s (step size ΔU = 0.3 m / s) in the circulating water channel, keep the spring stiffness connecting the slider fixed, and arrange it according to the above Steps One, Two, Three, and Four. The test is divided into a benchmark model without a suppressor and a model with a suppressor installed. The vibration displacement time history and fluid load are collected at stepwise flow velocities in sequence, and the three-dimensional flow velocities of the flow field are captured by a high-speed camera; Through the sensitivity analysis of suppressor parameters and multi-condition (flow velocity, pipeline stiffness) tests, the fluid-structure interaction simulation models of software such as ANSYS can be calibrated in multiple dimensions by using the obtained vibration displacement and three-dimensional flow data (flow velocity, vorticity, etc.) of the flow field. This multi-dimensional calibration method can effectively optimize the vortex-induced vibration simulation model, significantly improve the accuracy of the model, and enhance the engineering prediction accuracy.

[0050] In this embodiment, the acceleration sensor 8 is a piezoelectric acceleration sensor; the force sensor 9 uses a micro six-dimensional force sensor.

[0051] It should be noted that the definitions of the coordinate system in the present invention are as follows: along the flow direction - the horizontal water flow direction, perpendicular to the axis of the pipeline and cable model; transverse direction - perpendicular to the water flow direction in the horizontal plane; vertical direction - along the axis direction of the pipeline and cable model.

[0052] The above are only preferred embodiments of the present invention, and do not impose any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A test device for the effectiveness of a flexible pipe and cable vortex-induced vibration suppressor, characterized in that, Including: Circulating water tank (1); Two-degree-of-freedom elastic motion device (2); The two-degree-of-freedom elastic motion device (2) is arranged on the top of the circulating water tank (1); A clamping mechanism (3) for fixedly installing the pipeline cable model (5) is provided on the two-degree-of-freedom elastic motion device (2); Vortex-induced vibration response measurement system; The vortex-induced vibration response measurement system is used to measure the vibration displacement time history and fluid load of the pipeline cable model (5); PIV three-dimensional visualization system; The PIV three-dimensional visualization system includes a laser irradiation system and three high-speed cameras (4); The three high-speed cameras (4) are arranged in a non-coplanar triangular layout. Among them, two of the high-speed cameras (4) are symmetrically arranged on the left and right sides of the circulating water tank (1), and one high-speed camera (4) is arranged above the circulating water tank (1); The three high-speed cameras (4) are focused on the wake region of the pipeline cable model (5); Vortex-induced vibration suppressor; The vortex-induced vibration suppressor is detachably installed on the pipeline cable model (5); Data post-processing platform (11); The data post-processing platform (11) is used for data collection and processing.

2. The effectiveness test device for suppressing vortex-induced vibration of a flexible pipe cable according to claim 1, wherein, Water inlets and outlets are respectively arranged on the front and rear sides of the circulating water tank (1); A variable-frequency water pump (6) is provided on the water inlet.

3. The effectiveness test device for suppressing vortex-induced vibration of a flexible pipe and cable according to claim 2, wherein A flow guide plate (7) is arranged in the circulating water tank (1); The flow guide plate (7) is located on the front side of the two-degree-of-freedom elastic motion device (2).

4. The effectiveness test device for suppressing vortex-induced vibration of a flexible pipe and cable according to claim 1, wherein The two-degree-of-freedom elastic motion device (2) includes a transverse guide rail (201) and two longitudinal guide rails (202); The two longitudinal guide rails (202) are symmetrically arranged on the left and right sides at the top of the circulating water tank (1); A longitudinal slider (203) is slidably connected to the longitudinal guide rail (202); The front and rear ends of the longitudinal slider (203) are respectively connected to the front and rear ends of the longitudinal guide rail (202) through longitudinal springs (204); Both ends of the transverse guide rail (201) are fixedly connected to the two longitudinal sliders (203); A transverse slider (205) is slidably connected to the transverse guide rail (201); The left and right ends of the transverse slider (205) are respectively connected to both ends of the transverse guide rail (201) through transverse springs (206).

5. The effectiveness test device for suppressing vortex-induced vibration of a flexible pipe cable according to claim 4, wherein The clamping mechanism (3) includes two clamping arms (301); The two clamping arms (301) are symmetrically arranged on both sides of the transverse slider (205); An arc-shaped clamping plate (302) is provided at the lower end of each clamping arm (301); The two arc-shaped clamping plates (302) are arranged oppositely for clamping and fixing the pipeline cable model (5).

6. The effectiveness test device for suppressing the vortex-induced vibration of a flexible pipe and cable according to claim 5, wherein, Corresponding first positioning pin holes are provided on the longitudinal guide rail (202) and the longitudinal slider (203); Corresponding second positioning pin holes are provided on the transverse guide rail (201) and the transverse slider (205).

7. The effectiveness test device for suppressing vortex-induced vibration of a flexible pipe cable according to claim 5, characterized in that, The vortex-induced vibration response measurement system includes an acceleration sensor (8) and a force sensor (9); the acceleration sensor (8) is provided on both the along-flow slider (203) and the cross-flow slider (205); the force sensor (9) is disposed on the pipeline model (5).

8. The effectiveness test device for suppressing vortex-induced vibration of a flexible pipe cable according to claim 1, wherein The laser irradiation system includes tracer particles, a laser emitter (10) and a light sheet mirror; the laser emitter (10) is disposed below the circulating water tank (1); the laser emitter (10) expands the laser beam into a plane through the light sheet mirror to realize the visualization of the tracer particles.

9. A method for testing the effectiveness of a flexible pipe and cable vortex-induced vibration suppressor, characterized in that, Using the flexible pipeline vortex-induced vibration suppressor performance test device as described in any one of claims 1-8, comprising the following steps: Step 1: Install the two-degree-of-freedom elastic motion device (2) and the clamping mechanism (3) to complete the construction of the test system in the circulating water tank (1), and ensure that the pipeline model (5) is located in the core area of the observed flow field; Step 2: Determine the main parameters of the pipeline model (5) according to the dynamic similarity criterion, and at the same time calculate the bottom boundary layer thickness of the circulating water tank (1), and adjust the geometric position of the pipeline model (5) in the flow field space to ensure that the bottom end of the pipeline model (5) is outside the boundary layer; Step 3: Install the vortex-induced vibration response measurement system, arrange the high-speed camera (4) of the PIV three-dimensional visualization system and the laser irradiation system, determine the laser light sheet area, and adjust the angle and focal length of the high-speed camera (4) to ensure the acquisition accuracy of the flow field data; Step 4: Start the circulating water tank (1) and load the target flow velocity. After the vibration of the pipeline model (5) reaches stability, trigger the multi-channel data synchronous acquisition, and collect the vibration displacement time history, fluid load and three-dimensional flow velocity of the flow field of the pipeline model (5) without installing the suppressor; Step 5: Install the vortex-induced vibration suppressor at the preset position of the pipeline model (5), conduct a sensitivity analysis of the installation parameters according to the type of the tested vortex-induced vibration suppressor, collect the vibration displacement time history, fluid load and three-dimensional flow velocity of the flow field of the pipeline model (5), determine the optimal parameters of the vortex-induced vibration suppressor, and at the same time use the test data for the verification of the simulation model; Step 6: Adjust the flow velocity, spring stiffness and motion degree-of-freedom parameters according to the test requirements, repeat Step 5, draw the corresponding parameter curves and flow field characteristics through the combination of different parameters, and provide data support for the evaluation of the performance of the vortex-induced vibration suppressor, the verification of relevant numerical models and the analysis of the working principle of the suppressor.

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