A test system for distribution state of ice load space on underwater vehicle floating

Abstract

The present application relates to a kind of underwater submersible floating ice load space distribution state test system, belong to ice water pool model test technical field.It includes vertical limb, horizontal limb, rigid base and force sensor, the lower end of the vertical limb is bolted to one end of horizontal limb, the other end of horizontal limb is connected with the lower side of rigid base middle part, rigid base is connected with model through force sensor on it.The present application is applicable to the ice water pool jacking experimental test of each type simulation underwater submersible floating ice process, ensures the constraint stiffness of each model section, and can realize the synchronous measurement of underwater submersible structure floating ice total load and load distribution;Different ice water pool environment is adaptively designed, to ensure that sensor array can be dynamically measured in low temperature underwater for a long time, also avoid the increase of cost caused by selecting standard too high.

Description

Technical Field

[0001] This invention relates to a testing system, belonging to the technical field of ice-water pool model testing. Background Technology

[0002] As global warming accelerates, polar ocean ice sheets are melting, leading to increased scientific research, commercial activities, and development in polar regions. Underwater vehicles (UVs) operating in polar waters may face icebreaking operations. Unlike conventional icebreaking by polar vessels, the icebreaking process for UVs involves the fracture and failure of the ice sheet under vertical loads. In this process, the spatial distribution of the ice load on the UV is crucial for structural strength and maneuverability design. However, the icebreaking process involves complex multi-physics coupling processes and is closely related to the intricate physical and mechanical properties of sea ice materials, resulting in a lack of in-depth and effective research and testing methods from both domestic and international academic and engineering communities.

[0003] Nevertheless, some scholars both domestically and internationally have made some beneficial attempts to address the ice load problem during the surfacing and icebreaking process of underwater submersibles. With the widespread application of methods such as the finite element method, discrete element method, smoothed particle method, and peri-field dynamics in the field of ice mechanics, some scholars at home and abroad have conducted exploratory research on this problem using numerical simulation methods. Among them, Ye et al. (2018) used an aerodynamic mathematical model to simulate the surfacing and icebreaking process of an underwater submersible and analyzed the temporal variation of the ice load on the structure. Wang et al. (2021) used LS-DYNA software to simulate the vertical icebreaking and water emergence process of an underwater submersible and considered the nonlinear interaction between the structure, ice, and water in the simulation. Yue et al. (2021), when simulating the surfacing and icebreaking process of a structure, first determined the main control parameters affecting the dynamic ice load of the structure through dimensional analysis, and then set different initial velocities to study the dynamic characteristics of the ice load during the surfacing and icebreaking process. Ye et al. (2018) used a near-field dynamics method to simulate the contact process between the underwater submersible structure and ice, as well as the ice sheet failure. In the simulation, the structure was treated as a rigid body, and a contact detection algorithm was used to identify the contact position between the structure and the ice, thereby tracking the icebreaking state and the distribution of ice load on the structure at each moment. Liu et al. (2015) simplified the surfacing and icebreaking process of the underwater submersible into a process of the structure being impacted by multiple objects, simulating the mutual interference and coupling process between multiple impact forces.

[0004] In addition to the numerical simulation studies mentioned above, some scholars at home and abroad have also conducted model tests on the collision of ice with typical local structures. Lee et al. (2014) arranged a series of strain measurement points on the inner side of a typical ship hull outer plate to test the deformation of the local outer plate structure under the action of the loading mechanism. Gagnon (2004) prepared multiple model ice blocks to simulate floating ice blocks, and placed these floating ice blocks into a water tank in sequence to collide with the ship model, and tested the contact pressure time history of the ship model surface. Choi et al. (2012) simulated the process of a steel plate structure colliding with ice blocks in the laboratory. In the experiment, the tilt angle and impact speed of the steel plate structure were controllable, so as to test the impact force and ice block damage under different tilt angles and speeds. Kim et al. (2014) fixed the plate frame structure, released ice blocks at a certain height above the plate frame structure, and allowed the ice blocks to fall freely and collide with the plate frame structure. They tested the deformation and fracture of the ice blocks and the deformation of the structure during the collision process, and described the spatial distribution of ice load on the structure.

[0005] In summary, research on the spatial distribution of ice loads during the surfacing and icebreaking process of underwater submersibles mainly includes numerical simulation studies and local structural model experiments. Numerical simulation studies, based on the finite element method, discrete element method, smoothed particle method, and near-field dynamics, simulate the process of an underwater submersible model surfacing and contacting an ice sheet model until its failure, calculating the ice loads acting on the surface of the structural model during this process. However, due to the complexity of ice materials, it is not yet possible to construct a constitutive relationship that accurately describes the deformation and failure process of the ice sheet, meaning that the ice load distribution results obtained through numerical simulation still need to be verified by physical model experiments or field tests. On the other hand, limited physical model experiments mostly target typical local structural models, simulating the collision process between the local structure and the ice, thereby observing the ice failure process and the stress conditions of the local structure. Due to the characteristics of structural experiments and limitations of laboratory conditions, at a large geometric scale, only typical local structures can be tested, and the surfacing and icebreaking process of a complete underwater submersible model cannot be simulated. During the process of an underwater submersible surfacing and breaking ice, there are obviously correlations between the various structural parts, which means that the ice load and structural response results measured when focusing only on local structures will inevitably deviate from the surfacing and ice-breaking process of the complete structure.

[0006] Therefore, existing testing systems for the spatial distribution of loads during the surfacing and ice-breaking process of underwater submersibles mainly have the following problems:

[0007] 1. No adaptive design was made for the ice-water pool test environment. The process of an underwater submersible surfacing and breaking ice is a complex physical process involving the coupling of structure, ice, and water. Only by simulating the submersible's surfacing and breaking ice in an ice-water pool environment can the real-world scenario be reproduced. There is currently no test system suitable for this special test environment, nor is there a targeted design solution.

[0008] 2. There is currently no design scheme for simultaneously measuring the total icebreaking load and load distribution of underwater submersibles. Existing model test systems measure the icebreaking load distribution for large-scale local models or the total icebreaking load for small-scale overall models. Clearly, the total icebreaking load measured for the overall model cannot reflect the load distribution; moreover, icebreaking during surfacing is a continuous process, and the icebreaking processes of different parts of the submersible structure influence each other. The icebreaking load measured in isolation from a local model will differ from the actual icebreaking process of the entire structure. Therefore, there is currently no test system capable of simultaneously measuring both the total icebreaking load and load distribution for the entire underwater submersible model.

[0009] Therefore, there is an urgent need to develop a testing system for the spatial distribution of ice-breaking loads on underwater submersibles to solve the aforementioned technical problems. Summary of the Invention

[0010] To address the aforementioned problems, a testing system for the spatial distribution of ice-breaking loads on an underwater submersible is provided. A brief overview of the invention is given below to provide a basic understanding of certain aspects of the invention. It should be understood that this overview is not an exhaustive summary of the invention. It is not intended to identify key or essential parts of the invention, nor is it intended to limit the scope of the invention.

[0011] The technical solution of the present invention:

[0012] A test system for the spatial distribution of ice-breaking loads on an underwater submersible includes a vertical limb, a horizontal limb, a rigid base, and a force sensor. The lower end of the vertical limb is bolted to one end of the horizontal limb, and the other end of the horizontal limb is connected to the lower middle part of the rigid base. The force sensor is connected to the model on the rigid base.

[0013] Preferably, it also includes a connecting plate, which is fixedly connected to the upper side of the upright and is used to be bolted to the moving base of the lifting device.

[0014] Preferably, the vertical angle β between the upright limb and the horizontal limb is 90°.

[0015] Preferably, the angle α between the model and the horizontal plane of the horizontal limb is 20°-70°.

[0016] Preferably, the length of the horizontal limb is greater than or equal to 1 feature length.

[0017] Preferred: The model comprises several sequentially arranged model segments with gaps between adjacent model segments, and each model segment is connected to a rigid base through several force sensors.

[0018] Preferred configuration: In the model length direction, when the model segment length is less than or equal to 3 times the force sensor length, one force sensor is placed in the middle of the model segment; when the model segment length is greater than 3 times but less than or equal to 6 times the force sensor length, one force sensor can be placed at the front and back of the model segment at a distance of 1 times the force sensor length from the edge; when the model segment length is greater than 6 times the force sensor length, the model segment is further subdivided into segments of less than 3 times the length or between 3 and 6 times the length.

[0019] Along the width of the model, when the bottom contact width of the model is less than or equal to 4 times the width of the force sensor, one sensor can be placed in the width direction of the model; when the bottom contact width of the model is greater than 4 times the width of the force sensor but less than or equal to 8 times, one force sensor can be placed on each side of the model segment at a distance of 1.5 times the width from the contact edge.

[0020] Preferred method: When selecting the force sensor range, it is necessary to estimate the ice-breaking load for each model segment. A semi-theoretical, semi-empirical estimation method for the vertical destructive force of the ice layer under the surface contact ice-breaking mode can be used.

[0021]

[0022] In the formula, P f σ represents the vertical failure load of the ice layer when a circumferential crack penetrates; N Where is the bending strength of the ice layer; h is the ice layer thickness; k is a dimensionless constant; R is the ice layer failure radius; and L is the characteristic length of the ice layer, which can be calculated using the following formula:

[0023]

[0024] In the formula, E is the elastic modulus of ice; υ is the Poisson's ratio of ice; ρ w This is the density of water.

[0025] Preferably, the horizontal limb is provided with a through hole to reduce resistance.

[0026] The present invention has the following beneficial effects:

[0027] 1. This invention is applicable to ice-water pool lifting test of various types of simulated underwater submersibles surfacing and breaking ice. The force sensor array arrangement is designed according to the segmented model of the underwater submersible, which ensures the constraint stiffness of each segment of the model and enables synchronous measurement of the total load and load distribution of the underwater submersible structure (model) during surfacing and breaking ice.

[0028] 2. This invention has made targeted adaptive designs for different ice water pool environments. The sensor range is designed based on the extreme value estimation results of the ice-breaking load of each model segment. It also provides a reference standard for selecting force sensor models that are resistant to low temperature, anti-interference, and waterproof. This avoids inaccurate test results and damage caused by selecting too small a model, ensures that the sensor array can perform dynamic measurements in low temperature water for a long time, and also avoids increased costs caused by selecting too high a standard. Attached Figure Description

[0029] Figure 1 This is a three-dimensional diagram of a test system for the spatial distribution of ice-breaking loads on an underwater submersible.

[0030] Figure 2 This is a side view of a test system for measuring the spatial distribution of ice-breaking loads on an underwater submersible during surfacing.

[0031] Figure 3 This is a top view of a test system for measuring the spatial distribution of ice-breaking loads on an underwater submersible during surfacing.

[0032] In the diagram, 1-connecting plate, 2-vertical limb, 3-horizontal limb, 4-rigid base, 5-force sensor, 6-model, 7-hinged seat, 8-pad, 12-auxiliary frame. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0034] Specific implementation method one: Combining Figure 1-3 This embodiment describes a test system for the spatial distribution of ice-breaking loads on an underwater submersible. The system includes a vertical limb 2, a horizontal limb 3, a rigid base 4, and a force sensor 5. The lower end of the vertical limb 2 is bolted to one end of the horizontal limb 3, and the other end of the horizontal limb 3 is connected to the lower middle part of the rigid base 4. The force sensor 5 is connected to a model 6 on the rigid base 4. This invention incorporates targeted adaptive designs for various ice-water pool environments, making it suitable for different ice-water pool test environments. The force sensor 5 and its signal line for connecting to the data acquisition system are selected based on waterproof performance, anti-interference performance, and low-temperature performance. The data acquisition system includes functions such as sampling frequency settings.

[0035] It also includes a connecting plate 1, which is fixedly connected to the upper side of the upright limb 2. The connecting plate 1 is used to connect with the moving base of the lifting device by bolts. The test system for the spatial distribution state of ice-breaking load of underwater submersible proposed in this invention is often used in conjunction with an ice-water pool simulation test device that can simulate the ice-breaking process of underwater submersible. It is installed on such a lifting device to realize the measurement of ice load on the target submersible structure. For example, the upper end of the support frame of the lifting device is connected to a motor. The support frame has a vertical slide rail. A moving base is slidably arranged in the slide rail of the support frame. A vertical threaded through hole is machined on the moving base. The transmission screw arranged along the slide rail passes through the screw of the moving base. The perforated hole is threadedly connected to the motion base, and the upper end of the transmission screw is connected to the output end of the servo motor through a gearbox. The gearbox can be fixed on the upper end of the support frame. This invention has a greater lifting capacity, can support larger-sized structural models, and meet the needs of larger scale model tests, thereby more realistically simulating the icebreaking process and mechanical behavior of underwater vehicles. This invention is applicable to ice-water pool lifting devices for simulating the surfacing and icebreaking process of various types of underwater vehicles. The force sensor array arrangement is designed according to the segmented model of the underwater vehicle and the type of lifting device, ensuring the constraint stiffness of each model segment and enabling synchronous measurement of the total load and load distribution of the underwater vehicle structure during surfacing and icebreaking.

[0036] The vertical angle β between the upright limb 2 and the horizontal limb 3 is 90°, mainly used to extend the submersible structural model a certain distance under the ice, avoiding damage to the ice sheet by the lifting device during the test, while ensuring that the submersible model has sufficient circumferential and vertical buoyancy space; it also includes an auxiliary frame 12, which is bolted to the other side of the horizontal limb 3, and the auxiliary frame 12 is connected to the attitude adjustment module; the auxiliary frame 12 includes two triangular frames, which are set on both sides of the horizontal limb 3 and the plane formed by the triangular frames is parallel to the horizontal plane, and both the upright limb 2 and the horizontal limb 3 are straight steel frames; the invention has the integrity of crack propagation, and through the design of the support module, it ensures that the distance between the model and the ice sheet is reasonable, so that the model will not affect the integrity of the ice sheet during the ice breaking process, and can realistically capture the formation and propagation behavior of ice breaking cracks; it also includes a hinge seat 7 and two pads 8, and the horizontal limb 3 is connected to the force measuring model through the hinge seat 7. The block rotation connection means that the other end of the horizontal limb 3 is fixedly connected to the rotating shaft of the hinge seat 7, and the rigid base 4 is fixedly connected to the bearing seat of the hinge seat 7. The rotating shaft and the inner ring of the bearing seat are interference fit to achieve rotational connection. The horizontal limb 3 is fixedly connected to the rigid base 4 through two pads 8. The present invention has multi-scenario test adaptability. The model tilt angle can be flexibly controlled by the hinge seat and fixed pads to constrain the structural model at different tilt angles to adapt to the needs of various test scenarios. The force sensor 5 is used to record the load on the model during the floating and ice-breaking process in real time. The force sensor 5 is set on the upper part of the rigid base 4, and the bearing seat of the hinge seat 7 and the pads 8 are bolted to the lower part of the rigid base 4. The two pads 8 are located on both sides of the hinge seat 7. The pads 8 are bolted to the auxiliary frame 12. Several bolt holes can be set on the lower part of the rigid base 4. The auxiliary frame 12 can be connected to the bolt holes at different positions as needed to adjust the lever arm.

[0037] The horizontal angle α between model 6 and horizontal limb 3 is 20°-70°. In order to ensure that the two ends of the model are as far away from the wall of the ice water pool as possible and to avoid the influence of boundary effects, it can be adjusted according to the actual ice water pool environment. The rigid base 4 is a steel structure beam.

[0038] The length of horizontal limb 3 is greater than or equal to 1 characteristic length; the radial crack length can be measured by the characteristic length shown in formula (2). When the distance between the model boundary and the free edge of the ice sheet exceeds 1 characteristic length, the influence of the boundary effect can be ignored; it meets the lifting force requirements, speed range and accuracy requirements, lifting stroke requirements, and structural strength and stiffness requirements in the surfacing and icebreaking test, and the boundary effect of the model ice sheet (free end edge and pool wall boundary) will not interfere with the surfacing and icebreaking process of the submersible model;

[0039] Model 6 is a segmented model, consisting of several sequentially arranged model segments with gaps between adjacent segments. Each model segment is connected to a rigid base 4 via several force sensors 5. This invention possesses efficient data acquisition capabilities, and the equipped high-precision force sensors can record and analyze ice load conditions during the icebreaking process in real time. It supports segmented or integral models, and through flexible sensor configuration, it can accurately measure the total load or load distribution during the icebreaking process, providing reliable data for structural mechanics research. This invention can simultaneously measure the total load and load distribution of a complete underwater submersible model during icebreaking. Under the premise of realistically reproducing the icebreaking process of a complete underwater submersible, it constructs a synchronous measurement system for the total icebreaking load and load spatial distribution, which is applicable to various underwater submersible structures.

[0040] Along the length of model 6, when the length of a model segment is less than or equal to three times the length of force sensor 5, one force sensor 5 is placed in the middle of the model segment; when the length of a model segment is greater than three times the length of the force sensor but less than or equal to six times, one force sensor can be placed at the front and back of the model segment at a distance of one force sensor 5 length from the edge; when the length of a model segment is greater than six times the length of the force sensor, the model segment is further subdivided into segments of less than three times the length or between three and six times the length.

[0041] Along the width of model 6, when the bottom contact width of model 6 is less than or equal to 4 times the width of force sensor 5, one sensor can be arranged in the width direction of model 6; when the bottom contact width of model 6 is greater than 4 times the width of force sensor 5 but less than or equal to 8 times, one force sensor 5 can be arranged on each side of model segment at a distance of 1.5 times the width from the contact edge. The arrangement of force sensors 5 in the two directions forms a sensor array.

[0042] When selecting the force sensor range, it is necessary to estimate the ice-breaking load for each model segment. A semi-theoretical and semi-empirical estimation method for the vertical destructive force of the ice layer under the surface contact ice-breaking mode can be used:

[0043]

[0044] In the formula, P f σ represents the vertical failure load of the ice layer when a circumferential crack penetrates; N Where is the bending strength of the ice layer; h is the ice layer thickness; k is a dimensionless constant; R is the ice layer failure radius; and L is the characteristic length of the ice layer, which can be calculated using the following formula:

[0045]

[0046] In the formula, E is the elastic modulus of ice; υ is the Poisson's ratio of ice; ρ w The density of water;

[0047] The force sensor (5) has a range of 500 kgf, a sensor accuracy of 0.05% FS, a dustproof and waterproof rating of IP68, and a working temperature range of -20℃ to 80℃. This invention has made targeted adaptive designs for different ice water pool environments. The sensor range is designed based on the extreme value estimation results of the floating ice-breaking load of each model segment, and a force sensor model that is resistant to low temperature, anti-interference and waterproof is selected to ensure that the sensor array can perform dynamic measurements in low temperature water for a long time.

[0048] The horizontal limb 3 is provided with a through hole 31 to reduce resistance.

[0049] Example 1:

[0050] Taking a test system for the spatial distribution of ice-breaking load during the surfacing of an underwater submersible and a type of underwater submersible lifting device in an ice-water pool as examples, the connection and installation of the test system are described in detail below:

[0051] (1) Lifting device:

[0052] A type of lifting device suitable for simulating the surfacing and ice-breaking process of an underwater submersible in an ice-water pool serves as the installation foundation for a test system for measuring the spatial distribution of ice-breaking loads during surfacing of an underwater submersible, as proposed in this invention. The test system needs to be designed and modified based on the lifting device and the underwater submersible model, and installed on the lifting device to achieve effective measurement of the spatial distribution of ice-breaking loads on the structure. The lifting device generally includes a lifting mechanism, a cantilever mechanism, and a rigid base, which can effectively control the surfacing speed and surfacing angle of the underwater submersible model. The lifting mechanism is typically installed on a test trailer that spans the width of the ice-water pool and can move along the length of the pool. A servo system drives and controls the vertical movement of the lifting mechanism to ensure that the lifting device possesses… Sufficient lifting force, motion control precision, and stroke range are required. The suspension device generally consists of vertical and horizontal components. The vertical components are used to submerge the underwater vehicle model to a certain depth underwater, ensuring that the structural model has sufficient space for surfacing. The horizontal components are used to extend the underwater vehicle model forward a certain distance under the ice, thereby avoiding interference from the ice sheet edge on the surfacing and icebreaking process. The rigid base is the main component supporting the underwater vehicle model. Its main dimensions must meet the installation requirements of the structural model and have sufficient rigidity to prevent deformation and vibration during vertical movement. At the same time, the rigid base should have the function of adjusting the tilt angle to simulate the surfacing and icebreaking scenarios of the underwater vehicle at different tilt angles.

[0053] (2) Segmented model:

[0054] Currently, the length of commonly used underwater vehicle structures (Model 6) is greater than their width and height, a characteristic that is even more pronounced in large underwater vehicle structures. Based on these structural characteristics, in order to effectively measure the spatial distribution of ice loads on the underwater vehicle model, the structural model can be designed as a segmented structure along its length. The specific principles and methods for segmentation are as follows:

[0055] ① The first point where the underwater submersible touches the ice upon surfacing is the initial concentrated area of ​​ice load. The area completely encompassing this ice-touching area should be divided into segments. In addition, the positions of these segments should be determined with reference to the structural alignment along its length to ensure the continuity of the alignment between segments.

[0056] ② The protruding part of the underwater vehicle's structural lines should be divided into sections to reflect the correspondence between the structural line characteristics and the ice load distribution;

[0057] ③ Based on the above two principles, the remaining undivided parts of the underwater vehicle shall be divided according to the principle of making the segment lengths as uniform as possible;

[0058] ④ In order to avoid the mutual influence of ice loads between different sections and to maintain the complete shape of the underwater submersible structure, appropriate gaps should be left between each section so as not to change the structural line and to prevent the sections from contacting each other during the process of surfacing and breaking ice.

[0059] (3) Arrangement of force sensors:

[0060] In the testing system of this invention, the force sensor array is arranged between the rigid base and the segmented model, and is fixed to the rigid base and the model segments respectively by bolts, serving to connect the two parts of the components and measure the ice load. The number, position and arrangement of the force sensors need to be determined according to the size and shape of the structural model segments. The specific arrangement principles and methods are as follows:

[0061] ① The principle of force sensor placement is to ensure that each model segment has sufficient connection strength and rigidity to avoid displacement of the model segment during the ice-breaking process due to unstable fixed foundation; 1 to 2 independent force sensors are placed under each model segment, depending on the length of the model segment;

[0062] ② Along the length of the model segment, when the length of the model segment is less than or equal to 3 times the length of the force sensor, one force sensor can be placed in the middle of the model segment; when the length of the model segment is greater than 3 times but less than or equal to 6 times the length of the force sensor, one force sensor can be placed at the front and back of the model segment at a distance of 1 sensor length from the edge; when the length of the model is greater than 6 times the length of the force sensor, the model segment should be further subdivided.

[0063] ③ Along the width of the model segments, since underwater submersibles are mostly cylindrical structures, the bottom width of the structure will be smaller than the overall width. When the bottom contact width of the model is less than or equal to 4 times the width of the force sensor, one sensor can be placed along the width of the model. When the bottom contact width of the model is greater than 4 times but less than or equal to 8 times the width of the force sensor, one force sensor can be placed on each side of the model segment at a distance of 1.5 times the width from the contact edge. According to the aspect ratio of the underwater submersible configuration, it is generally unlikely that the width of the model segment will be greater than 8 times the width of the force sensor. If such a special configuration occurs, it is recommended to divide the model into two half-zones (segments) along the width direction. This invention arranges sensors according to the segments and further improves the segmentation by considering the sensor arrangement, thus establishing a stable testing system. It avoids inaccurate test results and damage caused by selecting too small a sensor, ensures that the sensor array can perform dynamic measurements in low-temperature water for a long time, and also avoids increased costs caused by selecting too high a standard.

[0064] (4) Force sensor selection:

[0065] When selecting the force sensor range, the ice-breaking load for each model segment must first be estimated. A semi-theoretical, semi-empirical estimation method for the vertical destructive force of the ice layer under the surface contact ice-breaking mode, proposed by Kerr, can be used.

[0066]

[0067] In the formula, P f σ represents the vertical failure load of the ice layer when a circumferential crack penetrates; N Where is the bending strength of the ice layer; h is the ice layer thickness; k is a dimensionless constant; R is the ice layer failure radius; and L is the characteristic length of the ice layer, which can be calculated using the following formula:

[0068]

[0069] In the formula, E is the elastic modulus of ice; υ is the Poisson's ratio of ice; ρ w The density of water;

[0070] When estimating the extreme values ​​of the icebreaking loads on the model segments, the mutual influence between the segments can be temporarily ignored. The icebreaking loads can be calculated separately for each model segment based on its structural form, and the range of the sensors can be designed in conjunction with the number of force sensors below the segment. On the other hand, the force sensor array needs to work underwater. The sensors should have good low-temperature resistance, anti-interference and waterproof performance, and have dynamic testing capabilities with a testing frequency of not less than 100Hz.

[0071] In this embodiment, the underwater vehicle model is approximately 4.5m long. Based on the structural shape of the underwater vehicle, it is evenly divided into 10 segments along its length, with each segment being approximately 45cm long. The selected force sensor 5 is 15cm long, so one force sensor 5 is placed at the midpoint of each model segment 6. The underwater vehicle model has a cylindrical configuration with an arc-shaped bottom. The force sensor 5 is 5cm wide, so one force sensor 5 is placed at the midpoint of each model segment 6. In summary, placing one force sensor 5 at the midpoint of each model segment 6 satisfies the connection stiffness requirements of the model segments. At the same time, a 1cm gap is left between each model segment 6 to avoid mutual influence of ice loads between segments.

[0072] The ice-breaking load of the underwater submersible model is estimated using the Kerr formula. The underwater submersible model is approximately 5m long and is divided into 10 segments along its length. The ice thickness of the model to be tested is 10cm, so the ice-breaking load of the largest segment is estimated to be approximately 150kgf. Considering the dynamic amplification of the vertical load during the test, a force sensor 5 with a range of 500kgf, an accuracy of 0.05%FS, a dustproof and waterproof rating of IP68, and an operating temperature range of -20℃ to 80℃ is selected. Thus, the total ice-breaking load and the spatial distribution of the load on the target underwater submersible model are simultaneously measured through the force sensor array.

[0073] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutation and combination. Therefore, the present invention will not describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

[0074] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A testing system for the spatial distribution of ice-breaking loads on an underwater submersible during surfacing, characterized in that: It includes a vertical limb (2), a horizontal limb (3), a rigid base (4) and a force sensor (5). The lower end of the vertical limb (2) is connected to one end of the horizontal limb (3), and the other end of the horizontal limb (3) is connected to the rigid base (4). The rigid base (4) is connected to the model (6) through the force sensor (5). It also includes a connecting plate (1), which is connected to the upper side of the vertical limb (2) and is used to be bolted to the lifting device; The horizontal angle α between model (6) and horizontal limb (3) is 20°-70°; The model (6) contains several sequentially arranged model segments with gaps between adjacent model segments. Each model segment is connected to a rigid base (4) through several force sensors (5).

2. The testing system for the spatial distribution of ice-breaking load on an underwater submersible as described in claim 1, characterized in that: The angle β between the upright limb (2) and the horizontal limb (3) is 90°.

3. The testing system for the spatial distribution of ice-breaking load on an underwater submersible as described in claim 2, characterized in that: The length of the horizontal limb (3) is greater than or equal to 1 time the characteristic length of the ice layer.

4. The testing system for the spatial distribution of ice-breaking load on an underwater submersible as described in claim 3, characterized in that: In the length direction of model (6), when the length of model segment is less than or equal to 3 times the length of force sensor (5), one force sensor (5) is placed in the middle of the model segment; when the length of model segment is greater than 3 times the length of force sensor and less than or equal to 6 times, one force sensor is placed at the front and back of the model segment at a distance of 1 time the length of force sensor (5) from the edge; when the length of model segment is greater than 6 times the length of force sensor, the model segment is further subdivided according to the range of less than 3 times the length or 3 times to 6 times the length. Along the width direction of the model (6), when the bottom contact width of the model (6) is less than or equal to 4 times the width of the force sensor (5), one sensor is arranged in the width direction of the model; when the bottom contact width of the model is greater than 4 times the width of the force sensor (5) and less than or equal to 8 times, one force sensor (5) is arranged on each side of the model segment at a distance of 1.5 times the width from the contact edge.

5. The testing system for the spatial distribution of ice-breaking load on an underwater submersible as described in claim 4, characterized in that: When selecting the force sensor range, it is necessary to estimate the ice-breaking load for each model segment, using a semi-theoretical, semi-empirical estimation method for the vertical destructive force of the ice layer under the surface contact ice-breaking mode: (1) In the formula, P f This represents the vertical failure load on the ice layer when a circumferential crack penetrates it. σ N The bending strength of the ice layer; h This refers to the thickness of the ice layer. k It is a dimensionless constant; R The radius of ice layer destruction. L The characteristic length of the ice layer is calculated using the following formula: (2) In the formula, E The elastic modulus of ice; υ Poisson's ratio for ice; ρ w This is the density of water.

6. The testing system for the spatial distribution of ice-breaking load on an underwater submersible as described in claim 1, characterized in that: The horizontal limb (3) is provided with a through hole (31).

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