Drop test release device and method adapted to specific tooling configurations

Abstract

The application relates to a falling body test smooth release device and method suitable for specific tool structures, which comprises a tool base frame, a cantilever beam extending from the top of the tool base frame, a release connecting piece assembled on the cantilever beam, a to-be-tested ice body assembly assembled at the bottom end of the release connecting piece, the to-be-tested ice body assembly comprising an ice body clamp, a matching area reserved on the ice body clamp, a matching weight movably assembled on the matching area, a reinforced test plate correspondingly arranged below the release connecting piece, a sensor group installed on the reinforced test plate, and a test system connected with the sensor group. The application simulates a ship body in navigation by using the test plate, and simulates an ice block in an ice area by using a free-falling ice block, so that the simulation conditions of the collision between a ship bow and a large layer ice in the collision type ice breaking, the collision between a ship bow and a large layer ice in the continuous ice breaking mode of a ship, and the collision between a ship and a floating ice in the navigation of a ship in a broken ice area are obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of drop test, and in particular to a drop test smooth release device and method adapted to a specific tooling structure. Background Art

[0002] When a ship sails in an ice area, it will be subject to ice loads. There are various ship-ice interaction modes, such as the collision between the bow of the ship and large ice layers when the ship adopts the collision icebreaking method, the collision between the bow of the ship and large ice layers when the ship adopts the continuous icebreaking method, and the collision between the ship and floating ice when sailing in the broken ice area.

[0003] Impact icebreaking utilizes the kinetic energy of a ship's collision to break up layers of ice. This requires the ship to collide with the ice at a certain speed, subjecting the ship to impact loads from the ice. This ship-ice interaction mode is the primary icebreaking mode for ships operating in ice-covered areas. Therefore, a study of the local bow structure was conducted, with numerical simulations performed on the structural dynamic response to vertical ice impact on the bow shoulder. To verify its engineering applicability, free-fall ice impact tests were conducted to validate the numerical simulation method.

[0004] During the model test, it is difficult to ensure the stability of the initial position and angle of the ice body release if the traditional release method is used, which is more difficult than the numerical simulation method. Summary of the Invention

[0005] In response to the shortcomings in the above-mentioned existing production technology, the applicant provides a rationally structured smooth release device and method for fall test that is adapted to a specific tooling structure. The release height of the ice body can be freely adjusted, and the ice body can be released smoothly during a free fall test, so that there is no initial velocity and deflection angle. The structural form, installation and debugging methods of all devices are also provided.

[0006] The technical solutions adopted in the present invention are as follows:

[0007] A drop test smooth release device adapted to a specific tooling structure comprises a tooling base frame, a cantilever beam extending from the top of the tooling base frame, a release connector mounted on the cantilever beam, and an ice assembly to be tested mounted at the bottom of the release connector.

[0008] The ice body assembly to be tested includes an ice body fixture, a loading area is reserved on the ice body fixture, and a counterweight block is movably installed in the loading area.

[0009] A reinforced test plate is correspondingly provided below the release connector, a sensor group is installed on the reinforced test plate, and the sensor group is connected to a test system.

[0010] As a further improvement of the above technical solution:

[0011] The release connector is provided with a plurality of mounting holes in the vertical direction, and the mounting holes are fastened to the cantilever beam.

[0012] The release connector is connected to the ice body clamp via a release bolt or an electromagnetic device.

[0013] The ice body clamp includes a limiting plate, and a plurality of fixing holes are formed on the limiting plate;

[0014] A first rib is vertically provided above the limit plate, and a second rib is located on the top of the first rib and parallel to the limit plate. A mounting plate coplanar with the release connector is formed on the side of the second rib facing away from the first rib, and the release bolt or electromagnetic device is located between the release connector and the mounting plate.

[0015] A positioning plate is vertically provided at the bottom end of the release connector. When the mounting plate is connected to the release connector, the positioning plate is in contact with the second rib plate.

[0016] The loading area is the entire surface of the limit plate.

[0017] A test method using a drop test smooth release device adapted to a specific tooling structure comprises the following steps:

[0018] Strain sensors, pressure sensors, and displacement sensors are arranged on the test board and connected to the test system.

[0019] Fix the test board to the bottom of the tooling base.

[0020] Connect the arranged strain sensors, pressure sensors, and displacement sensors to the test system.

[0021] Estimate the falling height of the test target and fix the release connector to the cantilever beam of the tooling base according to the estimated height position.

[0022] Install the ice assembly to be tested onto the release connection device.

[0023] According to the installed tooling structure and the degree of melting of the ice assembly to be tested, weights are added to the loading area to adjust the center of gravity of the entire falling system so that the center of gravity is stable and located in the middle. A laser rangefinder is used to determine the initial position of the falling system.

[0024] Connect the strain sensor, pressure sensor, displacement sensor and external camera system to the computer of the test system and perform zero initialization.

[0025] After confirming that all equipment is working properly, set the sampling frequency to 5000Hz, start the data acquisition system, and record the time domain signals of relevant parameters. After recording the test data for at least 1 minute, release the falling system and let it collide with the test board.

[0026] After the falling object collision is completed and the test parameters are stable, the falling object height is changed to conduct multiple tests to obtain multiple sets of parameters.

[0027] After the test is completed, stop data collection, turn off all instruments, and dismantle the test model.

[0028] As a further improvement of the above technical solution:

[0029] The ice block body of the ice block assembly to be tested is a whole frozen ice block. A connecting piece is frozen in the ice block body, and the connecting piece passes through a fixing hole on the limiting plate to achieve connection.

[0030] When the falling system is in its initial state, both the initial velocity and the deflection angle are 0.

[0031] The beneficial effects of the present invention are as follows:

[0032] The present invention uses a test plate to simulate a hull in navigation and uses free-falling ice blocks to simulate ice blocks in an ice zone, thereby obtaining simulations of the collision between the bow of a ship and a large layer of ice during impact icebreaking, the quasi-static extrusion between the bow of a ship and a large layer of ice when a ship adopts a continuous icebreaking method, the collision between a ship and floating ice when sailing in a broken ice zone, and the freezing and extrusion of sea ice when a ship is trapped in an ice zone due to special reasons.

[0033] In the present invention, before free fall, the ice assembly to be tested is required to have no initial velocity and deflection angle. Therefore, a rigid structure is used to restrain the ice assembly to be tested, which is different from the conventional rope lifting structure and can ensure the stability of the ice body in the initial stage of release.

[0034] Since ice cubes may melt out of position during transportation and waiting, the present invention provides the ice clamp with a platform for assembling counterweights on the basis of clamping and limiting the ice cubes. The counterweights can supplement the melted parts of the ice body and increase the weight of the falling system.

[0035] The melting of ice is uncertain, so no specific area is set as the loading area on the limit plate that can clamp the ice. Instead, the entire limit plate can be counterweighted to meet the balance requirements.

[0036] After the test system of the present invention obtains multiple sets of drop test data, numerical simulation can verify the engineering applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0038] Figure 2 This is a schematic diagram of the release connector structure of the present invention.

[0039] Figure 3 It is a schematic diagram of the ice body clamp structure of the present invention.

[0040] Wherein: 1. tooling base frame; 2. cantilever beam; 3. release connector; 4. ice body assembly to be tested; 5. ice body fixture; 6. test plate;

[0041] 301, mounting hole; 302, release bolt or electromagnetic device; 303, positioning plate;

[0042] 501, limit plate; 502, fixing hole; 503, first rib plate; 504, second rib plate; 505, mounting plate. DETAILED DESCRIPTION

[0043] The specific embodiments of the present invention will be described below with reference to the accompanying drawings.

[0044] like Figure 1-3 As shown, the drop test smooth release device adapted to a specific tooling structure of this embodiment includes a tooling base frame 1, a cantilever beam 2 extending from the top of the tooling base frame 1, a release connector 3 mounted on the cantilever beam 2, and an ice assembly 4 to be tested mounted at the bottom end of the release connector 3.

[0045] The ice body assembly 4 to be tested includes an ice body fixture 5, on which a loading area is reserved, and a counterweight block is movably mounted.

[0046] A reinforced test plate 6 is correspondingly provided below the release connector 3 , and a sensor group is mounted on the reinforced test plate 6 , and the sensor group is connected to a test system.

[0047] The release connector 3 is provided with a plurality of mounting holes 301 in the vertical direction, and the mounting holes 301 are fastened to the cantilever beam 2 .

[0048] The release connector 3 and the ice body clamp 5 are connected via a release bolt or an electromagnetic device 302 .

[0049] The ice body clamp 5 includes a limiting plate 501 , and a plurality of fixing holes 502 are formed on the limiting plate 501 ;

[0050] A first rib 503 is vertically provided above the limiting plate 501, and a second rib 504 is located on the top of the first rib 503 and parallel to the limiting plate 501. A mounting plate 505 coplanar with the release connector 3 is formed on the side of the second rib 504 facing away from the first rib 503, and the release bolt or electromagnetic device 302 is located between the release connector 3 and the mounting plate 505.

[0051] A positioning plate 303 is vertically provided at the bottom end of the release connector 3 . When the mounting plate 505 is connected to the release connector 3 , the positioning plate 303 is in contact with the second rib plate 504 .

[0052] The loading area is the entire surface of the limiting plate 501.

[0053] The test method of this embodiment using a drop test smooth release device adapted to a specific tooling structure includes the following steps:

[0054] Strain sensors, pressure sensors, and displacement sensors are arranged on the test board 6, and the above sensors are connected to the test system.

[0055] Fix the test board 6 to the bottom of the tooling base 1,

[0056] Connect the arranged strain sensors, pressure sensors, and displacement sensors to the test system.

[0057] Estimate the falling height of the test target and fix the release connector 3 on the cantilever beam 2 of the tooling base 1 according to the estimated height position.

[0058] Install the ice body assembly 4 to be tested onto the release connection device,

[0059] According to the installed tooling structure and the degree of melting of the ice assembly 4 to be tested, weight blocks are added to the loading area to adjust the center of gravity of the entire falling system so that the center of gravity is stable and located in the middle; and a laser rangefinder is used to determine the initial position of the falling system.

[0060] Connect the strain sensor, pressure sensor, displacement sensor and external camera system to the computer of the test system and perform zero initialization.

[0061] After confirming that all equipment is working properly, set the sampling frequency to 5000Hz, start the data acquisition system, and record the time domain signals of relevant parameters. After recording the test data for at least 1 minute, release the falling system and let it collide with the test board 6.

[0062] After the falling object collision is completed and the test parameters are stable, the falling object height is changed to conduct multiple tests to obtain multiple sets of parameters.

[0063] After the test is completed, stop data collection, turn off all instruments, and dismantle the test model.

[0064] The ice block body of the ice block assembly 4 to be tested is a whole frozen ice block. A connector is frozen in the ice block body. The connector passes through the fixing hole 502 on the limiting plate 501 to achieve connection.

[0065] When the falling system is in its initial state, both the initial velocity and the deflection angle are 0.

[0066] The specific structure and working principle of the present invention are as follows:

[0067] like Figure 1 As shown, a cantilever beam 2 is vertically mounted on the tooling base 1, and a release connector 3 is mounted on the end of the cantilever beam 2. The specific structure of the release connector 3 is shown in FIG. Figure 2The main body is a vertical plate with linear array mounting holes 301 on it, and the release connector 3 is installed on the cantilever beam 2 through connectors such as bolts and pins.

[0068] A positioning plate 303 is vertically provided at the bottom of the release connector 3. An end of the release connector 3 close to the positioning plate 303 is provided with a structure for reserving an internal plug-in space so that Figure 3 The mounting plate 505 is inserted into the plug-in space. After the plug-in is completed, it is connected and locked by fasteners. Figure 2 The middle positioning plate 303 and Figure 3 The second rib 504 is fitted to increase the connection area and improve the connection strength.

[0069] like Figure 3 The figure shows the structure of the ice fixture 5 according to the present invention. The retaining plate 501, with multiple fixing holes 502, secures the ice cube body below and allows for the addition of counterweights above. To simulate large ice cubes, whole frozen ice is used whenever possible; this also reduces melting speed. A connecting member, such as a rope, frozen in the ice cube body, is inserted upward through the fixing holes 502 to retain the ice cube in place.

[0070] During the test, the present invention first installs strain sensors, pressure sensors, and displacement sensors on the bottom surface of the test plate 6. These sensors are flat on the bottom of the test plate 6 to simulate the hull. In conventional tests, dynamic objects are often used to simulate the hull of a ship in motion. In the present invention, in order to ensure the stability of relative motion, test accuracy, and reduce the difficulty of the test, the relative motion of the hull and the ice block is reversed, so that the hull is stationary and the ice block is in motion. With this design, the vertical drop of the ice block simulates the horizontal direction of the hull in sailing, the inertia of the ice block simulates the inertia of the hull in sailing, and the horizontal arrangement of the test plate 6 simulates the hull tending to be vertical during sailing. This is equivalent to flipping the actual sailing situation 90 degrees, which can restore the actual sailing situation as much as possible.

[0071] After the sensor is installed, the test board 6 is fixed on the tooling base 1 , corresponding to the position directly below the end of the cantilever beam 2 .

[0072] Connect the arranged strain sensors, pressure sensors, and displacement sensors to the test system through leads;

[0073] Based on the estimated falling height of the test target, the cantilever beam 2 release device is fixed to the specific tooling structure by bolts according to the estimated height position;

[0074] Install the release connection device on the cantilever beam 2 release device by bolts;

[0075] Use a release bolt or an electromagnetic release device to install the ice body assembly 4 to be tested with the ice body on the release connection device;

[0076] Based on the specific fixture structure, the center of gravity of the entire ice body assembly 4 to be tested is adjusted, and a counterweight is added to the limit plate 501 to keep the entire ice body assembly 4 to be tested balanced. A laser rangefinder is used to determine the initial position of the falling body system.

[0077] Connect the strain sensor, pressure sensor, displacement sensor and camera system to the computer and perform zero reset and initialization;

[0078] Confirm that all equipment is working properly;

[0079] Set the sampling frequency to 5000 Hz, start the data acquisition system, and record the time domain signals of relevant parameters. After recording the test data for 1 minute, open the release bolt or electromagnetic release device to allow the ice assembly 4 to fall freely.

[0080] After the ice assembly 4 to be tested falls, the collision is completed, and the test parameters are stabilized, subsequent tests at different drop heights are carried out until the expected test data is obtained;

[0081] After completing the ice body falling impact test, stop the test data collection, turn off all instruments, and dismantle the test model.

[0082] The present invention verifies the numerical simulation method of the free fall test of ice body and structural collision test. The ice body can be conveniently fixed to the test ice body suspension device. The ice body can be released smoothly during the free fall test without initial velocity and deflection angle. The release height of the ice body can be arbitrarily adjusted to meet the test requirements.

[0083] The above description is an explanation of the present invention, not a limitation of the present invention. The scope of the present invention is defined in the claims. Any modifications may be made within the scope of protection of the present invention.

Claims

1. A test method for a drop test smooth release device adapted to a specific tooling structure, characterized by: The falling body test smooth release device comprises a tool base frame (1), a cantilever beam (2) extending from the top of the tool base frame (1), a release connector (3) mounted on the cantilever beam (2), and an ice body assembly (4) to be tested mounted at the bottom end of the release connector (3). The ice body assembly (4) to be tested comprises an ice body fixture (5), a loading area is reserved on the ice body fixture (5), and a counterweight block is movably mounted on the loading area. A test board (6) is correspondingly provided below the release connector (3), and a sensor group is installed on the test board (6). The sensor group is connected to a test system. The test method includes the following steps: Strain sensors, pressure sensors, and displacement sensors are arranged on the test board (6), and the above sensors are connected to the test system. Fix the test plate (6) to the bottom of the tooling base (1). Connect the arranged strain sensors, pressure sensors, and displacement sensors to the test system. Estimate the falling height of the test target, and according to the estimated height position, fix the release connector (3) on the cantilever beam (2) of the tooling base (1). Install the ice body assembly (4) to be tested onto the release connection device, According to the installed fixture structure and the melting degree of the ice assembly (4) to be tested, a weight block is added to the loading area to adjust the center of gravity of the entire falling system so that the center of gravity is stable and located in the middle; and a laser rangefinder is used to determine the initial position of the falling system. Connect the strain sensor, pressure sensor, displacement sensor and external camera system to the computer of the test system and perform zero initialization. After confirming that all equipment is working properly, set the sampling frequency to 5000 Hz, start the data acquisition system, and record the time domain signals of relevant parameters. After recording the test data for at least 1 minute, release the falling system and let it collide with the test board (6). After the falling object collision is completed and the test parameters are stable, the falling object height is changed to conduct multiple tests to obtain multiple sets of parameters. After the test is completed, stop data collection, turn off all instruments, and dismantle the test model.

2. The test method for a drop test smooth release device adapted to a specific tooling structure according to claim 1, characterized in that: The release connecting member (3) is provided with a plurality of mounting holes (301) in the vertical direction, and the mounting holes (301) are tightly connected to the cantilever beam (2).

3. The testing method for a drop test smooth release device adapted to a specific tooling structure according to claim 1, characterized in that: The release connector (3) and the ice body clamp (5) are connected via a release bolt or an electromagnetic device (302).

4. The testing method for a drop test smooth release device adapted to a specific tooling structure according to claim 3, characterized in that: The ice body clamp (5) comprises a limiting plate (501), and a plurality of fixing holes (502) are formed on the limiting plate (501); A first rib plate (503) is vertically provided above the limiting plate (501), and a second rib plate (504) is located on the top of the first rib plate (503) and is parallel to the limiting plate (501). A mounting plate (505) coplanar with the release connector (3) is formed on the side of the second rib plate (504) facing away from the first rib plate (503). The release bolt or electromagnetic device (302) is located between the release connector (3) and the mounting plate (505).

5. The testing method for a drop test smooth release device adapted to a specific tooling structure according to claim 4, characterized in that: A positioning plate (303) is vertically provided at the bottom end of the release connector (3); when the mounting plate (505) is connected to the release connector (3), the positioning plate (303) is in contact with the second rib plate (504).

6. The testing method for a drop test smooth release device adapted to a specific tooling structure according to claim 4, characterized in that: The loading area is the entire surface of the limiting plate (501).

7. The test method according to claim 1, wherein The ice block body of the ice block assembly (4) to be tested is a whole frozen ice block, a connecting piece is frozen in the ice block body, and the connecting piece passes through the fixing hole (502) on the limiting plate (501) to achieve connection.

8. The test method according to claim 1, wherein When the falling system is in its initial state, both the initial velocity and the deflection angle are 0.

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