Vertical wave load testing device and testing method thereof

Abstract

The present application relates to a kind of vertical wave load testing device and its testing method, belong to the field of hydrodynamics of floating structure.It includes pontoon main body, circular ring extension sheet body is arranged in the periphery of pontoon main body, and spacing unit is arranged between pontoon main body and circular ring extension sheet body;At least one test unit is installed in the inside of circular ring extension sheet body;The structure of single test unit is as follows: including the metal crossbar that is externally penetrated from the inside of pontoon main body into the inside of circular ring extension sheet body, one end of metal crossbar is located in the inside of pontoon main body, the other end is located in the middle position in the inside of circular ring extension sheet body, the end of metal crossbar in the inside of circular ring extension sheet body is movably connected with top rod in the lower side, the top of force sensor is connected with the bottom of top rod, the bottom of force sensor is installed on support, and support is fixed on the bottom surface in the inside of circular ring extension sheet body.The present application is symmetrically arranged, uses unidirectional force sensor to measure force cleanly and accurately, is not susceptible to the interference of transverse and rotary direction, and realizes the measurement of full wave direction.

Description

Technical Field

[0001] This invention relates to the field of hydrodynamics of floating structures, and in particular to a vertical wave load testing device and method. Background Technology

[0002] Ships and marine engineering structures encounter varying degrees of wind and wave environmental influences during offshore operations. Wave loads are the most significant, complex, and longest-lasting external loads. As sea conditions increase, these loads become fatal; if the hull or components cannot withstand them, extreme damage can occur, causing incalculable losses. For a long time, many scholars have been dedicated to wave load prediction research. With the continuous development of prediction technology and the demands of practical engineering, wave load prediction for small, critical components has gradually gained importance. Although numerical simulations can be used to obtain the surface fluid pressure of components and predict loads by integrating and superimposing gravity and inertial forces, the nonlinear characteristics of wind and wave environments present accuracy and verification challenges. Therefore, model testing remains the most effective and intuitive research approach. However, due to the relatively small size of key components in ships and marine engineering, which differ from the main body by several times, and are interconnected and influence each other, there are many difficulties and challenges in model testing. These are mainly reflected in the following aspects: 1. The gap between the circular main body and the circular appendage is small, and the entire circumference is constrained. Under the action of waves, there is a time difference between the positive and negative wave loads on the circular appendage, and the front and rear loads are in opposite directions, generating torque. This may cause the circular appendage and the main body to interfere with each other. Therefore, it is difficult to design a test device that can measure in all wave directions and avoid interference between the main body and the circular appendage; 2. After being affected by waves, the circular appendage will generate loads in multiple directions, including vertical, lateral, and rotational, which also affect each other. It is crucial to accurately capture the vertical wave load.

[0003] Currently, most research focuses on wave loads on the main body of large ships or marine equipment, primarily using numerical methods. Model testing utilizes a combination of segmented models and steel beam structures, a relatively mature technique. However, with technological advancements, increasing attention is being paid to wave loads on smaller-scale appendages. Summary of the Invention

[0004] To address the shortcomings of existing production technologies, the applicant provides a vertical wave load testing device and method, thereby enhancing the wave load testing capabilities for small-scale appendages, solving the problem of accurate load measurement for small-scale appendages in wave environments on marine engineering equipment, providing technical support for the design of small-scale appendage connection structures, and promoting the development of ship hydrodynamic technology.

[0005] The technical solution adopted in this invention is as follows: A vertical wave load testing device includes a float body, an annular extension plate is added to the periphery of the float body, and a limiting unit is set between the float body and the annular extension plate; at least one testing unit is installed inside the annular extension plate; the structure of a single testing unit is as follows: it includes a metal crossbar that penetrates outward from the inside of the float body and enters the inside of the annular extension plate, one end of the metal crossbar is located inside the float body, and the other end of the metal crossbar is located in the middle of the annular extension plate, the end of the metal crossbar located inside the annular extension plate is movably connected to a top rod below, the bottom of the top rod is connected to the top of a force sensor, the bottom of the force sensor is mounted on a support, and the support is fixed on the bottom surface of the annular extension plate.

[0006] As a further improvement to the above technical solution:

[0007] Preferably, the structure of the limiting unit includes: a U-shaped convex guide fixed on the float body and a U-shaped concave guide sleeve fixed on the annular extension plate, wherein the U-shaped convex guide is inserted into the U-shaped concave guide sleeve.

[0008] Preferably, a pre-embedded plate is also provided at the contact end between the metal crossbar and the inner wall of the float body.

[0009] Preferably, a nut is fitted at one end of the metal crossbar inside the float body, and the nut abuts against the embedded plate.

[0010] Preferably, a copper sleeve is provided at the connection end between the metal crossbar and the top rod, and a cylindrical pin is provided at the contact end between the copper sleeve and the top rod.

[0011] Preferably, the support is assembled to the bottom surface of the annular extension plate by screws.

[0012] A test method for a vertical wave load testing device includes the following steps:

[0013] Step 1: Make the main body of the pontoon and the circular extension plate separately. Make holes at 90° intervals at the orthogonal positions on the main body of the pontoon and match the pre-embedded supports at the corresponding positions on the circular extension plate.

[0014] Step 2: Match the pre-embedded plate at each opening on the inner wall of the pontoon body to form 4 pre-embedded plates at orthogonal positions. A metal crossbar is fixedly installed on each pre-embedded plate by a nut.

[0015] Step 3: Install the force sensor on the support pre-embedded inside the circular extension plate, and connect the force sensor to the metal crossbar in Step 2 through the top rod at the top. The contact ends are respectively equipped with copper sleeves and cylindrical pins.

[0016] Step 4: Fix a U-shaped convex guide on the main body of the pontoon and a U-shaped concave guide sleeve on the circular extension plate. Insert the U-shaped convex guide into the U-shaped concave guide sleeve to form a limit, thereby constraining the relative rotational movement between the main body of the pontoon and the circular extension plate in the horizontal direction.

[0017] Step 5: Constrain the main body of the float and apply different loads at the center of the circular extension plate to obtain the verification coefficients of the force sensor at different positions;

[0018] Step 6: Let the entire device float freely in still water, and record the initial voltage signals of the force sensors in each direction, and calculate the initial vertical force.

[0019] Step 7: Use the wave-generating equipment in the wave pool to generate waves. At this time, the entire device will generate six degrees of freedom of motion. Simultaneously, the waves will generate a load on the circular extension plate. At this time, collect the voltage change values ​​of the force sensors in each direction to obtain the corresponding vertical forces. Finally, calculate the total vertical resultant force.

[0020] Preferably, the support pre-embedded at the corresponding position of the annular extension plate in step one is assembled by screws.

[0021] Preferably, in step four, the mating position of the U-shaped concave guide sleeve and the U-shaped convex guide is located at an angle of 45°.

[0022] The beneficial effects of this invention are as follows:

[0023] The present invention has a compact and reasonable structure and is easy to operate. By adding a circular extension plate to the periphery of the float body and setting a test unit inside the circular extension plate, the omnidirectional wave measurement can be achieved through multiple sets of test units arranged in an orthogonal state.

[0024] The present invention also has the following advantages:

[0025] (1) The entire testing device of the present invention is simple and adopts a symmetrical arrangement structure, which makes the unidirectional force sensors in multiple test units measure force cleanly and accurately, and are not easily affected by interference in the lateral and rotational directions.

[0026] (2) The U-shaped concave guide sleeve and U-shaped convex guide of the present invention effectively form a limiting and guiding mechanism, which can constrain the lateral and rotational movement between the float body and the circular extension plate, release the vertical movement, and effectively ensure the accuracy of the testing device. Attached Figure Description

[0027] Figure 1 This is a top view of the overall structure of the present invention.

[0028] Figure 2 This is a schematic diagram of the connection structure between the float body and the annular extension plate of the present invention.

[0029] Figure 3 This is a schematic diagram of the specific structure of the test unit of the present invention.

[0030] Figure 4 This is a schematic diagram of the present invention in a test state.

[0031] The components include: 1. Float body; 2. Circular extension plate; 3. U-shaped concave guide sleeve; 4. U-shaped convex guide; 5. Test unit;

[0032] 501. Embedded plate; 502. Metal crossbar; 503. Nut; 504. Copper sleeve; 505. Cylindrical pin; 506. Top rod; 507. Force sensor; 508. Support; 509. Screw. Detailed Implementation

[0033] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0034] like Figures 1-4 As shown, the vertical wave load testing device of this embodiment includes a float body 1, an annular extension plate 2 is provided around the float body 1, and a limiting unit is provided between the float body 1 and the annular extension plate 2; at least one test unit 5 is installed inside the annular extension plate 2; the structure of a single test unit 5 is as follows: it includes a metal crossbar 502 that penetrates from the inside of the float body 1 outward and enters the annular extension plate 2, one end of the metal crossbar 502 is located inside the float body 1, and the other end of the metal crossbar 502 is located in the middle position inside the annular extension plate 2, and the end of the metal crossbar 502 located inside the annular extension plate 2 is movably connected to a top rod 506 below, the bottom of the top rod 506 is connected to the top of a force sensor 507, the bottom of the force sensor 507 is installed on a support 508, and the support 508 is fixed on the bottom surface inside the annular extension plate 2.

[0035] In this embodiment, the structure of the limiting unit includes: a U-shaped convex guide 4 fixed on the float body 1 and a U-shaped concave guide sleeve 3 fixed on the annular extension plate 2, wherein the U-shaped convex guide 4 is inserted into the U-shaped concave guide sleeve 3.

[0036] In this embodiment, a pre-embedded plate 501 is also added to the contact end between the metal crossbar 502 and the inner side wall of the float body 1.

[0037] In this embodiment, a nut 503 is fitted onto one end of the metal crossbar 502 located inside the float body 1, and the nut 503 abuts against the embedded plate 501.

[0038] In this embodiment, a copper sleeve 504 is provided at the connection end between the metal crossbar 502 and the top rod 506, and a cylindrical pin 505 is provided at the contact end between the copper sleeve 504 and the top rod 506.

[0039] In this embodiment, the support 508 is assembled with the bottom surface of the annular extension plate 2 by screws 509.

[0040] like Figure 4 As shown, the testing method of the vertical wave load testing device in this embodiment includes the following steps:

[0041] Step 1: Make the main body of the float 1 and the annular extension plate 2 respectively. Make holes at 90° intervals at the orthogonal positions on the main body of the float 1, and match the pre-embedded support 508 at the corresponding position on the annular extension plate 2. The pre-embedded support 508 at the corresponding position on the annular extension plate 2 is assembled by screws 509.

[0042] Step 2: Match the pre-embedded plate 501 at each opening on the inner side wall of the float body 1 to form 4 pre-embedded plates 501 at orthogonal positions. A metal crossbar 502 is fixedly installed on each pre-embedded plate 501 by a nut 503.

[0043] Step 3: Install the force sensor 507 on the support 508 pre-embedded inside the annular extension plate 2. At the same time, connect the force sensor 507 to the metal crossbar 502 in Step 2 through the top rod 506 at the top. The contact ends are respectively provided with copper sleeve 504 and cylindrical pin 505.

[0044] Step 4: Fix the U-shaped convex guide 4 on the main body of the float 1, fix the U-shaped concave guide sleeve 3 on the circular extension plate 2, and insert the U-shaped convex guide 4 into the U-shaped concave guide sleeve 3 to form a limit. The mating position of the U-shaped concave guide sleeve 3 and the U-shaped convex guide 4 is located at an angle of 45°, thereby constraining the relative rotational movement between the main body of the float 1 and the circular extension plate 2 in the horizontal direction.

[0045] Step 5: Constrain the main body of the float 1, and apply different loads at the center of the annular extension plate 2 to obtain the verification coefficient k of the force sensor 507 at different positions. i (i = 1 to 4);

[0046] Step Six: Let the entire device float freely in still water, and simultaneously record the initial voltage signal V of the force sensor 507 in each direction. 0i (i = 1 to 4), and according to F 0i =k i V 0i (i = 1 to 4);

[0047] Step 7: Generate waves using the wave-generating equipment in the wave pool;

[0048] The wave equation is: η = η a cos(ω w t+ε);

[0049] At this point, the entire device will generate six degrees of freedom of motion, and the wave will exert a load on the annular extension plate 2.

[0050] Voltage changes of force sensors 507 in all directions: V i =V ai cos(ω w t+β wi ), (i = 1 to 4); thus obtaining the corresponding vertical forces: F i =k i [V ai cos(ω w t+β wi )-V 0i ], (i = 1~4); finally, calculate the total vertical resultant force:

[0051] The present invention adds a circular extension plate 2 around the buoy body 1, and uses a U-shaped convex guide 4 and a U-shaped concave guide sleeve 3 to constrain the relative rotational movement between the buoy body 1 and the circular extension plate 2 in the horizontal direction, thereby reducing the interference in the lateral and rotational directions and making the test results more accurate. At the same time, a test unit 5 is set inside the circular extension plate 2. Through multiple sets of test units 5 arranged in an orthogonal state, omnidirectional wave measurement is realized.

[0052] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. A vertical wave load testing device, characterized in that: Includes a float body (1), and an annular extension plate (2) is added to the periphery of the float body (1), and a limiting unit is provided between the float body (1) and the annular extension plate (2); At least one test unit (5) is installed inside the annular extension sheet (2); The structure of a single test unit (5) is as follows: it includes a metal crossbar (502) that extends outward from the inside of the float body (1) and enters the inside of the annular extension plate (2). One end of the metal crossbar (502) is located inside the float body (1), and the other end of the metal crossbar (502) is located in the middle of the annular extension plate (2). The end of the metal crossbar (502) located inside the annular extension plate (2) is movably connected to a top rod (506) below. The bottom of the top rod (506) is connected to the top of a force sensor (507). The bottom of the force sensor (507) is mounted on a support (508), and the support (508) is fixed on the bottom surface inside the annular extension plate (2). The structure of the limiting unit includes: a U-shaped convex guide (4) fixed on the float body (1) and a U-shaped concave guide sleeve (3) fixed on the circular extension plate (2), wherein the U-shaped convex guide (4) is inserted into the U-shaped concave guide sleeve (3); The entire device was floated freely in still water, and the initial voltage signals of the force sensors (507) in each direction were recorded, and the initial vertical force was calculated. Waves are generated using wave-generating equipment in a wave pool. At this time, the entire device will generate six degrees of freedom of motion. Simultaneously, the waves will generate a load on the circular extension plate (2). At this time, the voltage change values ​​of the force sensors (507) in each direction are collected to obtain the corresponding vertical forces. Finally, the total vertical resultant force is calculated.

2. The vertical wave load testing device as described in claim 1, characterized in that: An embedded plate (501) is also added to the contact end between the metal crossbar (502) and the inner wall of the float body (1).

3. The vertical wave load testing device as described in claim 1, characterized in that: The metal crossbar (502) is fitted with a nut (503) at one end inside the float body (1), and the nut (503) abuts against the embedded plate (501).

4. The vertical wave load testing device as described in claim 1, characterized in that: A copper sleeve (504) is provided at the connection end between the metal crossbar (502) and the top rod (506), and a cylindrical pin (505) is provided at the contact end between the copper sleeve (504) and the top rod (506).

5. The vertical wave load testing device as described in claim 1, characterized in that: The support (508) is assembled to the bottom surface of the annular extension plate (2) by screws (509).

6. A test method for a vertical wave load testing device, characterized in that: Includes the following steps: Step 1: Make the main body of the float (1) and the circular extension plate (2) respectively. Make holes at 90° intervals at the orthogonal positions on the main body of the float (1) and match the pre-embedded support (508) at the corresponding position on the circular extension plate (2). Step 2: Match the pre-embedded plate (501) at each inner side wall opening of the float body (1) to form 4 pre-embedded plates (501) at orthogonal positions. A metal crossbar (502) is fixedly installed on each pre-embedded plate (501) by a nut (503). Step 3: Install a force sensor (507) on the support (508) pre-embedded inside the circular extension plate (2), and connect the force sensor (507) to the metal crossbar (502) in Step 2 through the top rod (506) at the top. The contact ends are respectively provided with copper sleeve (504) and cylindrical pin (505). Step 4: Fix the U-shaped convex guide (4) on the main body of the float (1), fix the U-shaped concave guide sleeve (3) on the circular extension plate (2), and insert the U-shaped convex guide (4) into the U-shaped concave guide sleeve (3) to form a limit, thereby constraining the relative rotational movement between the main body of the float (1) and the circular extension plate (2) in the horizontal direction; Step 5: Constrain the main body of the float (1), apply different loads at the center of the circular extension plate (2), and obtain the verification coefficients of the force sensor (507) at different positions respectively; Step 6: Let the entire device float freely in still water, and record the initial voltage signals of the force sensors (507) in each direction, and calculate the initial vertical force; Step 7: Use the wave-generating equipment in the wave pool to generate waves. At this time, the entire device will generate six degrees of freedom of motion. At the same time, the waves will generate a load on the circular extension plate (2). At this time, collect the voltage change values ​​of the force sensors (507) in each direction to obtain the corresponding vertical forces. Finally, calculate the total vertical resultant force.

7. The test method of the vertical wave load testing device as described in claim 6, characterized in that: The support (508) pre-embedded at the corresponding position of the annular extension plate (2) in step one is assembled by screws (509).

8. The test method of the vertical wave load testing device as described in claim 6, characterized in that: In step four, the U-shaped concave guide sleeve (3) and the U-shaped convex guide (4) are positioned at an angle of 45°.

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