Mooring Model Stiffness Calibration Device and Calibration Measurement Method

Abstract

The present invention belongs to the field of hydrodynamic tests for ocean engineering, and discloses a mooring model stiffness calibration device and a calibration measurement method. The calibration device includes a fixed frame, on which a frame guide rail is installed. A sliding frame is installed on the frame guide rail, and a sliding table guide rail is installed on the sliding frame. A slider is installed on the sliding table guide rail. The slider is fixedly connected to the sliding table and can move along the sliding table guide rail together. A laser displacement ranging sensor is installed on one side of the sliding table, and a laser baffle is installed at one end of the sliding frame. A first tension sensor and a measuring turntable are also installed on the sliding table. A sheave mechanism corresponding to the measuring turntable is also installed on the fixed frame. A second tension sensor and an inclination sensor are installed on the measuring turntable. The laser displacement ranging sensor, the first and second tension sensors, and the inclination sensor are all connected to a data collector through data lines, and the data collector is connected to a data processing and control system. It can achieve continuous, two-way, automatic, and precise measurement.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrodynamic tests for ocean engineering, and particularly relates to a mooring model stiffness calibration device and a calibration measurement method for a mooring model in a pool test of an ocean engineering floating structure. Background Art

[0002] Currently, the most commonly used positioning system at sea is the mooring system. The characteristics of the mooring system include static characteristics and dynamic characteristics. For the simulation of dynamic characteristics, it is mainly achieved by considering the geometric parameters (such as diameter and length) and weight similarity of the mooring cable. The static characteristics reflect the stiffness characteristics of the mooring system, that is, the tension at the mooring end point changes with the position, which directly affects the accuracy of the test results. Therefore, the accuracy of the mooring static characteristic calibration directly affects the overall test accuracy.

[0003] In the existing model test technology, the mooring model stiffness calibration mostly uses tools such as simple fixed brackets, tension sensors, tape measures, and scales. The measurement method is as follows: Fix the mooring end anchor point, hang the mooring head on the bracket, determine the initial position of the bracket according to the horizontal and vertical distances between the mooring anchor point and the hanging point calculated by design and digital simulation, move the bracket to cause a horizontal displacement of the mooring hanging point, obtain multiple corresponding axial forces, measure the length of the mooring suspension section, calculate the horizontal force component from the catenary equation, and thus obtain the displacement-load characteristic curve of the mooring system. This measurement method has simple equipment, does not require complex test devices, and can be completed only by manual operation, and is suitable for model tests with only horizontal stiffness calibration requirements.

[0004] However, this measurement method also has some limitations:

[0005] (1) The measurement errors in each link are relatively large, and the data are mostly obtained by manual measurement, which is time-consuming and laborious;

[0006] (2) The adaptability of the measurement device is poor. In air and water, the horizontal and vertical calibration measurements require re-arranging the test device;

[0007] (3) The obtained displacement-load relationship is scatter data, and finally a curve needs to be fitted, and continuous measurement cannot be achieved.

[0008] The above problems will all reduce the accuracy of drawing the displacement-load characteristic curve of the mooring system and decrease the reliability of the test results.

[0009] Chinese Patent Application CN109839312A discloses a static stiffness calibration device for mooring cables in the air, including a vertical lead screw, a vertical frame, a wall fixing plate, a vertical slide, a horizontal frame, a horizontal slide, a horizontal ball screw, a servo motor and driver, a control cabinet, etc. The wall fixing plate is connected to the wall, and the fixing plate is fixedly connected to the vertical frame. A vertical slider is arranged on the vertical frame. One end of the lead screw is connected to the mounting bracket through a first bearing assembly, and the other end of the lead screw extends into the motor mounting seat and is connected to a second bearing assembly. The driving wheel shaft is connected to the lead screw through a transmission assembly. The horizontal frame is connected to the vertical slider. One end of the horizontal ball screw is connected to the horizontal frame through a first bearing assembly, and the other end of the horizontal ball screw extends into the motor mounting seat and is connected to a second bearing assembly. The driving wheel shaft is connected to the lead screw through a transmission assembly. A horizontal slider is arranged on the horizontal frame. When measuring the mooring model stiffness, this patent can realize the horizontal and vertical displacements of the mooring hanging point, and uses the motor and ball screw to complete the automated operation of the two-way displacement, improving the efficiency and accuracy of the mooring stiffness measurement. However, there are the following deficiencies: (1) The layout of the calibration device has great limitations, needs to be fixed on the wall or external support, and cannot realize the underwater mooring stiffness measurement; (2) The measuring device can only complete the stiffness calibration in the horizontal and vertical directions of the mooring, and cannot simulate the motion characteristics of the mooring under the yaw and roll of the platform.

[0010] Chinese Patent Application CN119023178A discloses a test device and method for the stiffness of a floating platform mooring system, including a floating platform model; at least three mechanical winches with retractable steel wires wound thereon; the other ends of multiple said steel wires are wound around guiding pulleys and then connected to the same side of the floating platform model; a tension sensor capable of measuring force is connected to the steel wire. This patent uses mechanical winches and steel wires to force the floating platform to move, and applies a six-degree-of-freedom gyroscope to identify the attitude of the floating platform, enabling the floating platform to move in a single degree of freedom, reducing the influence of multiple degrees of freedom, and improving the accuracy of mooring stiffness measurement. However, there are the following deficiencies: (1) Multiple mechanical winches need to be fixed on the same fixed platform, which has high requirements for the layout of the fixed platform, especially during underwater tests; (2) The tension sensor is arranged on the steel wire, and the mooring tension cannot be directly measured. When the steel wire forms an angle with the horizontal plane, an additional angle measuring device needs to be added; (3) For the simulation of the yaw and roll motions of the floating platform, the layout of the mechanical winches and the fixed platform needs to be reconsidered, and the measurement is relatively complex.

[0011] Chinese Invention Patent Application CN109696293A discloses a test device for vortex-induced motion in a deep-sea multi-column mooring floating platform, which includes a trailer, a longitudinal motion guide rail mechanism, a transverse motion guide rail mechanism, a yaw rotation mechanism, an optical measurement mechanism, and a top plate for installing a floating platform model. There is also a longitudinal elastic member for determining the longitudinal stiffness between the trailer and the transverse motion guide rail mechanism, a transverse elastic member for determining the transverse stiffness between the transverse motion guide rail mechanism and the yaw rotation mechanism, and an elastic constraint member for determining the rotational stiffness between the yaw rotation bracket and the connecting main shaft. This patent can simulate the longitudinal and lateral horizontal movements and yaw motion of the floating platform by using the guide rail mechanism, the yaw rotation mechanism and the connecting top plate. At the same time, the underwater translation and yaw motion of the floating platform can be simulated by mounting the test device on the trailer, providing conditions for the calibration of mooring stiffness. However, there are the following deficiencies: (1) Although the motion simulation of the floating platform is realized, additional measuring equipment is still required for the calibration of mooring stiffness, and the test device is relatively complex, increasing the measurement cost of mooring stiffness calibration; (2) It is impossible to simulate the motion characteristics of the mooring under the heave and roll of the platform.

[0012] In order to overcome these problems, there is an urgent need for a measuring device and scheme for calibrating the stiffness of a mooring model that can be applied to two-way and multi-scenario applications, and a special mechanical device is used for displacement and force loading and control to improve the scientific nature of the test method and the reliability of measurement data. Summary of the Invention

[0013] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a mooring model stiffness calibration device and a calibration measurement method, which can achieve continuous, two-way, automatic, and accurate measurement, thus meeting the requirements for mooring model stiffness calibration.

[0014] To achieve the above purpose, the present invention adopts the following technical solutions:

[0015] A mooring model stiffness calibration device includes a fixed frame. A frame guide rail is installed on the fixed frame, and a sliding frame capable of sliding along it is installed on the frame guide rail. A slide table guide rail is installed on the sliding frame, and a slider is installed on the slide table guide rail. The slider is fixedly connected to the slide table and can move along the slide table guide rail together; a laser displacement ranging sensor is installed on one side of the slide table, and a laser baffle corresponding to the laser displacement ranging sensor is installed at one end of the sliding frame; a first tension sensor and a rotatable measurement turntable are also installed on the slide table; a rope wheel mechanism corresponding to the measurement turntable is installed on the fixed frame; a second tension sensor and an inclination sensor are installed on the measurement turntable; the laser displacement ranging sensor, the first tension sensor, the second tension sensor, and the inclination sensor are all connected to a data collector through data lines, and the data collector is connected to a data processing and control system.

[0016] The upper part of the fixed frame is a square frame structure, which is installed on the folding telescopic legs through leg clamps, and universal wheels are installed at the bottom of the folding telescopic legs.

[0017] Frame guide rails are respectively installed on the left and right side frames of the square frame structure; a rope pulley mechanism is installed on the rear end frame of the square frame structure.

[0018] There are two sliding frames, which are respectively installed on the two frame guide rails through locking knobs, and a handle is connected to the front ends of the two sliding frames.

[0019] There are two slide table guide rails, which are respectively installed on the two sliding frames; there are two sliders, which are respectively stuck on the slide table guide rails and can be locked through locking knobs.

[0020] Guide rail end caps for preventing the sliders from derailing are respectively installed at both ends of the slide table guide rails.

[0021] There is one slide table, and its two ends are respectively fixedly installed on the two sliders.

[0022] A groove is formed in the slide table part located in the middle of the slide table guide rail, and the rotating shafts at both ends of the measuring turntable are installed in the groove through bearings. A positioning gear is installed at the end of the rotating shaft at one end, and a positioning key for restricting the rotation of the measuring turntable is arranged on the slide table and is matched with the positioning gear.

[0023] The rope pulley mechanism includes a servo motor installed on the rear end frame of the square frame structure. The output shaft of the servo motor is connected to the input shaft of the gearbox through a coupling. A rope pulley is installed on the input shaft of the gearbox, and a rope is wound around the rope pulley.

[0024] A turntable is installed on the output shaft of the gearbox, and cable guiding holes are arranged on the turntable.

[0025] A rope hole corresponding to the rope pulley is arranged on the first tension sensor.

[0026] The second tension sensor is installed in a slot on the measuring turntable, and a support plate is installed above the slot.

[0027] A calibration measurement method for a mooring model stiffness calibration device includes:

[0028] A. Measuring the sliding friction force:

[0029] Without installing the turntable, fixing the position and height of the stiffness calibration device, connecting the thin rope led out by the rope pulley to the first tension sensor, fixing the rope pulley so that it cannot rotate, pulling the handle, at this time the sliding frame slides relative to the fixed frame and the slide table, the slide table is stationary relative to the fixed frame under the traction of the thin rope, and the tension collected by the first tension sensor is the sliding friction force between the slider and the slide table guide rail;

[0030] B. Horizontal Stiffness Calibration of Mooring Model in Air: Without installing the turntable, fix the end anchor point of the mooring model, hang the head end of the mooring model on the second tension sensor, horizontally move the stiffness calibration device, adjust the telescopic legs to change the height of the stiffness calibration device, so that the horizontal distance and vertical distance between the mooring hanging point and the anchor point are consistent with the distances obtained from numerical simulation calculations; the data processing and control system controls the operation of the servo motor, the servo motor drives the rope pulley to make step-by-step or continuous rotation, and then uses the thin rope to drive the sliding table and the slider to slide step-by-step or continuously along the sliding table guide rail. The laser displacement ranging sensor and the laser baffle cooperate to measure the horizontal displacement of the mooring hanging point. At the same time, the first tension sensor measures the horizontal tension, the second tension sensor measures the axial tension of the mooring, and the inclination sensor measures the angle between the mooring axis and the horizontal direction; measure the corresponding displacement and axial force of the mooring model, calculate the horizontal force and vertical force of the mooring hanging point from the magnitude of the axial force of the mooring and the angle between the mooring axis and the horizontal direction, and finally draw the displacement-horizontal force characteristic curve of the mooring model to obtain the horizontal stiffness characteristic of the mooring model;

[0031] C. Vertical Stiffness Calibration of Mooring Model in Air: Without installing the turntable, vertically arrange the stiffness calibration device by rotating the folding telescopic legs, fix the end anchor point of the mooring model, hang the head end of the mooring model on the second tension sensor, horizontally move the stiffness calibration device, adjust the telescopic legs to change the height of the stiffness calibration device, so that the horizontal distance and vertical distance between the mooring hanging point and the anchor point are consistent with the distances obtained from numerical simulation calculations; the data processing and control system controls the operation of the servo motor, the servo motor drives the rope pulley to make step-by-step or continuous rotation, and then uses the thin rope to drive the sliding table and the slider to slide step-by-step or continuously along the sliding table guide rail. The laser displacement ranging sensor and the laser baffle cooperate to measure the vertical displacement of the mooring hanging point. At the same time, the first tension sensor measures the vertical tension, the second tension sensor measures the axial tension of the mooring, and the inclination sensor measures the angle between the mooring axis and the horizontal direction; measure the corresponding displacement and axial force of the mooring model, calculate the horizontal force and vertical force of the mooring hanging point from the magnitude of the axial force of the mooring and the angle between the mooring axis and the horizontal direction, and finally draw the displacement-vertical force characteristic curve of the mooring model to obtain the vertical stiffness characteristic of the mooring model;

[0032] D. Stiffness Calibration of Mooring Model in Water: The same as the stiffness calibration method of the mooring model in air, place the mooring model and the stiffness calibration device in the test pool, repeat the test in horizontal and vertical arrangements in turn, measure the horizontal and vertical stiffness characteristics of the mooring model in water, and no additional equipment and devices are required;

[0033] E. Simulating the Dynamic Response of Mooring under the Rolling and Yawing Motions of a Floating Structure: Install a turntable, remove the motor frame, slider, slide table, and measuring turntable plate. Fix the anchor point at the end of the mooring model. Connect the head end of the mooring model to the third tension sensor, and mount the third tension sensor on the fairlead hole of the turntable. Horizontally move the stiffness calibration device, and adjust the telescopic support legs to change the height of the stiffness calibration device so that the horizontal and vertical distances between the mooring hanging point and the anchor point are the same as those obtained from numerical simulation calculations. The data processing and control system controls the operation of the servo motor. The servo motor drives the turntable to rotate reciprocally in the plane. Use the third tension sensor to measure the axial tension of the mooring to achieve the simulation of the dynamic response of the mooring model under the rolling and yawing motions of the floating structure.

[0034] The beneficial effects of the present invention are as follows:

[0035] 1. The device has a compact and reasonable structure and is easy to operate. According to the requirements of mooring operation depth and displacement, the device can achieve lifting and automatic displacement, reducing human intervention.

[0036] 2. The measurement is accurate. Sensors are used to collect data, improving the accuracy and reliability of the data and eliminating the influence of human factors.

[0037] 3. It has a wide range of applications. This device can be used for calibrating the mooring stiffness in air and can also be placed in a water tank for calibrating the mooring stiffness in water. It can meet the displacement requirements in both horizontal and vertical directions. The device can also be used to simulate the dynamic response of the mooring under the rolling and yawing motions of the floating structure.

[0038] 4. The present invention uses a slide table and a tension sensor to improve the sliding friction measurement method, avoiding the human error of manually applying uniform motion to measure sliding friction, making the corrected measurement value more accurate. At the same time, the servo motor is used to achieve continuous displacement of the mooring point, and the displacement-load relationship obtained through data acquisition can more accurately reflect the characteristics of the mooring model. Description of the Drawings

[0039] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0040] Figure 2 It is a schematic diagram of the support part of the present invention;

[0041] Figure 3 It is a schematic diagram of the sliding part of the present invention;

[0042] Figure 4 It is a schematic diagram of the measurement part of the present invention;

[0043] Figure 5 It is a schematic diagram of the measurement part of the present invention with the support plate and inclination sensor removed;

[0044] Figure 6Schematic diagram for calibrating and measuring the horizontal stiffness of the mooring model in air according to the present invention;

[0045] Figure 7 Schematic diagram for calibrating and measuring the vertical stiffness of the mooring model in air according to the present invention;

[0046] Figure 8 Schematic diagram for arranging the simulation of the roll dynamic response of the floating structure according to the present invention;

[0047] Figure 9 Schematic diagram for arranging the simulation of the yaw dynamic response of the floating structure according to the present invention;

[0048] Figure 10 Schematic diagram of the data acquisition system according to the present invention;

[0049] Wherein, 1 - fixed frame, 2 - handle, 3 - sliding frame, 4 - slider, 5 - slide table, 6 - leg clip, 7 - folding telescopic leg, 8 - universal wheel, 9 - frame guide rail, 10 - servo motor, 11 - coupling, 12 - rope pulley, 13 - gearbox, 14 - turntable, 15 - laser baffle, 16 - slide table guide rail, 17 - laser displacement ranging sensor, 18 - guide rail end cap, 19 - bearing, 20 - measuring turntable, 21 - first tension sensor, 22 - rope hole, 23 - positioning key, 24 - positioning gear, 25 - support plate, 26 - inclination sensor, 27 - second tension sensor, 28 - data collector, 29 - computer mainframe, 30 - display. Specific embodiments

[0050] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0051] The structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limited conditions for the implementation of the present invention. Therefore, they do not have technical essential significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for the convenience of clear description and are not used to limit the scope for the implementation of the present invention. The change or adjustment of their relative relationships, without substantial change in the technical content, should also be regarded as the scope for the implementation of the present invention.

[0052] As Figures 1 - 10 shown, the mooring model stiffness calibration device includes a mooring model stiffness calibration device main body and a data acquisition and analysis system.

[0053] Among them, a frame guide rail 9 is installed on the fixed frame 1. The frame guide rail 9 and the fixed frame 1 are fixedly connected by hexagon socket head cap screws. A sliding frame 3 is fitted and installed on the frame guide rail 9. The end of the sliding frame 3 is connected to a handle 2 by a bolt. Pulling the handle 2 can make the sliding frame 3 slide along the frame guide rail 9. The position of the sliding frame 3 can be fixed by using the locking knob of the sliding frame 3. A slide guide rail 16 is installed on the sliding frame 3. The slide guide rail 16 and the sliding frame 3 are fixedly connected by hexagon socket head cap screws. A slider 4 is fitted and installed on the slide guide rail 16. The slider 4 and a slide 5 are fixedly connected by hexagon socket head cap screws. The slide 5 and the slider 4 can slide along the slide guide rail 16 together. The positions of the slider 4 and the slide 5 can be fixed by using the locking knob of the slider 4. Guide rail end caps 18 are installed at both ends of the slide guide rail 16 to prevent the slider 4 from derailing.

[0054] At the rear end of the fixed frame 1, a servo motor 10 and a gearbox 13 are arranged. The servo motor 10 and the gearbox 13 are connected by a coupling 11. The gearbox 13 has an input end and an output end. A rope pulley 12 is installed on the input rotating shaft, and a turntable 14 is installed at the output end. A cable guide hole is arranged on the turntable 14.

[0055] A groove is formed on the slide 5. Three bearings 19 and a positioning key 23 are correspondingly installed in the groove. The rotating shaft of the measuring turntable 20 is fitted and installed with the bearings 19. The measuring turntable 20 can rotate around the rotating shaft. A positioning gear 24 is installed at one end of the rotating shaft of the measuring turntable 20. The cooperation between the positioning gear 24 and the positioning key 23 on the slide 5 can limit the rotation of the measuring turntable 20. The first tension sensor 21 is fixed by hexagon socket head cap screws behind the rope hole 22. The second tension sensor 27 is fixed by hexagon socket head cap screws below the support plate 25. The inclination sensor 26 is fixed by hexagon socket head cap screws on the measuring turntable 20. The laser displacement ranging sensor 17 is installed on the left side of the slide 5. The laser baffle 15 is fixed by hexagon socket head cap screws at the front end of the left frame of the sliding frame 3.

[0056] There are four groups of folding telescopic legs 7 as supports below the fixed frame 1. The folding telescopic legs 7 and the leg clamping parts 6 are fixedly connected by hexagon socket head cap screws. The leg clamping parts 6 are clamped below the fixed frame 1. The folding telescopic legs 7 can be axially telescoped or fixed in position, and can also rotate within a right angle range along the rotating shaft through the arc-shaped notch mechanism. Universal wheels 8 are installed at the bottom of the folding telescopic legs 7. The universal wheels 8 can turn or be fixed in the horizontal plane.

[0057] The head end of the mooring model is hung on the second tension sensor 27. A thin rope led out from the rope pulley 12 on the input shaft of the gearbox is connected to the first tension sensor 21;

[0058] The laser displacement ranging sensor 17, the first tension sensor 21, the inclination sensor 26 and the second tension sensor 27 are all connected to the data collector 28 through data lines. The data collector 28 collects the analog signals output by the sensors, converts them into digital signals, and then transmits the digital signals to the computer host 29 to realize automatic continuous data acquisition and analysis. The computer host 29 is connected to the display 30.

[0059] The specific working process of the present invention is as follows:

[0060] Measuring the sliding friction: Without installing the turntable 14, fix the position and height of the stiffness calibration device. The thin rope led out by the rope pulley 12 is connected to the first tension sensor 21. Fix the rope pulley 12 so that it cannot rotate. Pull the handle 2. At this time, the sliding machine frame 3 slides relative to the fixed machine frame 1 and the sliding table 5. The sliding table 5 is stationary relative to the fixed machine frame 1 under the traction of the thin rope. The tension collected by the first tension sensor 21 is the sliding friction between the slider 4 and the sliding table guide rail 16.

[0061] Horizontal stiffness calibration of the mooring model in air: As Figure 6 , without installing the turntable 14, fix the end anchor point of the mooring model. The head end of the mooring model is hung on the second tension sensor 27. Horizontally move the stiffness calibration device and adjust the telescopic leg to change the height of the stiffness calibration device so that the horizontal distance and vertical distance between the mooring hanging point and the anchor point are consistent with the distances obtained by numerical simulation calculation; Give operation instructions through the human-machine interface of the console computer. Through serial communication, the PLC controller receives the control instructions and controls the operation of the servo motor 10. The servo motor 10 drives the rope pulley 12 to rotate step by step or continuously. Then, use the thin rope to drive the sliding table 5 and the slider 4 to slide step by step or continuously along the sliding table guide rail 16. The laser displacement ranging sensor 17 cooperates with the laser baffle 15 to measure the horizontal displacement of the mooring hanging point. At the same time, the first tension sensor 21 measures the horizontal tension, the second tension sensor 27 measures the mooring axial tension, and the inclination sensor 26 measures the angle between the mooring axis and the horizontal direction; Measure the corresponding displacement and mooring axial force of the mooring model. The horizontal force and vertical force of the mooring hanging point can be calculated from the magnitude of the mooring axial force and the angle between the mooring axis and the horizontal direction. Finally, draw the displacement-horizontal force characteristic curve of the mooring model to obtain the horizontal stiffness characteristic of the mooring model;

[0062] Vertical stiffness calibration of the mooring model in air: As Figure 7, without installing the turntable 14, vertically arrange the stiffness calibration device by rotating and folding the telescopic leg 7, fix the end anchor point of the mooring model, hang the head end of the mooring model on the second tension sensor 27, horizontally move the stiffness calibration device, adjust the telescopic leg to change the height of the stiffness calibration device, so that the horizontal distance and vertical distance between the mooring hanging point and the anchor point are consistent with the distances obtained from numerical simulation calculations. Give operation instructions through the human-machine interface of the console computer. Through serial communication, the PLC controller receives the control instructions and controls the servo motor 10 to work. The servo motor 10 drives the rope pulley 12 to rotate step by step or continuously. Then, use the thin rope to drive the sliding table 5 and the slider 4 to slide step by step or continuously along the sliding table guide rail 16. The laser displacement ranging sensor 17 cooperates with the laser baffle 15 to measure the vertical displacement of the mooring hanging point. At the same time, the first tension sensor 21 measures the vertical tension, the second tension sensor 27 measures the axial tension of the mooring, and the inclination sensor 26 measures the angle between the mooring axis and the horizontal direction; measure the corresponding displacement and axial force of the mooring model. From the magnitude of the mooring axial force and the angle between the mooring axis and the horizontal direction, the horizontal force and vertical force of the mooring hanging point can be calculated. Finally, draw the displacement-vertical force characteristic curve of the mooring model to obtain the vertical stiffness characteristic of the mooring model.

[0063] Stiffness calibration of the mooring model in water: The same as the stiffness calibration method of the mooring model in air, place the mooring model and the stiffness calibration device in the test pool, repeat the test in horizontal and vertical arrangements in sequence, measure the horizontal and vertical stiffness characteristics of the mooring model in water, and no additional equipment and devices are required.

[0064] Simulate the dynamic response of the mooring under the roll and yaw motions of the floating structure: As Figure 8 , Figure 9 , install the turntable 14, remove the sliding measurement part (including the sliding machine frame 3, slider 4, sliding table 5, measurement turntable 20, etc.), fix the end anchor point of the mooring model, connect the head end of the mooring model to the third tension sensor, and hang the third tension sensor on the fairlead hole of the turntable 14. Horizontally move the stiffness calibration device, adjust the telescopic leg to change the height of the stiffness calibration device, so that the horizontal distance and vertical distance between the mooring hanging point and the anchor point are consistent with the distances obtained from numerical simulation calculations; give operation instructions through the human-machine interface of the console computer. Through serial communication, the PLC controller receives the control instructions and controls the servo motor 10 to work. The servo motor 10 drives the turntable 14 to rotate reciprocally in the plane, and use the third tension sensor to measure the axial tension of the mooring to realize the simulation of the dynamic response of the mooring model under the roll and yaw motions of the floating structure; Figure 8 , Figure 9 They are the schematic diagrams of the roll and yaw simulation layouts respectively;

[0065] In summary, the mooring model stiffness calibration device for the marine engineering floating structure pool test proposed by the present invention can achieve continuous, two-way, automatic, and accurate measurement of the mooring model stiffness calibration.

[0066] Although the specific implementation manners of the present invention are described above in conjunction with the accompanying drawings, it is not a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications or deformations that can be made without creative labor on the basis of the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A mooring model stiffness calibration device, characterized in that It includes a fixed frame, on which a frame guide rail is installed. A sliding frame capable of sliding along it is installed on the frame guide rail. A slide table guide rail is installed on the sliding frame. A slider is installed on the slide table guide rail. The slider is fixedly connected to the slide table and can move along the slide table guide rail together. On one side of the slide table, a laser displacement ranging sensor is installed. On one end of the sliding frame, a laser baffle corresponding to the laser displacement ranging sensor is installed. A first tension sensor and a rotatable measuring turntable are also installed on the slide table. A rope pulley mechanism corresponding to the measuring turntable is also installed on the fixed frame. A second tension sensor and an inclination sensor are installed on the measuring turntable. The laser displacement ranging sensor, the first tension sensor, the second tension sensor and the inclination sensor are all connected to a data collector through data lines, and the data collector is connected to a data processing and control system. The rope pulley mechanism includes a servo motor installed on the rear end frame of a square frame structure. The output shaft of the servo motor is connected to the input shaft of a gearbox through a coupling. A rope pulley is installed on the input shaft of the gearbox, and a rope is wound around the rope pulley. A turntable is installed on the output shaft of the gearbox, and a cable guide hole is arranged on the turntable. A rope hole corresponding to the rope pulley is arranged on the first tension sensor. The second tension sensor is installed in a slot on the measuring turntable, and a support plate is installed above the slot. There are two slide table guide rails, which are respectively installed on two sliding frames. There are two sliders, which are respectively stuck on the slide table guide rails and can be locked by locking knobs. There is one slide table, and its two ends are respectively fixedly installed on two sliders. A groove is opened in the slide table part in the middle of the slide table guide rail. The rotating shafts at both ends of the measuring turntable are installed in the groove through bearings. A positioning gear is installed at the end of the rotating shaft at one end. A positioning key that can cooperate with the positioning gear to limit the rotation of the measuring turntable is arranged on the slide table.

2. The mooring model stiffness calibration device according to claim 1, characterized in that The upper part of the fixed frame is a square frame structure, which is installed on a folding telescopic leg through a leg clamping part. Universal wheels are installed at the bottom of the folding telescopic leg. Frame guide rails are respectively installed on the left and right side frames of the square frame structure. A rope pulley mechanism is installed on the rear end frame of the square frame structure.

3. The mooring model stiffness calibration device according to claim 1, characterized in that, There are two sliding frames, which are respectively installed on two frame guide rails through locking knobs. A handle is connected to the front ends of the two sliding frames.

4. The mooring model stiffness calibration device according to claim 1, characterized in that, Guide rail end caps for preventing the sliders from derailing are respectively installed at both ends of the slide table guide rail.

5. A calibration measurement method for the mooring model stiffness calibration device according to any one of claims 1-4, characterized in that, It includes: A. Measuring sliding friction: Do not install the turntable. Fix the position and height of the stiffness calibration device. The thin rope led out by the rope pulley is connected to the first tension sensor. Fix the rope pulley so that it cannot rotate. Pull the handle. At this time, the sliding frame slides relative to the fixed frame and the slide table. The slide table is stationary relative to the fixed frame under the traction of the thin rope. The tension collected by the first tension sensor is the sliding friction between the slider and the slide table guide rail. B. Horizontal Stiffness Calibration of the Mooring Model in Air: Without installing the turntable, fix the end anchor point of the mooring model, hang the head end of the mooring model on the second tension sensor, horizontally move the stiffness calibration device, adjust the telescopic legs to change the height of the stiffness calibration device, so that the horizontal distance and vertical distance between the mooring hanging point and the anchor point are consistent with the distances obtained from numerical simulation calculations; the data processing control system controls the servo motor to work, the servo motor drives the rope pulley to perform step-by-step or continuous rotation, and then uses the thin rope to drive the slide table and the slider to slide step-by-step or continuously along the slide table guide rail. The laser displacement ranging sensor and the laser baffle cooperate to measure the horizontal displacement of the mooring hanging point. At the same time, the first tension sensor measures the horizontal tension, the second tension sensor measures the axial tension of the mooring, and the inclination sensor measures the angle between the mooring axis and the horizontal direction; measure the corresponding displacement and axial force of the mooring model. The horizontal force and vertical force of the mooring hanging point can be calculated from the magnitude of the axial force of the mooring and the angle between the mooring axis and the horizontal direction. Finally, plot the displacement-horizontal force characteristic curve of the mooring model to obtain the horizontal stiffness characteristic of the mooring model; C. Vertical Stiffness Calibration of the Mooring Model in Air: Without installing the turntable, vertically arrange the stiffness calibration device by rotating the folding telescopic legs, fix the end anchor point of the mooring model, hang the head end of the mooring model on the second tension sensor, horizontally move the stiffness calibration device, adjust the telescopic legs to change the height of the stiffness calibration device, so that the horizontal distance and vertical distance between the mooring hanging point and the anchor point are consistent with the distances obtained from numerical simulation calculations; the data processing control system controls the servo motor to work, the servo motor drives the rope pulley to perform step-by-step or continuous rotation, and then uses the thin rope to drive the slide table and the slider to slide step-by-step or continuously along the slide table guide rail. The laser displacement ranging sensor and the laser baffle cooperate to measure the vertical displacement of the mooring hanging point. At the same time, the first tension sensor measures the vertical tension, the second tension sensor measures the axial tension of the mooring, and the inclination sensor measures the angle between the mooring axis and the horizontal direction; measure the corresponding displacement and axial force of the mooring model. The horizontal force and vertical force of the mooring hanging point can be calculated from the magnitude of the axial force of the mooring and the angle between the mooring axis and the horizontal direction. Finally, plot the displacement-vertical force characteristic curve of the mooring model to obtain the vertical stiffness characteristic of the mooring model; D. Stiffness Calibration of the Mooring Model in Water: The same as the stiffness calibration method of the mooring model in air, place the mooring model and the stiffness calibration device in the test pool, repeat the test in the horizontal and vertical arrangements in turn, and measure the horizontal and vertical stiffness characteristics of the mooring model in water without additional equipment and devices; E. Simulate the dynamic response of the mooring under the rolling and yawing motions of the floating structure: Install the turntable, remove the sliding machine frame, slider, sliding table, and measuring turntable module, fix the end anchor point of the mooring model, connect the first end of the mooring model to the third tension sensor, and mount the tension sensor on the fairlead hole of the turntable. Horizontally move the stiffness calibration device, adjust the telescopic support legs to change the height of the stiffness calibration device, so that the horizontal distance and vertical distance between the mooring hanging point and the anchor point are the same as those obtained from the numerical simulation calculation; the data processing control system controls the operation of the servo motor, the servo motor drives the turntable to rotate reciprocally in the plane, and the third tension sensor is used to measure the axial tension of the mooring to achieve the simulation of the dynamic response of the mooring model under the rolling and yawing motions of the floating structure.

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