A testing device and testing method for ship ice crack navigation ice resistance

Abstract

This invention discloses a testing device and method for testing ice resistance during ship navigation via ice cracks. The testing device includes an ice water tank, a ship model, a force sensor, an ice crack forming component, a clamping component, a traveling component, and a main control unit. The ice crack forming component uses a detachable template mounted on rods. By translating and rotating the rods, the template spacing and tilt angle can be adjusted to form ice cracks of different widths, sidewall tilt angles, and irregular shapes. The clamping component has a rotating shaft, allowing the ship model to deflect or tilt to adapt to the direction of the ice cracks. The force sensor is installed between the clamping base and the supporting column to collect three-dimensional ice resistance data in real time. The testing method includes ice crack forming, demolding, ship model installation and attitude adjustment, navigation testing, and data acquisition steps. This invention achieves precise and controllable simulation of the ice crack environment and adaptive adjustment of the ship model's attitude, filling the technical gap in specialized testing of ice crack navigation resistance, and providing test data that more closely reflects actual working conditions.

Description

Technical Field

[0001] This invention relates to the field of ship navigation performance testing technology, and in particular to a testing device and method for testing ice resistance during ship navigation through ice cracks. Background Technology

[0002] During navigation in the Arctic ice region, ships often navigate through naturally formed ice crevasses. Compared to breaking through continuous, flat ice surfaces, navigating along ice crevasses significantly reduces ship resistance and energy consumption, making it a core navigation condition for ships in ice-covered areas. Therefore, accurately obtaining the ice resistance of ships navigating in ice-covered environments is of great significance for optimizing ship hull lines, matching power systems, and managing navigation safety in ice-covered areas.

[0003] The methods for obtaining ice resistance data for ships in ice-covered areas are mainly divided into actual sea trials and indoor ice-water tank model tests. Indoor ice-water tank tests, with their advantages of controllable environment, adjustable parameters, and low cost, are a commonly used method for studying ship performance in ice-covered areas. Existing ice-water tank testing technologies primarily target icebreaking resistance testing on continuous, smooth ice surfaces and ship navigation resistance testing in broken ice zones. This involves creating a complete ice surface or broken ice condition under experimental conditions, allowing the ship to navigate within it, and thus obtaining ice resistance data. For example, CN105966550B discloses a combined movable sealed model ice-water tank, but it only involves the tank structure and refrigeration system, and can only simulate a complete ice surface. CN107014587A uses polypropylene plates to simulate broken ice zones. However, the actual main operating condition is navigation along ice cracks, and the two test modes mentioned above cannot accurately reflect the ice resistance experienced by ships navigating along ice cracks. Summary of the Invention

[0004] Objective of the Invention: The objective of this invention is to provide a testing device for measuring the ice resistance of ships navigating through ice cracks that can controllably form irregular ice cracks. Furthermore, another objective of this invention is to provide a method for testing the ice resistance of ships navigating through ice cracks.

[0005] Technical Solution: The present invention provides a testing device for ice resistance during ship navigation via ice cracks, comprising an ice water tank, a ship model, and a force sensor for collecting the ice resistance experienced by the ship model. Guide rails are installed above both sides of the opening of the ice water tank. The device also includes an ice crack forming component disposed within the ice water tank for forming ice cracks of different widths and shapes, a clamping component for holding the ship model, a traveling component for moving the clamping component along the guide rails, and a main control unit electrically connected to the traveling component and the force sensor. The clamping component can cause the ship model to deflect or tilt relative to the traveling component to adapt to the direction of the ice cracks.

[0006] Furthermore, the ice crack forming component includes two horizontal rods passing through both sides of the ice water pool and parallel to the guide rail, a groove opened on the wall of the ice water pool, and a template detachably installed on the rods. The two ends of the rods can slide in the groove. By translating and rotating the rods, the spacing and tilt angle of the templates can be adjusted to form ice cracks of different widths and tilt angles.

[0007] Preferably, the rod has multiple threaded holes, and the rod is connected to the template by bolts; the threaded pair is provided with an antifreeze lubrication layer to prevent the threaded pair from freezing and getting stuck in low-temperature environments.

[0008] Preferably, there are at least two templates, and the inner wall of the template is coated with Teflon to minimize the brittle cracking of the ice seam edges caused by removing the template.

[0009] Furthermore, the walking assembly includes a walking frame spanning above the ice water pool, walking wheel sets located below both ends of the walking frame and adapted to the guide rail, a drive motor located on the walking frame, a crossbeam located on the walking frame, and a lateral adjustment groove located on the crossbeam; the clamping assembly can slide within the lateral adjustment groove.

[0010] Furthermore, the clamping assembly includes a transverse slider adapted to the transverse adjustment slide, a support column erected perpendicular to the transverse slider and pointing downwards, a rotating shaft connected to the bottom of the support column, and a clamping seat located at the bottom of the rotating shaft for clamping the ship model; the rotating shaft drives the clamping seat to rotate, so that the ship model adapts to the direction of the ice crack.

[0011] Furthermore, a force sensor is installed between the clamping seat and the support column.

[0012] The present invention also provides a method for testing ice resistance during ship navigation using the above-mentioned testing device, comprising the following steps:

[0013] S1. Install the template of the ice crack forming component onto the rod. Adjust the spacing and tilt angle between the templates to the preset experimental value by translating and rotating the rod. Pour water into the ice water pool and start the refrigeration system to freeze the water on the outside of the template and the template surface to form an ice crack with a preset width and side wall tilt angle.

[0014] S2. After the ice crack sidewall is frozen and formed, the template is detached from the ice surface by loosening the connecting bolts and slightly vibrating or locally heating the template, and then the template is removed from the ice water pool.

[0015] S3. Fix the boat model on the clamping seat of the clamping assembly, adjust the position of the transverse slider on the crossbeam of the traveling frame so that the boat model is aligned with the center line of the ice crevice, and adjust the deflection angle of the boat model relative to the traveling assembly through the rotation axis of the clamping assembly so that the sailing direction of the boat model is adapted to the direction of the ice crevice.

[0016] S4. Set the travel speed of the walking component through the main control unit, start the drive motor, and make the walking component move along the guide track, driving the clamping component and the boat model to travel along the ice crevice.

[0017] S5. During navigation, the force sensor collects the ice resistance experienced by the model boat in real time and transmits the collected data to the main control unit for storage and analysis.

[0018] Furthermore, in step S1, the thickness of the ice crack is adjusted by controlling the cooling time and cooling temperature; salt water of different concentrations is added to the water in the ice water pool to adjust the ice strength of the ice crack.

[0019] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0020] (1) The width and sidewall tilt angle of the ice crack can be flexibly adjusted, and ice cracks of different specifications can be formed in a controllable manner according to experimental needs. The test environment is highly consistent with the actual ship working conditions.

[0021] (2) The rotating shaft in the clamping assembly can deflect or tilt the ship model to adapt to the direction of irregular ice cracks; the horizontal slider can adjust the ship model to align with the center line of the ice crack, so that the ship model's posture can automatically adapt to the direction of the ice crack without human intervention, and the test data is more realistic. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the testing device of the present invention;

[0023] Figure 2 This is a schematic diagram of the walking component.

[0024] Figure 3 This is a schematic diagram of the clamping assembly.

[0025] Figure 4 This is a schematic diagram of the ice seam forming component. Detailed Implementation

[0026] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0027] like Figure 1As shown, the ship ice crack navigation ice resistance testing device of this embodiment includes: an ice water tank 1, a ship model 2, a force sensor 3, an ice crack forming component 4, a clamping component 5, a walking component 6, and a main control unit. The ice water tank 1 is the supporting base of the entire device and is made of polyurethane thermal insulation composite material to maintain the low temperature testing environment inside the tank. A refrigerant exchange pipe is installed inside the tank, connected to an external refrigeration unit. Guide rails 11 are installed above both sides of the opening of the ice water tank 1. The guide rails 11 are T-shaped rails used to guide the movement of the walking component 6. The T-shaped protrusion structure of the rails can limit the movement trajectory of the walking wheel assembly 62 and prevent the walking wheel assembly from derailing. Limiting blocks are provided at the ends of the guide rails 11 to limit the movement stroke of the walking component.

[0028] Walking component 6, etc. Figure 2 As shown, the traveling frame 61 spans above the ice water pool 1, with traveling wheel sets 62 installed at both ends below it, which mate with the guide rails 11. The traveling wheel sets 62 use low-temperature resistant polyurethane wheel surfaces and are filled with low-temperature grease to prevent wheel axle jamming in low-temperature environments. The traveling frame 61 also has a drive motor 63 and a crossbeam 64. The output shaft of the drive motor 63 is connected to a gear, which meshes with a rack fixed to the side wall of the ice water pool, forming a gear and rack transmission pair. The drive motor 63 is mounted on the side of the traveling frame via a servo drive mounting bracket, and a low-temperature insulation protective shell is added to the outside of the motor to prevent motor starting failure in low-temperature environments. The crossbeam 64 is the main load-bearing structure of the traveling frame, made of channel steel profiles, and also provides sliding support for the lateral adjustment slide 65. The lateral adjustment slide 65 is a T-slot, which drives the lateral slider 51 of the clamping assembly to adjust its lateral position, so that the boat model 2 can adapt to the ice crevasse channel.

[0029] like Figure 3As shown, the clamping assembly 5 includes a horizontal slider 51, a support column 52, a rotating shaft 53, and a clamping seat 54. The horizontal slider 51 is slidably fitted with a horizontal adjustment groove 65, allowing it to move laterally along the groove. The support column 52 consists of three 316L stainless steel columns, symmetrically arranged, with their upper ends fixedly connected to the horizontal slider 51 to support the weight of the model boat. The rotating shaft 53 is rotatably connected to the bottom of the support column 52, employing a ball joint or cylindrical joint structure, allowing the model boat 2 to deflect around the vertical axis and tilt around the horizontal axis, enabling rotational adjustment of the model boat to adjust its sailing attitude and adapt to sailing tests with irregular ice cracks. The clamping seat 54 is installed at the bottom of the rotating shaft 53 to fix the model boat 2; the clamping seat is a rectangular plate with multiple pre-drilled screw holes, and corresponding threaded holes or through holes are also made on the model boat 2. Bolts are used to fasten the model boat to the clamping seat. By selecting different combinations of screw holes, different sizes of model boats can be accommodated. Force sensor 3 is installed between the lower end of support column 52 and the upper surface of clamping seat 54, and is a three-dimensional force sensor. The sensor signal line runs upward along support column 52 and connects to the main control unit. The main control unit is electrically connected to drive motor 63 and force sensor 3, and is used to set the sailing speed and receive and store resistance data.

[0030] like Figure 4 As shown, the ice seam forming component 4 includes rods 41, a chute, and a template 43. Rods 41 are two stainless steel round rods that pass horizontally through the ice water pool 1 and are parallel to the guide rail 11. The chute is formed on the side wall of the ice water pool 1. Both ends of the rods extend outside the ice water pool, and rollers are installed at both ends and embedded in the chute, allowing them to slide and rotate within the chute. Threads are machined on the exposed ends of the rods 41 extending from the ice water pool wall, and two locking nuts and anti-loosening washers are provided. Once the position and angle of the rods 41 are determined, the rods are reliably fixed. Multiple threaded holes 44 are provided on the rods 41. The template 43 is connected to the rods 41 by bolts, and antifreeze grease is applied to the threaded joints to prevent freezing at low temperatures. The template 43 is a stainless steel plate with a Teflon coating on its inner wall. In this embodiment, the surface of the template is curved; however, for better practicality, it can also be made with a flat surface as needed. The distance between the two templates 43 can be adjusted by translating the rod 41, and the templates 43 can be tilted at different angles by rotating the rod 41, thus creating ice cracks with different widths and tilt angles. Depending on the experimental requirements, the shape of the templates can also be changed to form ice cracks of different shapes.

[0031] Example 2

[0032] The present invention also discloses a method for testing ice resistance during ship navigation via ice cracks using the testing apparatus of Example 1, comprising the following steps:

[0033] S1. Install template 43 onto rod 41 with bolts. Adjust the spacing and tilt angle between templates to the preset experimental value by translating and rotating the rod. Inject artificial simulated seawater into ice water pool 1 and start the refrigeration system. The water freezes on the outside of template 43 and on the template surface, forming an ice layer and ice cracks with a preset width and side wall tilt angle.

[0034] During the ice-making process, an appropriate amount of salt water is added to the water to adjust the bending strength of the ice to the target value.

[0035] S2. After the sidewall of the ice crevasse has frozen to the preset thickness, stop the cooling. Use a wrench to loosen the bolts connecting the template 43 and the rod 41, tap the rod 41 lightly to separate the template 43 from the ice surface, and then move the rod 41 to pull the template 43 out of the ice water pool and remove it, exposing the ice crevasse channel.

[0036] S3. Place the boat model under the clamping seat 54 and fix it to the pre-embedded nut on the top of the boat model 2 by passing screws through the screw holes of the clamping seat 54; slide the horizontal slider 51 to align the boat model 2 with the center line of the ice crack and lock the slider; rotate the rotating shaft 53 to adjust the deflection angle of the boat model 2 so that the sailing direction of the boat model 2 is adapted to the initial direction of the ice crack.

[0037] S4. Set the travel speed and travel distance of the walking component 6 through the main control unit, start the drive motor 63, the walking wheel set 62 moves along the guide rail 11, and the walking frame 61 drives the clamping component 5 and the boat model 2 to travel at a constant speed along the ice crevice.

[0038] S5. During navigation, force sensor 3 collects the longitudinal resistance, lateral force and vertical force on the model boat 2 in real time, and the data is transmitted to the main control unit through the wireless module.

[0039] Example 3

[0040] This embodiment differs from Embodiment 1 in that it uses multiple sets of templates that can be independently adjusted to simulate irregular ice cracks with gradually changing widths. For example, multiple sets of templates can be set along the length of the ice water pool: the first set has a spacing of 300mm, the second set has a spacing of 280mm, the third set has a spacing of 260mm, and so on, decreasing sequentially. This method can realistically simulate the irregular shape of natural ice cracks.

Claims

1. A testing device for ice resistance during ship navigation via ice cracks, comprising an ice water tank (1), a ship model (2), and a force sensor (3) for collecting the ice resistance experienced by the ship model, wherein guide rails (11) are installed above both sides of the opening of the ice water tank (1), characterized in that, It also includes an ice crack forming component (4) installed in the ice water pool (1) for forming ice cracks of different widths and shapes, a clamping component (5) for clamping the boat model (2), a walking component (6) that drives the clamping component to move along the guide rail (11), and a main control unit electrically connected to the walking component and the force sensor; the clamping component (5) can cause the boat model to deflect or tilt relative to the walking component (6) to adapt to the direction of the ice crack.

2. The testing device for ship ice crack navigation ice resistance according to claim 1, characterized in that, The ice crack forming component (4) includes two horizontal rods (41) that pass through both sides of the ice water pool (1) and are parallel to the guide rail (11), a groove opened on the wall of the ice water pool, and a template (43) that can be detachably installed on the rods (41). The two ends of the rods (41) can slide in the groove. By translating and rotating the rods, the spacing and tilt angle of the templates can be adjusted to form ice cracks of different widths and tilt angles.

3. The testing device for ship ice crack navigation ice resistance according to claim 2, characterized in that, The rod (41) is provided with multiple threaded holes (44), and the rod (41) is connected to the template (43) by bolts; the threaded pair is provided with an antifreeze lubricating layer.

4. The testing device for ship ice crack navigation ice resistance according to claim 2, characterized in that, There are at least two templates (43).

5. The testing apparatus for ship ice crack navigation ice resistance according to claim 2, characterized in that, The inner wall of the template (43) has a Teflon coating.

6. The testing apparatus for ship ice crack navigation ice resistance according to claim 1, characterized in that, The walking assembly (6) includes a walking frame (61) spanning above the ice water pool (1), a set of walking wheels (62) located below both ends of the walking frame and adapted to the guide rail (11), a drive motor (63) on the walking frame (61), a crossbeam (64) passing through the walking frame, and a transverse adjustment groove (65) on the crossbeam (64); the clamping assembly (5) can slide within the transverse adjustment groove.

7. The testing apparatus for ship ice crack navigation ice resistance according to claim 1, characterized in that, The clamping assembly (5) includes a horizontal slider (51) adapted to the horizontal adjustment slide (65), a support column (52) perpendicular to the horizontal slider and downward, a rotating shaft (53) connected to the bottom of the support column (52), and a clamping seat (54) located at the bottom of the rotating shaft and used to clamp the ship model; the rotating shaft drives the clamping seat to rotate, so that the ship model adapts to the direction of the ice crack.

8. The testing apparatus for ship ice crack navigation ice resistance according to claim 7, characterized in that, The force sensor (3) is installed between the clamping seat (54) and the support column (52).

9. A method for testing the ice resistance of a ship navigating ice cracks using the testing apparatus according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Install the template of the ice crack forming component onto the rod. Adjust the spacing and tilt angle between the templates to the preset experimental value by translating and rotating the rod. Pour water into the ice water pool and start the refrigeration system to freeze the water on the outside of the template and the template surface to form an ice crack with a preset width and side wall tilt angle. S2. After the ice crack sidewall is frozen and formed, the template is detached from the ice surface by loosening the connecting bolts and slightly vibrating or locally heating the template, and then the template is removed from the ice water pool. S3. Fix the boat model on the clamping seat of the clamping assembly, adjust the position of the transverse slider on the crossbeam of the traveling frame so that the boat model is aligned with the center line of the ice crevice, and adjust the deflection angle of the boat model relative to the traveling assembly through the rotation axis of the clamping assembly so that the sailing direction of the boat model is adapted to the direction of the ice crevice. S4. Set the travel speed of the walking component through the main control unit, start the drive motor, and make the walking component move along the guide track, driving the clamping component and the boat model to travel along the ice crevice. S5. During navigation, the force sensor collects the ice resistance experienced by the model boat in real time and transmits the collected data to the main control unit for storage and analysis.

10. The test method according to claim 9, characterized in that, In step S1, the thickness of the ice crack is adjusted by controlling the cooling time and cooling temperature; salt water of different concentrations is added to the water in the ice water pool to adjust the ice strength of the ice crack.

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