Numerical calculation method for water outlet icebreaking of navigation body and related equipment

Abstract

The embodiment of the invention discloses a numerical calculation method for water outlet icebreaking of a navigation body and related equipment, and the method comprises the steps: generating a floating ice field geometric model according to a working condition, and constructing a navigation body model of the navigation body; grid division is carried out on the floating ice field geometric model and the navigation body model, and a water outlet icebreaking calculation model is obtained; fluid-solid coupling relation definition is conducted on the effluent icebreaking calculation model, and an optimized effluent icebreaking calculation model is obtained; the optimized water outlet icebreaking calculation model is used for simulating the water outlet icebreaking conditions of the navigation body at different moments, and water outlet icebreaking numerical values of the navigation body at different moments are obtained. The fluid-solid coupling relation definition can more accurately describe the interaction between fluid and solid, and in the water outlet icebreaking process, collision and extrusion between a navigation body and an ice layer and subsequent icebreaking behaviors all relate to a complex fluid-solid coupling phenomenon, so that the fluid-solid coupling relation definition is carried out on the water outlet icebreaking calculation model, and the calculation accuracy is improved. Therefore, an accurate value of water outlet icebreaking of the navigation body is obtained.

Description

[Technical field]

[0001] The present invention relates to the field of marine engineering, and in particular to a numerical calculation method and related equipment for a navigation body to break ice when leaving water. [Background technology]

[0002] As global climate change intensifies, shipping and resource development in polar regions are gradually gaining attention. Polar shipping is not only of great significance to global trade, but also provides new opportunities for scientific research and resource development. In recent years, many countries have paid attention to polar regions, conducted corresponding technical research and investment, developed related polar engineering equipment, and promoted the development of polar marine engineering.

[0003] As an important equipment in marine research, the navigation body can be carried by submarines or large UUVs to the polar regions for release. In the polar environment, it is necessary to overcome the resistance and damage of floating ice to ensure navigation safety and efficiency. The study of the process of emerging from the water and breaking ice has become an important part of the design and performance evaluation of navigation bodies. At present, the research on the interaction between navigation bodies and floating ice during the process of emerging from the water in polar regions is gradually increasing, covering multiple aspects such as experimental analysis and numerical simulation. Although the existing research has made certain progress, most methods rely on experimental data and lack systematic numerical calculation support, resulting in deficiencies in the accuracy and repeatability of the research results. Existing numerical models often fail to effectively consider the complex fluid-solid coupling effects between the navigation body and the floating ice, and do not consider the direct collision between the navigation body and the floating ice, resulting in inaccurate numerical calculations of the navigation body emerging from the water and breaking ice. [Summary of the invention]

[0004] In view of this, the present invention provides a numerical calculation method and related equipment for a navigation body to break ice when out of water.

[0005] The specific technical scheme of the first embodiment of the present invention is: a numerical calculation method for a navigation body breaking ice out of water, the method comprising: presetting the working conditions of the navigation body during navigation; the working conditions include floating ice size, navigation body speed, floating ice field thickness and floating ice field density; generating a floating ice field geometric model according to the working conditions, and constructing a navigation body model of the navigation body; meshing the floating ice field geometric model and the navigation body model to obtain a water-out and ice-breaking calculation model; the water-out and ice-breaking calculation model includes the gridded floating ice field geometric model and the gridded navigation body model; defining the fluid-solid coupling relationship of the water-out and ice-breaking calculation model to obtain an optimized water-out and ice-breaking calculation model; using the optimized water-out and ice-breaking calculation model to simulate the water-out and ice-breaking conditions of the navigation body at different times to obtain the collision load of the navigation body at different times; the collision load is the water-out and ice-breaking value of the navigation body.

[0006] Preferably, the fluid-solid coupling relationship of the water-out-of-water icebreaking calculation model is defined to obtain an optimized water-out-of-water icebreaking calculation model, including: using Lagrangian grid description between the gridded floating ice field geometric model and the gridded navigation body model; using Euler grid description between the water area and the air domain in the water-out-of-water icebreaking calculation model; and using fluid-solid coupling relationship to simulate the fluid-solid coupling effect between the gridded navigation body model, the gridded floating ice field geometric model, the water area and the air domain to obtain the optimized water-out-of-water icebreaking calculation model.

[0007] Preferably, before simulating the water-breakthrough and ice-breaking conditions of the navigation body at different times using the optimized water-breakthrough and ice-breaking calculation model, it also includes: defining the contact relationship in the optimized water-breakthrough and ice-breaking calculation model; wherein, defining the contact relationship includes defining the contact relationship and the erosion contact deformation relationship between the floating ice layer and the water area in the optimized water-breakthrough and ice-breaking calculation model.

[0008] Preferably, before simulating the water-emergence and ice-breaking conditions of the navigation body at different times using the optimized water-emergence and ice-breaking calculation model, it also includes: defining the boundary conditions in the optimized water-emergence and ice-breaking calculation model; wherein, defining the boundary conditions includes adopting non-reflection boundary conditions for the periphery and upper and lower surfaces of the water domain and the air domain, and adopting free boundary conditions for the periphery of the floating ice field geometric model.

[0009] Preferably, the method of using the optimized water-out and ice-breaking calculation model to simulate the water-out and ice-breaking conditions of the navigation body at different times to obtain the collision load of the navigation body at different times includes: using a penalty function algorithm and an ALE algorithm to monitor the relative position between the floating ice layer and the navigation body in the optimized water-out and ice-breaking calculation model at each moment; judging the penetration condition of the relative position between the floating ice layer and the navigation body; if a penetration condition exists, applying a resistance force to the optimized water-out and ice-breaking calculation model to resist and eliminate the penetration condition, and obtaining the collision load based on the resistance force.

[0010] Preferably, obtaining the collision load based on the resistance force includes: obtaining the collision load according to the resistance force, the acceleration and navigation speed of the navigation body at a current moment.

[0011] Preferably, after meshing the ice field geometric model and the navigation body model to obtain the water-out-of-water icebreaking calculation model, the method further includes: obtaining the pressure value and strain value of each ice field unit in the meshed ice field geometric model; wherein the total number of ice fields is the same as the number of meshes; judging whether the pressure value and the strain value of the target ice field unit meet a preset failure standard; the preset failure standard is that the pressure value is less than a preset pressure standard value or the strain value is greater than a preset strain standard value; the target ice field unit is any one of all the ice fields; if the preset failure standard value is met, deleting the target ice field unit in the meshed ice field geometric model to obtain a valid ice field geometric model; and using the valid ice field geometric model as the meshed ice field geometric model to perform the steps of defining the fluid-solid coupling relationship of the water-out-of-water icebreaking calculation model to obtain an optimized water-out-of-water icebreaking calculation model.

[0012] The specific technical scheme of the second embodiment of the present invention is: a numerical calculation system for a navigation body to break ice when leaving the water, the system comprising: a working condition acquisition module, a model construction model, a meshing module, a fluid-solid coupling relationship definition module and a simulation module; the working condition acquisition module is used to preset the working condition of the navigation body during navigation; the working condition includes the size of floating ice, the speed of the navigation body, the thickness of the floating ice field and the density of the floating ice field; the model construction model is used to generate a floating ice field geometric model according to the working condition, and construct the navigation body model of the navigation body; the meshing module is used to calculate the floating ice field geometric model and the floating ice field density; the model construction model ... The navigation body model is gridded to obtain a water-emerging and ice-breaking calculation model; the water-emerging and ice-breaking calculation model includes a gridded floating ice field geometry model and a gridded navigation body model; the fluid-solid coupling relationship definition module is used to define the fluid-solid coupling relationship of the water-emerging and ice-breaking calculation model to obtain an optimized water-emerging and ice-breaking calculation model; the simulation module is used to use the optimized water-emerging and ice-breaking calculation model to simulate the water-emerging and ice-breaking conditions of the navigation body at different times to obtain the collision load of the navigation body at different times; the collision load is the water-emerging and ice-breaking value of the navigation body.

[0013] The specific technical solution of the third embodiment of the present invention is: a numerical calculation device for a navigation body to break ice out of water, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method as described in any one of the first embodiments of the present application.

[0014] The specific technical solution of the fourth embodiment of the present invention is: a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to perform the steps of the method described in any one of the first embodiments of the present application.

[0015] Implementing the embodiments of the present invention will have the following beneficial effects:

[0016] The present invention simulates the actual situation of the vehicle during navigation by presetting the working conditions of the vehicle during navigation; generates a geometric model of the ice floe field according to the working conditions, and constructs a vehicle model of the vehicle; performs mesh division on the geometric model of the ice floe field and the vehicle model to obtain a water-breaking ice-breaking calculation model; defines the fluid-structure interaction relationship for the water-breaking ice-breaking calculation model to obtain an optimized water-breaking ice-breaking calculation model; uses the optimized water-breaking ice-breaking calculation model to simulate the water-breaking ice-breaking situation of the vehicle at different times to obtain the water-breaking ice-breaking numerical values of the vehicle at different times. Defining the fluid-structure interaction relationship can more accurately describe the interaction between the fluid and the solid, and during the water-breaking ice-breaking process, the collision, extrusion and subsequent ice-breaking behavior between the vehicle and the ice layer all involve complex fluid-structure interaction phenomena. Therefore, by defining the fluid-structure interaction relationship for the water-breaking ice-breaking calculation model, accurate numerical values of the vehicle's water-breaking ice-breaking can be obtained.

Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a flowchart of the steps of the numerical calculation method for the vehicle's water-breaking ice-breaking;

[0019] Figure 2 It is a mesh division diagram;

[0020] Figure 3 It is a schematic diagram of the ALE algorithm principle;

[0021] Figure 4 It is a calculation result diagram of ice layer fragmentation;

[0022] Figure 5 It is a cloud diagram of ice floe pressure at different times;

[0023] Figure 6 It is a calculation result diagram of the water load during the vehicle's ice-breaking and water-emerging process;

[0024] Figure 7 It is a schematic structural diagram of the numerical calculation system for the vehicle's water-breaking ice-breaking;

[0025] Figure 8 It is an internal structure diagram of a computer device;

[0026] Among them, 201 is the working condition acquisition module; 202 is the model construction model; 203 is the mesh generation module; 204 is the fluid-structure interaction relationship definition module; 205 is the simulation module.

Specific Embodiments

[0027] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0028] The terms "first", "second", etc. in the specification and claims of the present application and the accompanying drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or modules is not limited to the listed steps or modules, but may optionally further include steps or modules that are not listed, or may optionally further include other steps or modules inherent to these processes, methods, products, or devices.

[0029] Referring to "embodiment" herein means that a specific feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The phrase appears in various positions in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

[0030] Please refer to Figure 1 , which is a step flowchart of a numerical calculation method for a vehicle body to break ice when leaving the water in the first embodiment of the present application, and can obtain accurate numerical values for the vehicle body to break ice when leaving the water. The method includes:

[0031] Step 101, preset the working conditions of the vehicle body during navigation; the working conditions include the size of floating ice, the speed of the vehicle body, the thickness of the floating ice field, and the density of the floating ice field;

[0032] Step 102, generate a geometric model of the floating ice field according to the working conditions, and construct a vehicle body model of the vehicle body;

[0033] Step 103, perform mesh generation on the geometric model of the floating ice field and the vehicle body model to obtain a calculation model for breaking ice when leaving the water; the calculation model for breaking ice when leaving the water includes the geometric model of the floating ice field after mesh generation and the vehicle body model after mesh generation;

[0034] Step 104: Define the fluid-structure coupling relationship for the water-emergence ice-breaking calculation model to obtain an optimized water-emergence ice-breaking calculation model;

[0035] Step 105: Use the optimized water-emergence ice-breaking calculation model to simulate the water-emergence ice-breaking conditions of the vehicle at different times to obtain the collision loads of the vehicle at different times; the collision loads are the water-emergence ice-breaking numerical values of the vehicle.

[0036] Specifically, the working conditions can also include operations related to the navigation situation such as speed, attitude, and position, etc. Based on the VORNONI theory and combined with the working conditions, a series of random polygons are generated to establish a geometric model of the floating ice field. Specifically:

[0037] Randomly generate a series of points within the required area. These points will be used as the generation points of the Voronoi polygons, and the number and distribution of the points can be adjusted according to the scale and complexity of the floating ice field. Use the Voronoi algorithm (such as the Voronoi function in scipy.spatial) to calculate the Voronoi diagram based on the generated point set. The Voronoi diagram divides the area into multiple polygons, and each polygon contains a generation point, and the distance from this point to all points on the polygon boundary is less than the distance to other generation points. According to the actual situation of the floating ice field, adjust the shape of the generated Voronoi polygons. This can be achieved by adjusting the position and number of the generation points or applying additional geometric transformations. According to the movement and deformation of the floating ice under the vehicle's working conditions, further adjust the polygons. For example, the drift and rotation of the floating ice under the action of the water flow, as well as the possible fragmentation and recombination processes, can be simulated. To simulate the randomness of the floating ice field, random factors can be introduced during the generation and adjustment of the polygons. For example, random perturbations can be added when generating the points, or random transformations can be applied when adjusting the polygon shape. Integrate the adjusted Voronoi polygons together to form a complete geometric model of the floating ice field. Ensure seamless connection between the polygons, and there are no overlapping or missing areas. Define properties for each polygon in the floating ice field, such as thickness, density, strength, etc., and these properties can be set according to the actual situation of the floating ice and the vehicle's working conditions. Apply the established geometric model of the floating ice field to the working condition analysis of the vehicle. By simulating the interaction between the vehicle and the floating ice, evaluate the performance and safety of the vehicle.

[0038] Perform mesh division on the geometric model of the floating ice field and the vehicle model to obtain a water-emergence ice-breaking calculation model; all models use hexahedral mesh division, and the mesh in the collision area is appropriately refined; the mesh sizes of the water area and the air area are kept consistent, and co-node processing is performed on the meshes of the water area and the air area; after the mesh division, check the mesh quality, and the mesh division situation is as Figure 2 shown.

[0039] The method in this embodiment simulates the actual situation of the vehicle during navigation by presetting the working conditions of the vehicle during navigation; generates a floating ice field geometric model according to the working conditions, and constructs a vehicle model of the vehicle; divides the grids of the floating ice field geometric model and the vehicle model to obtain a water-emerging ice-breaking calculation model; defines the fluid-structure interaction relationship for the water-emerging ice-breaking calculation model to obtain an optimized water-emerging ice-breaking calculation model; uses the optimized water-emerging ice-breaking calculation model to simulate the water-emerging ice-breaking conditions of the vehicle at different times, and obtains the water-emerging ice-breaking numerical values of the vehicle at different times. Defining the fluid-structure interaction relationship can more accurately describe the interaction between the fluid and the solid, and during the water-emerging ice-breaking process, the collision, extrusion and subsequent ice-breaking behavior between the vehicle and the ice layer all involve complex fluid-structure interaction phenomena. Therefore, by defining the fluid-structure interaction relationship for the water-emerging ice-breaking calculation model, the accurate water-emerging ice-breaking numerical values of the vehicle can be obtained. Define the fluid-structure interaction relationship for the water-emerging ice-breaking calculation model to obtain an optimized water-emerging ice-breaking calculation model. Use the optimized water-emerging ice-breaking calculation model to simulate the water-emerging ice-breaking conditions of the vehicle at different times, and obtain the collision load of the vehicle at different times; the collision load is the water-emerging ice-breaking numerical value of the vehicle.

[0040] In a specific embodiment, the defining the fluid-structure interaction relationship for the water-emerging ice-breaking calculation model to obtain an optimized water-emerging ice-breaking calculation model includes: using Lagrangian grids to describe between the grid-divided floating ice field geometric model and the grid-divided vehicle model; using Euler grids to describe between the water area and the air area in the water-emerging ice-breaking calculation model; using the fluid-structure interaction relationship to simulate the fluid-structure interaction effect between the grid-divided vehicle model, the grid-divided floating ice field geometric model, the water area and the air area, and obtaining the optimized water-emerging ice-breaking calculation model.

[0041] Specifically, first define the fluid-structure interaction relationship. The two solid regions of the vehicle and the ice layer are described by Lagrangian grids, and the two fluid regions of the water area and the air area are described by Euler grids. Define the fluid-structure interaction relationship through CONSTRAINED_LAGRANGE_IN_SOLID to simulate the fluid-structure interaction effect between the vehicle, the ice layer, the water and the air. The ALE method allows the grid to be independent of the object motion in time, enabling the grid to be re-divided as needed, and can simultaneously handle the dynamic behaviors of the fluid and the solid, maintaining numerical stability. The ALE principle is as Figure 3 shown, and its control equation is:

[0042]

[0043] where ρ is the fluid density, V is the velocity field, σ is the stress tensor, f is the body force, e is the energy per unit volume, k is the thermal conductivity, T is the temperature, and Q is the source term.

[0044] In a specific embodiment, before simulating the ice-breaking situation of the vehicle when emerging from the water at different times using the optimized ice-breaking calculation model for emerging from the water, the following steps are further included: defining the contact relationship in the optimized ice-breaking calculation model for emerging from the water; wherein, defining the contact relationship includes defining the contact relationship and the erosion contact deformation relationship between the floating ice layer and the water area in the optimized ice-breaking calculation model for emerging from the water.

[0045] Specifically, the contact between ice layers themselves is defined using CONTACT_SAINGLE_SURFACE, and the contact between ice and water is defined using the keyword CONTACT_ERODING_SURFACE_TO_SURFACE, considering the erosion effect between the two. The theoretical formula for erosion contact is as follows:

[0046] The calculation formula for the contact pressure p is: where F n is the normal contact force, A is the contact area, and F n is a physical quantity related to the contact stiffness. The physical quantity related to the contact stiffness, and the contact stiffness is an important parameter affecting the contact behavior, which determines the relationship between the contact force and the contact deformation. Among them, F n = K·δ, where K is the contact stiffness and δ is the contact deformation. The value of the contact stiffness needs to be adjusted according to the contact speed to simulate different actual physical phenomena.

[0047] In a specific embodiment, before simulating the ice-breaking situation of the vehicle when emerging from the water at different times using the optimized ice-breaking calculation model for emerging from the water, the following steps are further included: defining the boundary conditions in the optimized ice-breaking calculation model for emerging from the water; wherein, defining the boundary conditions includes adopting non-reflective boundary conditions for the periphery and the upper and lower surfaces of the water area and the air area, and adopting free boundary conditions for the periphery of the floating ice field geometric model.

[0048] Specifically, non-reflective boundary conditions are adopted for the periphery and the upper and lower surfaces of the water and air areas, and free boundary conditions are adopted for the periphery of the ice layer, which are used to simulate the vehicle emerging from the water and breaking ice in the open sea. The initial speed of the vehicle is 30 m / s, and data such as the force, acceleration, and speed of the vehicle are selected for output, and the output time interval is 1e-6 s.

[0049] In a specific embodiment, simulating the ice-breaking situation of the vehicle during different moments by using the optimized ice-breaking calculation model for the water exit to obtain the collision loads of the vehicle at different moments, including: monitoring the relative positions between the floating ice layer and the vehicle in the optimized ice-breaking calculation model for each moment by using the penalty function algorithm and the ALE algorithm; judging the penetration situation between the floating ice layer and the vehicle; if there is a penetration situation, applying a resistance force to the optimized ice-breaking calculation model to resist and eliminate the penetration situation, and obtaining the collision load based on the resistance force.

[0050] Specifically, the penalty function algorithm and the ALE algorithm are used to monitor the relative positions of the floating ice and the vehicle at each moment, judge the penetration situation, apply a force to resist and eliminate the penetration, so as to obtain the collision load at this moment, which specifically includes:

[0051] I. Monitoring the relative positions between the floating ice and the vehicle

[0052] Using the ALE algorithm to establish a dynamic model of the floating ice and the vehicle, including their shapes, sizes, material properties, etc. Set the time step to monitor the relative positions of the floating ice and the vehicle at discrete time points. Within each time step, calculate the relative positions of the floating ice and the vehicle, including the distance and direction between them. Utilize the mesh reconstruction ability of the ALE algorithm to ensure that the mesh can accurately reflect the changes when the relative positions of the floating ice and the vehicle change.

[0053] II. Judging the penetration situation

[0054] Using the penalty function algorithm to check whether there is a penetration phenomenon between the floating ice and the vehicle. This is usually achieved by comparing the actual distance between the floating ice and the vehicle with the minimum allowable distance between them. If the actual distance is less than the minimum allowable distance, it is considered that penetration has occurred. Once penetration is detected, it is necessary to evaluate the degree of penetration, including the penetration depth, area, etc. This information will be used for subsequent application of forces to resist penetration and calculation of collision loads.

[0055] III. Applying a force to resist and eliminate the penetration

[0056] According to the degree of penetration, calculate the magnitude and direction of the resistance force to be applied. This resistance force is usually achieved by introducing a contact force proportional to factors such as the penetration depth and the main surface stiffness between the floating ice and the vehicle. In the ALE algorithm, this contact force can be added as an additional external force term to the motion equations of the floating ice and the vehicle. By continuously adjusting the forces applied to the floating ice and the vehicle, gradually restore them to a state without penetration. During this process, it is necessary to continuously monitor the relative positions of the floating ice and the vehicle to ensure that the penetration is completely eliminated.

[0057] In a specific embodiment, obtaining the collision load based on the resistance includes: obtaining the collision load according to the resistance, the acceleration and the navigation speed of the vehicle at the current moment.

[0058] Specifically, after the penetration is eliminated, the collision load can be calculated based on the contact force between the floating ice and the vehicle, the acceleration and the navigation speed of the vehicle at the current moment, and the relative motion between the floating ice and the vehicle. Mechanical theories such as Newton's second law can be used for the calculation. This load usually includes components such as normal contact force and frictional force.

[0059] In a specific embodiment, after performing mesh division on the floating ice field geometric model and the vehicle model to obtain a water-breaking ice calculation model, the method further includes: obtaining the pressure value and the strain value of each floating ice unit in the floating ice field geometric model after the mesh division; wherein, the total number of floating ice units is the same as the number of meshes divided; determining whether the pressure value and the strain value of the target floating ice unit meet a preset failure criterion; the preset failure criterion is that the pressure value is less than a preset pressure standard value or the strain value is greater than a preset strain standard value; the target floating ice unit is any one of all the floating ice units; if the preset failure criterion value is met, deleting the target floating ice unit in the floating ice field geometric model after the mesh division to obtain an effective floating ice field geometric model; using the effective floating ice field geometric model as the floating ice field geometric model after the mesh division, and performing the step of defining the fluid-structure coupling relationship on the water-breaking ice calculation model to obtain an optimized water-breaking ice calculation model.

[0060] Specifically, an isotropic elastic failure constitutive model is used to simulate the floating ice, and the failure strain and the failure pressure can be set independently, and the crack propagation phenomenon of the ice can be simulated, which is closer to the real physical properties of the ice.

[0061] Specifically, the ice adopts an isotropic elastic failure constitutive model, which can set the failure pressure and the failure strain to simulate cracks, and its principle is p n+1 <p min Or Wherein, p n+1 is the pressure of the floating ice unit at a certain moment, p min is the failure pressure value of the floating ice unit, is the strain of the floating ice unit at a certain moment, is the failure strain value of the floating ice unit. When the pressure or the strain of the floating ice unit reaches the above failure criterion, the floating ice unit is deleted. The vehicle adopts an elastoplastic constitutive model, and relevant parameters such as density, shear modulus, and bulk modulus are input according to the actual material properties. Finally, the calculation termination time is set, and the entire calculation setup is checked.

[0062] Figure 4 To show the breaking process of floating ice during water emergence, it can be seen that the cracks expand rapidly in the early stage of collision, and the phenomenon of fragmentation and splashing of floating ice in the late stage of collision;

[0063] Figure 5 To show the water cushion effect generated when the vehicle emerges from the water, a high-pressure area is formed at the center of the floating ice. When cracks in the floating ice occur, the high-pressure area disappears rapidly.

[0064] Figure 6 It is the curve of the collision force and fluid-structure coupling force of the vehicle during the water-emergence ice-breaking process. It can be seen that a peak value is generated at the moment of collision. Initial cracks are formed in the floating ice before the collision. The cracks in the floating ice expand and begin to break during the collision, and the broken ice accumulates and splashes after the collision.

[0065] Based on the fluid-structure coupling theory, the present invention considers the mutual coupling effects among the vehicle, floating ice, water, and air during the water-emergence process of the vehicle. Compared with the simple flow field analysis, the method of the present invention is closer to the actual physical situation. The isotropic elastic failure constitutive model is used to simulate the floating ice, and the failure strain and failure pressure can be set by itself. The phenomenon of crack propagation in ice can be simulated, which is closer to the real physical properties of ice. At present, most of the numerical calculation methods for the water-emergence ice-breaking of vehicles consider the direct collision between the floating ice and the vehicle. The present invention considers this aspect and simultaneously establishes the whole ice and floating ice fields, which is closer to the real situation and has wide applicability.

[0066] In a specific embodiment, please refer to Figure 7 , the second embodiment of the present application provides a structural schematic diagram of a numerical calculation system for the water-emergence ice-breaking of a vehicle. The system includes: a working condition acquisition module 201, a model construction model 202, a mesh division module 203, a fluid-structure coupling relationship definition module 204, and a simulation module 205; the working condition acquisition module 201 is used to preset the working conditions of the vehicle during navigation; the working conditions include the size of the floating ice, the speed of the vehicle, the thickness of the floating ice field, and the density of the floating ice field; the model construction model 202 is used to generate a geometric model of the floating ice field according to the working conditions and construct a vehicle model of the vehicle; the mesh division module 203 is used to perform mesh division on the geometric model of the floating ice field and the vehicle model to obtain a water-emergence ice-breaking calculation model; the water-emergence ice-breaking calculation model includes the geometric model of the floating ice field after mesh division and the vehicle model after mesh division; the fluid-structure coupling relationship definition module 204 is used to define the fluid-structure coupling relationship for the water-emergence ice-breaking calculation model to obtain an optimized water-emergence ice-breaking calculation model; the simulation module 205 is used to simulate the water-emergence ice-breaking situation of the vehicle at different times by using the optimized water-emergence ice-breaking calculation model to obtain the collision load of the vehicle at different times; the collision load is the numerical value of the water-emergence ice-breaking of the vehicle.

[0067] The system in this embodiment simulates the actual situation of the vehicle during navigation by presetting the working conditions of the vehicle during navigation; generates a geometric model of the ice floe field according to the working conditions, and constructs a vehicle model of the vehicle; divides the grids of the geometric model of the ice floe field and the vehicle model to obtain a water-emerging ice-breaking calculation model; defines the fluid-structure interaction relationship for the water-emerging ice-breaking calculation model to obtain an optimized water-emerging ice-breaking calculation model; uses the optimized water-emerging ice-breaking calculation model to simulate the water-emerging ice-breaking situation of the vehicle at different times to obtain the water-emerging ice-breaking numerical values of the vehicle at different times. The definition of the fluid-structure interaction relationship can more accurately describe the interaction between the fluid and the solid, and during the water-emerging ice-breaking process, the collision, extrusion of the vehicle and the ice layer, and the subsequent ice-breaking behavior all involve complex fluid-structure interaction phenomena. Therefore, by defining the fluid-structure interaction relationship for the water-emerging ice-breaking calculation model, the accurate numerical values of the vehicle's water-emerging ice-breaking can be obtained.

[0068] In a specific embodiment, the third embodiment of the present application provides a numerical calculation device for the water-emerging ice-breaking of a vehicle, including a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor is caused to execute the steps of the method according to any one of the first embodiments of the present application.

[0069] In a specific embodiment, the fourth embodiment of the present application provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the processor is caused to execute the steps of the method according to any one of the first embodiments of the present application.

[0070] Figure 8 The internal structure diagram of a computer device in an embodiment is shown. The computer device may specifically be a terminal or a server. Please refer to Figure 8 , the computer device includes a processor, a memory, etc. connected through a system bus. Among them, the memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the computer device stores an operating system and may also store a computer program. When the computer program is executed by the processor, the processor can implement the method in this embodiment. A computer program may also be stored in the internal memory. When the computer program is executed by the processor, the processor can execute the method in this embodiment. Those skilled in the art can understand that Figure 8 the structure shown in is only a block diagram of some structures related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0071] The above embodiments only illustrate several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

[0072] As described above, it is only a preferred embodiment of the present invention, and it is not a limitation to the present invention in other forms. Any person skilled in the art may use the disclosed technical content to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A numerical calculation method for a navigation body breaking ice when leaving water, characterized in that: The method comprises: Preset the working conditions of the navigation body during navigation; the working conditions include the size of floating ice, the speed of the navigation body, the thickness of the floating ice field and the density of the floating ice field; Generate a floating ice field geometric model according to the working conditions, and construct a navigation body model of the navigation body; Meshing the floating ice field geometric model and the navigation body model to obtain a water-out and ice-breaking calculation model; the water-out and ice-breaking calculation model includes the meshed floating ice field geometric model and the meshed navigation body model; Defining the fluid-solid coupling relationship of the water-outlet and ice-breaking calculation model to obtain an optimized water-outlet and ice-breaking calculation model; The optimized water-out and ice-breaking calculation model is used to simulate the water-out and ice-breaking conditions of the navigation body at different times to obtain the collision load of the navigation body at different times; the collision load is the water-out and ice-breaking value of the navigation body.

2. The numerical calculation method for breaking ice when a navigation body leaves the water according to claim 1, characterized in that: The step of defining the fluid-solid coupling relationship of the water-outlet and ice-breaking calculation model to obtain an optimized water-outlet and ice-breaking calculation model includes: The ice field geometric model after meshing and the navigation body model after meshing are described by Lagrangian mesh; The water area and air area in the water-outlet icebreaking calculation model are described by using Euler grid; The fluid-solid coupling relationship is used to simulate the navigation body model after meshing, the floating ice field geometric model after meshing, and the fluid-solid coupling effect between the water area and the air domain to obtain the optimized water-out icebreaking calculation model.

3. The numerical calculation method for breaking ice when a navigation body leaves the water according to claim 1, characterized in that: Before simulating the water-out and ice-breaking conditions of the navigation body at different times by using the optimized water-out and ice-breaking calculation model, the method further includes: Defining the contact relationship in the optimized water-outlet icebreaking calculation model; Wherein, defining the contact relationship includes defining the contact relationship and the erosion contact deformation relationship between the floating ice layer and the water area in the optimized water-breaking ice calculation model.

4. The numerical calculation method for breaking ice when a navigation body leaves the water according to claim 1, characterized in that: Before simulating the water-out and ice-breaking conditions of the navigation body at different times by using the optimized water-out and ice-breaking calculation model, the method further includes: Defining boundary conditions in the optimized water-outlet icebreaking calculation model; The boundary conditions are defined as follows: the periphery and upper and lower surfaces of the water area and the air area adopt non-reflecting boundary conditions, and the periphery of the floating ice field geometric model adopts free boundary conditions.

5. The numerical calculation method for the water-breaking ice of a navigation body according to claim 1, characterized in that: The method of simulating the water-out and ice-breaking conditions of the navigation body at different times by using the optimized water-out and ice-breaking calculation model to obtain the collision load of the navigation body at different times includes: The penalty function algorithm and the ALE algorithm are used to monitor the relative position between the floating ice layer and the navigation body in the optimized water-breaking ice calculation model at each moment; Determine the penetration situation of the relative position between the ice layer and the navigation body; If a penetration situation exists, a resistance force is applied to the optimized water-out-of-ice breaking calculation model to resist and eliminate the penetration situation, and the collision load is obtained based on the resistance force.

6. The numerical calculation method for breaking ice when a navigation body leaves the water according to claim 5, characterized in that: The obtaining of the collision load based on the resistance force comprises: The collision load is obtained according to the resistance force, the acceleration and navigation speed of the navigation body at the current moment.

7. The numerical calculation method for breaking ice when a navigation body leaves water according to claim 1, characterized in that: After meshing the floating ice field geometric model and the navigation body model to obtain the water-out and ice-breaking calculation model, the method further includes: Obtaining the pressure value and strain value of each floating ice unit in the floating ice field geometric model after the grid division; wherein the total number of floating ice units is the same as the number of divided grids; Determine whether the pressure value and the strain value of the target floating ice unit meet a preset failure standard; the preset failure standard is that the pressure value is less than a preset pressure standard value or the strain value is greater than a preset strain standard value; the target floating ice unit is any one of all the floating ice units; If the preset failure standard value is met, deleting the target floating ice unit in the floating ice field geometric model after the grid division, so as to obtain a valid floating ice field geometric model; The effective floating ice field geometric model is used as the floating ice field geometric model after the mesh division, and the step of defining the fluid-solid coupling relationship of the water-outlet icebreaking calculation model is performed to obtain the optimized water-outlet icebreaking calculation model.

8. A numerical calculation system for a navigation body breaking ice when leaving water, characterized in that: The system comprises: a working condition acquisition module, a model building model, a meshing module, a fluid-solid coupling relationship definition module and a simulation module; The working condition acquisition module is used to preset the working conditions of the navigation body during navigation; the working conditions include the size of floating ice, the speed of the navigation body, the thickness of the floating ice field and the density of the floating ice field; The model building model is used to generate a floating ice field geometric model according to the working conditions and to build a navigation body model of the navigation body; The grid division module is used to grid the floating ice field geometric model and the navigation body model to obtain a water-out and ice-breaking calculation model; the water-out and ice-breaking calculation model includes the grid-divided floating ice field geometric model and the grid-divided navigation body model; The fluid-solid coupling relationship definition module is used to define the fluid-solid coupling relationship of the water-outlet and ice-breaking calculation model to obtain an optimized water-outlet and ice-breaking calculation model; The simulation module is used to simulate the water-out and ice-breaking conditions of the navigation body at different times using the optimized water-out and ice-breaking calculation model to obtain the collision load of the navigation body at different times; the collision load is the water-out and ice-breaking value of the navigation body.

9. A numerical computing device for a navigation body breaking ice when leaving water, comprising a memory and a processor, characterized in that: The memory stores a computer program, and when the computer program is executed by the processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 7.

Images