Heat dissipation improvement design method and system of protection tube

Abstract

The invention provides a heat dissipation improvement design method and system for a protection tube, and the method comprises the steps: obtaining environment load data based on a historical protection tube operation database; constructing a multi-physics field coupling simulation model; acquiring temperature distribution characteristics of the protection tube in different environments; obtaining stress distribution characteristics of the protection tube under different load combination working conditions; obtaining a plurality of different protection tube heat dissipation improvement design schemes and protection tube structural strength evaluation results; and screening the plurality of different protection tube heat dissipation improvement design schemes to obtain a protection tube heat dissipation improvement design result meeting a preset protection requirement. The problem that the protection effect of the protection tube is poor due to the fact that only the hole opening heat dissipation design of the protection tube is considered and the reduction of the structural performance of the protection tube is not considered in the prior art is solved. According to the invention, a plurality of dimensions such as temperature and stress are provided for the heat dissipation design of the protection tube for design evaluation, and the protection effect of the protection tube is improved.

Description

Technical Field

[0001] The invention relates to the field of submarine cable protection design, and in particular to a heat dissipation improvement design method and system for a protection tube. Background Art

[0002] Submarine cables are the link between offshore substations and onshore control centers. To improve the operational reliability of submarine cables, protection tubes are needed to protect the submarine cables that rise from the seabed to the offshore substations. The protection tubes used in the prior art are usually submarine cable J-tubes. The design concept of submarine cable J-tubes is safety, reliability, easy maintenance and durability, and mainly considers the protection effect of submarine cables and the structural performance of the J-tubes themselves.

[0003] At present, the design of submarine cable J-tube mainly adopts the attempt of opening holes on the J-tube to achieve the purpose of optimizing the structural design of the J-tube and improving the heat dissipation conditions of the submarine cable in the tube. However, the opening of the J-tube will inevitably cause the structural performance of the component itself to decline, and it is possible that the J-tube structure will fail after the opening and lose the protection effect on the submarine cable. In addition, there are technical studies that propose a current-carrying capacity evaluation model for submarine cables in J-tubes based on finite element simulation. In COMSOL software, a geometric model is built based on a real operating scenario, material properties (thermal conductivity and density) are loaded, and boundary conditions (wind speed near the J-tube, solar radiation intensity and ambient temperature) are set to form a three-dimensional temperature field simulation model of the J-tube and the submarine cable, so as to accurately solve the temperature of the submarine cable conductor in the tube and then carry out an evaluation of the current-carrying capacity of the submarine cable in the tube. Therefore, the existing technical system lacks attention to the problem of the decline in the structural performance of the J-tube after the opening of the J-tube, and cannot answer how to determine the improved design scheme for the heat dissipation of the submarine cable J-tube to achieve the optimization of the overall performance of the submarine cable J-tube, that is, to maximize the current-carrying capacity of the submarine cable in the J-tube while ensuring that the submarine cable J-tube has sufficient structural strength. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a heat dissipation improvement design method and system for a protection tube, which realizes design evaluation of the heat dissipation design of the protection tube in multiple dimensions such as temperature and stress, thereby improving the protection effect of the protection tube.

[0005] To achieve the above object, an embodiment of the present invention provides a method for improving heat dissipation design of a protection tube, comprising:

[0006] Based on the historical protection pipe operation database, environmental load data is obtained; wherein the environmental load data includes: temperature field data, fluid field data and stress field data;

[0007] Based on the environmental load data, construct a multi-physics field coupling simulation model;

[0008] Based on the temperature field data, the fluid field data and the multi-physics field coupling simulation model, obtaining temperature distribution characteristics of the protection tube under different environments;

[0009] Based on the preset superposition algorithm, the stress field data and the multi-physics field coupling simulation model, the stress distribution characteristics of the protective pipe under different load combination conditions are obtained;

[0010] Based on the temperature distribution characteristics of the protection tube under the different environments and the stress distribution characteristics of the protection tube under different load combination conditions, several different protection tube heat dissipation improvement design schemes and protection tube structural strength assessment results are obtained;

[0011] Based on the protection tube structural strength assessment result, several different protection tube heat dissipation improvement design solutions are screened to obtain protection tube heat dissipation improvement design results that meet preset protection requirements.

[0012] The embodiment of the present invention proposes a method for improving the heat dissipation design of a protection tube. By obtaining environmental load data as basic data, fully considering temperature field data, fluid field data and stress field data, and then analyzing the coupling effect of multiple physical fields, the fluid data outside the protection tube can be introduced into the tube while ensuring that the protection tube has sufficient structural strength, thereby greatly improving the operating environment of the submarine cable in the tube and thus preventing the overheating problem of the protection tube section. Finally, the heat dissipation design of the protection tube is evaluated and analyzed through the temperature distribution characteristics of the protection tube under different environments and the stress distribution characteristics of the protection tube under different load combination conditions. By analyzing the overall performance of the protection tube under different heat dissipation improvement design schemes of the protection tube, the optimal heat dissipation improvement design scheme of the protection tube that meets the transmission capacity demand of the submarine cable system is finally determined, so that the heat dissipation design of the protection tube is designed and evaluated in multiple dimensions such as temperature and stress, thereby improving the protection effect of the protection tube.

[0013] Furthermore, based on the environmental load data, a multi-physics field coupling simulation model is constructed, specifically:

[0014] Based on the design parameters of the protection tube, a geometric model of the protection tube is constructed;

[0015] Based on the protection tube geometric model, the material properties of each layer structure setting of the protection tube geometric model are obtained through simulation model analysis;

[0016] Based on the environmental load data, the temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions are set respectively; wherein the temperature field boundary conditions include: the setting of heat source, convection heat dissipation coefficient, solar radiation intensity and ambient temperature; the fluid field boundary conditions include: the setting of flow velocity and pressure; the stress field boundary conditions include: the setting of wind load, wave load, ocean current load and gravity load;

[0017] Based on the layer structures of the protective tube geometric model, material properties, temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions are set to construct a multi-physics field coupling simulation model.

[0018] Furthermore, based on the temperature field data, the fluid field data and the multi-physics field coupling simulation model, the temperature distribution characteristics of the protection tube under different environments are obtained, specifically:

[0019] Inputting the temperature field data and the fluid field data into the multi-physics field coupling simulation model respectively to calculate the temperature distribution data of the protection tube;

[0020] Based on the protection tube temperature distribution data, protection tube temperature distribution characteristics under different environments are constructed.

[0021] Furthermore, based on the preset superposition algorithm, the stress field data and the multi-physics field coupling simulation model, the stress distribution characteristics of the protective pipe under different load combination conditions are obtained, specifically:

[0022] Based on the preset superposition algorithm, several superposition results are obtained by superimposing the maximum value of the load in the rotation stress field data with the load value of the residual stress field data;

[0023] Based on the several superposition results, construct a load combination condition;

[0024] The load combination working condition is input into the multi-physics field coupling simulation model to obtain the stress distribution characteristics of the protective pipe under different load combination working conditions.

[0025] Furthermore, based on the preset superposition algorithm, the maximum value of the load in the rotation stress field data is superimposed with the load value of the residual stress field data to obtain several superposition results, specifically:

[0026] Based on the stress field data, the maximum value of each load is obtained;

[0027] The maximum values ​​of each load and their corresponding residual stress field data load values ​​are superimposed by the Turkstra superposition algorithm to obtain several superposition results; wherein the residual stress field data load value is specifically: in one superposition operation, the value of all remaining loads obtained by eliminating the load whose maximum value is read in rotation.

[0028] Furthermore, it also includes:

[0029] Obtain the mass matrix, damping matrix and stiffness matrix of the protection pipe structure;

[0030] Based on the first-order natural frequency and second-order natural frequency of the protection tube structure, the mass damping coefficient and stiffness damping coefficient are calculated;

[0031] Constructing a Rayleigh damping coefficient based on the mass matrix, the damping matrix stiffness matrix, the mass damping coefficient and the stiffness damping coefficient;

[0032] Based on the Rayleigh damping coefficient, the load combination working condition is input into the multi-physics field coupling simulation model to obtain the stress distribution characteristics of the protection pipe under different load combination working conditions.

[0033] Furthermore, based on the temperature distribution characteristics of the protection tube under the different environments and the stress distribution characteristics of the protection tube under different load combination conditions, several different protection tube heat dissipation improvement design schemes and protection tube structural strength assessment results are obtained, specifically:

[0034] Based on the temperature distribution characteristics of the protection tube under the different environments, the key focus areas of the protection tube heat dissipation improvement design are obtained;

[0035] By analyzing the key areas of the heat dissipation improvement design of the protection tube, several different heat dissipation improvement design schemes for the protection tube are obtained;

[0036] Based on the stress distribution characteristics of the protection pipe under the different load combination working conditions, the yield failure damage of the protection pipe is judged to obtain the structural strength assessment result of the protection pipe.

[0037] Furthermore, based on the protection tube structural strength evaluation result, several different protection tube heat dissipation improvement design schemes are screened to obtain the protection tube heat dissipation improvement design results that meet the preset protection requirements, specifically:

[0038] Based on the protection tube structural strength assessment result, the several different protection tube heat dissipation improvement design schemes are verified to obtain the structural strength verification results of the several different protection tube heat dissipation improvement design schemes;

[0039] By screening the structural strength verification results of the several different protection tube heat dissipation improvement design schemes, the protection tube heat dissipation improvement design result that meets the load increase demand and has the highest structural safety margin is obtained.

[0040] The embodiment of the present invention also provides a heat dissipation improvement design system for a protection tube, comprising: a data acquisition module, a model building module, a temperature distribution feature acquisition module, a stress distribution feature acquisition module, a design evaluation module and a result screening module;

[0041] The data acquisition module is used to acquire environmental load data based on the historical protection pipe operation database; wherein the environmental load data includes: temperature field data, fluid field data and stress field data;

[0042] The model building module is used to build a multi-physics field coupling simulation model based on the environmental load data;

[0043] The temperature distribution feature acquisition module is used to acquire the temperature distribution features of the protection tube under different environments based on the temperature field data, the fluid field data and the multi-physics field coupling simulation model;

[0044] The stress distribution feature acquisition module is used to acquire the stress distribution features of the protection pipe under different load combination conditions based on a preset superposition algorithm, the stress field data and the multi-physical field coupling simulation model;

[0045] The design evaluation module is used to obtain several different heat dissipation improvement design schemes for the protection tube and the protection tube structural strength evaluation results based on the temperature distribution characteristics of the protection tube under the different environments and the stress distribution characteristics of the protection tube under different load combination working conditions;

[0046] The result screening module is used to screen the several different protection tube heat dissipation improvement design schemes based on the protection tube structural strength evaluation result, and obtain the protection tube heat dissipation improvement design result that meets the preset protection requirements.

[0047] The embodiment of the present invention proposes a heat dissipation improvement design system for a protection tube. The environmental load data is obtained as basic data through a data acquisition module, and the temperature field data, fluid field data and stress field data are fully considered. Then, the coupling effect of multiple physical fields is analyzed through a model construction module, a temperature distribution feature acquisition module and a stress distribution feature acquisition module. The fluid data outside the protection tube can be introduced into the tube while ensuring that the protection tube has sufficient structural strength, which greatly improves the operating environment of the submarine cable in the tube and thus prevents the overheating problem of the protection tube section. Finally, the heat dissipation design of the protection tube is evaluated and analyzed by the temperature distribution characteristics of the protection tube under different environments and the stress distribution characteristics of the protection tube under different load combination conditions through a design evaluation module and a result screening module. By analyzing the overall performance of the protection tube under different heat dissipation improvement design schemes of the protection tube, the optimal heat dissipation improvement design scheme of the protection tube that meets the transmission capacity requirement of the submarine cable system is finally determined, so that the heat dissipation design of the protection tube is evaluated in multiple dimensions such as temperature and stress, thereby improving the protection effect of the protection tube.

[0048] The model building module is used to build a multi-physics field coupling simulation model based on the environmental load data, and also includes:

[0049] A geometric model building unit, a property analysis unit, a condition setting unit and a simulation model building unit;

[0050] The geometric model building unit is used to build a geometric model of the protection tube based on the design parameters of the protection tube;

[0051] The property analysis unit is used to obtain the material properties of each layer structure setting of the protection tube geometric model through simulation model analysis based on the protection tube geometric model;

[0052] The condition setting unit is used to set the temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions respectively based on the environmental load data; wherein the temperature field boundary conditions include: settings for heat source, convection heat dissipation coefficient, solar radiation intensity and ambient temperature; the fluid field boundary conditions include: settings for flow velocity and pressure; the stress field boundary conditions include: settings for wind load, wave load, ocean current load and gravity load;

[0053] The simulation model building unit is used to set material properties, temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions based on each layer structure of the protection tube geometric model to build a multi-physical field coupling simulation model. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A schematic flow chart of the steps of a method for improving heat dissipation design of a protection tube provided in one embodiment of the present invention;

[0055] Figure 2 A main view and simulation conditions of a multi-physics field coupling simulation model of a heat dissipation improvement design method for a protection tube provided by a certain embodiment of the present invention;

[0056] Figure 3 A top view and simulation conditions of a multi-physics field coupling simulation model of a heat dissipation improvement design method for a protection tube provided in a certain embodiment of the present invention;

[0057] Figure 4 A schematic diagram of temperature distribution of a heat dissipation improvement design method for a protection tube provided in one embodiment of the present invention;

[0058] Figure 5 A schematic diagram of stress distribution of a heat dissipation improvement design method for a protection tube provided in a certain embodiment of the present invention;

[0059] Figure 6 A schematic diagram of the module structure of a heat dissipation improvement design system for a protection tube provided in one embodiment of the present invention;

[0060] Figure 7 A schematic diagram of the structure of a model building module of a heat dissipation improvement design system for a protection tube provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] The submarine cable J-tube may face various forms of damage throughout its life cycle, including external force collision damage caused by submarine cable collision during the laying of submarine cable through the tube, corrosion damage caused by high humidity, high salinity, and marine organisms, yield deformation damage caused by local stress concentration, fatigue damage and resonance damage caused by long-term fluctuating loads. For the improved design of the J-tube, it is necessary to have sufficient structural strength to resist various forms of damage within the design operating life. At the same time, due to the frequent occurrence of abnormal environmental events such as typhoons and earthquakes in recent years, the structural strength verification under extreme environmental conditions must also be considered in the process of improving the design of the submarine cable J-tube structure. The existing technical system only proposes that the opening of the J-tube wall can improve the current carrying capacity of the submarine cable in the tube and discusses the influence of the opening parameters of the J-tube wall on the improvement of the current carrying capacity of the submarine cable in the tube, but no recommended design scheme for improving the heat dissipation of the submarine cable J-tube has been formed. The existing technical system lacks attention to the problem of the decline in the structural performance of the J-tube after the opening of the J-tube, and cannot answer how to determine the design scheme for improving the heat dissipation of the submarine cable J-tube to achieve the optimization of the overall performance of the submarine cable J-tube, that is, to maximize the current carrying capacity of the submarine cable in the J-tube while ensuring that the submarine cable J-tube has sufficient structural strength. Therefore, it is necessary to propose an improved design method for the heat dissipation of the submarine cable J-tube based on the temperature-fluid-stress multi-physical field coupling analysis, which can solve the thermal bottleneck problem of the submarine cable J-tube section while ensuring that the submarine cable J-tube has sufficient structural strength, so as to improve the overall transmission capacity of the submarine cable sending system of the offshore booster station without increasing the investment cost of the submarine cable.

[0063] Based on the above description, in this embodiment, a submarine cable J tube is used as a protection tube to explain the heat dissipation improvement design method of a protection tube proposed by the present invention, which will not be repeated below.

[0064] Example 1

[0065] See also Figure 1 , Figure 1 A schematic flow chart of the steps of a heat dissipation improvement design method for a protection tube provided in one embodiment of the present invention. Figure 1 As shown, the embodiment of the present invention provides a heat dissipation improvement design method for a protection tube, including steps 101 to 106, each of which is specifically as follows:

[0066] Step 101, based on the historical protection pipe operation database, obtain environmental load data; wherein the environmental load data includes: temperature field data, fluid field data and stress field data;

[0067] As an example of this embodiment, the types of environmental loads faced by the submarine cable J-tube during operation are determined, the calculation methods of the numerical values ​​of various environmental loads are given, and a modeling method of the combined action model of multiple environmental loads of the submarine cable J-tube is proposed to determine the typical load combination working conditions of the submarine cable J-tube, which is used for the input of the temperature-fluid-stress multi-physical field coupling simulation model.

[0068] The wind speed data corresponding to different heights of the J-tube section of the submarine cable above sea level are collected, and the J-tube section of the submarine cable above sea level is divided into n sections according to the wind speed range. The value of n is selected according to the accuracy requirements of the wind load distribution calculation results. For each section of the divided J-tube submarine cable, its wind load F w The calculation formula is as follows:

[0069] F w =KK h a w v

[0070] Where: K is the wind load shape factor, K h is the wind pressure height variation coefficient, a w is the wind pressure coefficient, v is the maximum value of the wind speed range corresponding to the J tube of this section of submarine cable, and A is the contour projection area perpendicular to the wind direction.

[0071] For the J-tube section of the submarine cable below sea level, since its diameter is much smaller than its length, its wave load F h The calculation formula is as follows:

[0072]

[0073] Where: ρ is the density of seawater, C D , C M are the drag force coefficient and inertia force coefficient respectively, D is the diameter of the J tube, v x is the horizontal velocity of the water particle. In addition, for the J-tube portion of the submarine cable below sea level, the current load F caused by the horizontal ocean current also needs to be considered. c , and its calculation formula is as follows:

[0074]

[0075] Among them: A c is the projected area perpendicular to the flow direction, v c is the ocean current velocity.

[0076] The above is the calculation formula for part of the stress field data. The temperature field and fluid field data can be obtained through existing means.

[0077] Step 102, constructing a multi-physics field coupling simulation model based on the environmental load data;

[0078] As an example of this embodiment, a geometric model of the protection tube is constructed based on the design parameters of the protection tube;

[0079] Based on the geometric model of the protective tube, the material properties of each layer structure of the protective tube geometric model are obtained through simulation model analysis; based on the environmental load data, the temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions are set respectively; wherein, the temperature field boundary conditions include: the setting of heat source, convection heat dissipation coefficient, solar radiation intensity and ambient temperature; the fluid field boundary conditions include: the setting of flow velocity and pressure; the stress field boundary conditions include: the setting of wind load, wave load, current load and gravity load; based on the material properties, temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions of each layer structure of the protective tube geometric model, a multi-physics field coupling simulation model is constructed. A specific implementation method is to establish a temperature-fluid-stress multi-physics field coupling simulation model of the J tube section of the submarine cable (including the J tube and the submarine cable in the tube) based on the different types of environmental loads obtained in step 101, and use the different environmental loads calculated by S1 as the simulation stress field input, and use the simulation model to analyze the hot spot temperature distribution characteristics of the submarine cable in the J tube under different operation scenarios, and propose a design idea for improving the heat dissipation of the submarine cable J tube. See. Figure 2 and Figure 3 , Figure 2 A main view and simulation conditions of a multi-physics field coupling simulation model of a heat dissipation improvement design method for a protection tube provided by a certain embodiment of the present invention; Figure 3 A top view and simulation conditions of a multi-physics field coupling simulation model of a heat dissipation improvement design method for a protection tube provided in a certain embodiment of the present invention; Figure 2 and Figure 3 As shown, a geometric model of the J-tube section of the submarine cable is built in the simulation software based on the design parameters of the J-tube and the structural parameters of the submarine cable. The material properties of each layer of the geometric model of the J-tube section of the submarine cable are set in the simulation software according to the real material parameters. Based on the actual operation of the J-tube section of the submarine cable, the temperature field, fluid field and stress field are added in the simulation software, and the boundary conditions of different physical fields are set respectively (the temperature field boundary conditions include the settings of the heat source, convection heat dissipation coefficient, solar radiation intensity and ambient temperature, the fluid field boundary conditions include the settings of the flow velocity and pressure, and the stress field includes the settings of the wind load, wave load, current load and gravity load), and finally a temperature-fluid-stress multi-physical field coupling simulation model of the J-tube section of the submarine cable is formed.

[0080] Step 103, based on the temperature field data, the fluid field data and the multi-physics field coupling simulation model, obtaining temperature distribution characteristics of the protection tube under different environments;

[0081] As an example of this embodiment, the temperature field data and the fluid field data are respectively input into the multi-physics field coupling simulation model to calculate the temperature distribution data of the protection tube; based on the temperature distribution data of the protection tube, the temperature distribution characteristics of the protection tube under different environments are constructed. For a specific possible implementation method, see Figure 4 , Figure 4 A schematic diagram of temperature distribution of a heat dissipation improvement design method for a protection tube provided in a certain embodiment of the present invention; Figure 4 As shown in the figure, the temperature distribution of the J-tube section of the submarine cable under different environmental conditions (wind speed, ambient temperature and solar radiation intensity) is calculated by using the temperature-fluid-stress multi-physics field coupling simulation model. Based on the analysis of the hot spot temperature distribution characteristics of the conductor in the J-tube section of the submarine cable, the key focus areas of the improved heat dissipation design of the submarine cable J-tube are determined, and a method for evaluating the benefits of different improved heat dissipation design schemes of the J-tube of the submarine cable (different J-tube opening distributions and different aperture sizes) on improving the current-carrying capacity of the J-tube section of the submarine cable is proposed.

[0082] Step 104, based on a preset superposition algorithm, the stress field data and the multi-physics field coupling simulation model, obtaining stress distribution characteristics of the protection pipe under different load combination conditions;

[0083] As an example of this embodiment, based on a preset superposition algorithm, by superimposing the maximum value of the load in the rotation stress field data with the residual stress field data load value, several superposition results are obtained; based on the several superposition results, a load combination condition is constructed; the load combination condition is input into the multi-physics field coupling simulation model to obtain the stress distribution characteristics of the protective pipe under different load combination conditions. Based on the stress field data, the maximum value of each load is obtained; through the Turkstra superposition algorithm, the maximum value of each load and its corresponding residual stress field data load value are superimposed to obtain several superposition results; wherein, the residual stress field data load value is specifically: in a superposition operation, the value of all remaining loads obtained by eliminating the load whose maximum value is read in rotation. It also includes: obtaining the mass matrix, damping matrix and stiffness matrix of the protection tube structure; calculating the mass damping coefficient and stiffness damping coefficient based on the first-order natural frequency and second-order natural frequency of the protection tube structure; constructing the Rayleigh damping coefficient based on the mass matrix, damping matrix stiffness matrix, mass damping coefficient and stiffness damping coefficient; based on the Rayleigh damping coefficient, inputting the load combination working condition into the multi-physics field coupling simulation model to obtain the stress distribution characteristics of the protection tube under different load combination working conditions. For a specific implementation method, see Figure 5 , Figure 5 A schematic diagram of stress distribution of a heat dissipation improvement design method for a protection tube provided by a certain embodiment of the present invention; Figure 5As shown in the figure, based on the historical monitoring data of the offshore booster station wind speed sensor and the J-tube seawater section stress sensor, the gravity load, wave load and current load under different recurrence periods and the wind load under different typhoon levels are determined. According to the Turkstra superposition principle, the maximum value of a certain load in the design reference period is superimposed with the instantaneous value of other loads in turn. On this basis, the influence of offshore structural damping is considered, including hydrodynamic damping, structural damping, soil damping, etc., and various damping factors are taken into account by inputting the Rayleigh damping coefficient in the simulation.

[0084] C=x 1 A+x 2 B

[0085]

[0086] Where A, C, and B are mass matrix, damping matrix, and stiffness matrix; x 1 、x 2 is the mass damping coefficient and stiffness damping coefficient; ξ is the damping ratio of the structure; f 1 、f 2 are the first and second order natural frequencies of the structure.

[0087] In view of the multi-environmental load combination scenarios that the submarine cable J-tube may face during operation, the typical load combination conditions of the submarine cable J-tube are determined based on the Turkstra superposition principle as input in the evaluation of the structural performance of the submarine cable J-tube. The method for determining the typical load combination conditions of the submarine cable J-tube is as follows:

[0088] F 1 =maxF w (t)+F h (t * )+F c (t * )

[0089] F 2 =F w (t * )+maxF h (t)+F c (t * )

[0090] F 3 =F w (t * )+F h (t * )+maxF c (t)

[0091] Among them: F 1 、F 2 、F 3are three typical load combination conditions of submarine cable J tubes, maxF i (t) is the maximum value of the i-th load, F i (t*) is the instantaneous value of the ith load.

[0092] The combined working condition load obtained by superposition is used as the input of the multi-physical field coupling simulation model of the submarine cable J-tube section to calculate the stress distribution of the submarine cable J-tube under different typical load combination working conditions, and then the hot spot stress of the submarine cable J-tube is obtained through the simulation model calculation result in step 102 to determine whether the local structure of the submarine cable J-tube has yield failure damage under the most unfavorable load effect, thereby forming an evaluation method for the structural strength of the submarine cable J-tube under the most unfavorable load effect.

[0093] As another example of this embodiment, for the improved design method of heat dissipation of submarine cable J-tube based on temperature-fluid-stress multi-physical field coupling analysis, in terms of using Turkstra superposition principle to determine the typical load combination working condition of submarine cable J-tube, JC superposition principle can be used instead of Turkstra superposition principle, and the purpose of the invention can be achieved through subsequent processing of this technical solution; in analyzing different improved design schemes for heat dissipation of submarine cable J-tube (for improving the current carrying capacity of submarine cable J-tube section, the equivalent thermal path method can be used instead of the simulation analysis method, but the difficulty of solving will be greatly increased, and the accuracy of solving will be difficult to guarantee.

[0094] Step 105, based on the temperature distribution characteristics of the protection tube under the different environments and the stress distribution characteristics of the protection tube under different load combination working conditions, obtain several different protection tube heat dissipation improvement design schemes and protection tube structural strength assessment results;

[0095] As an example of this embodiment, based on the temperature distribution characteristics of the protective tube under the different environments, the key focus areas of the heat dissipation improvement design of the protective tube are obtained; by analyzing the key focus areas of the heat dissipation improvement design of the protective tube, several different heat dissipation improvement design schemes for the protective tube are obtained; based on the stress distribution characteristics of the protective tube under the different load combination working conditions, the yield failure damage of the protective tube is determined to obtain the structural strength assessment result of the protective tube. A specific explanation is that step 103 combines the hot spot temperature obtained in step 104 to obtain the hot spot stress of the submarine cable J tube, and forms an assessment method for the structural strength of the submarine cable J tube under the most unfavorable load effect. For submarine cable systems with different transmission capacity requirements, the different J tube opening distributions, different aperture sizes, and other submarine cable J tube section current carrying capacity improvement benefit assessment methods proposed in steps 2 to 104 are used to determine different submarine cable J tube heat dissipation improvement design schemes that can meet the submarine cable transmission capacity requirements.

[0096] Step 106 , based on the protection tube structural strength evaluation result, the plurality of different protection tube heat dissipation improvement design solutions are screened to obtain a protection tube heat dissipation improvement design result that meets the preset protection requirements.

[0097] As an example of this embodiment, based on the protection tube structural strength assessment result, the several different protection tube heat dissipation improvement design schemes are verified to obtain the structural strength verification results of the several different protection tube heat dissipation improvement design schemes; by screening the structural strength verification results of the several different protection tube heat dissipation improvement design schemes, the protection tube heat dissipation improvement design result that meets the load increase demand and has the highest structural safety margin is obtained. A specific explanation is that by combining the J-tube section current carrying capacity improvement benefit assessment method in steps 102 to 104 and the J-tube structural strength assessment method in step 105, and using the submarine cable J-tube structural strength assessment method based on the combined working condition load proposed in step 105 to verify the structural strength of the J-tube under different heat dissipation improvement design schemes, the J-tube heat dissipation improvement design scheme with the highest structural safety margin under the premise of meeting the load increase demand of the submarine cable in the J-tube is determined, thereby realizing the dynamic capacity increase of the J-tube under the premise of protecting the submarine cable.

[0098] The proposed improved design method for heat dissipation of submarine cable J-tubes not only improves the current carrying capacity of submarine cable in the tube by optimizing the heat dissipation conditions of submarine cable in the tube, but also fully considers the influence of structural changes of submarine cable J-tubes on their own structural performance, and finally achieves the goal of maximizing the current carrying capacity of submarine cable in J-tubes under the premise of ensuring that submarine cable J-tubes have sufficient structural strength. A temperature-fluid-stress multi-physics field coupling simulation model of submarine cable J-tube sections is established, and a benefit evaluation method for improving the current carrying capacity of submarine cable J-tube sections and a structural strength evaluation method for submarine cable J-tubes are proposed based on the simulation model, and the overall performance of J-tubes under different submarine cable J-tube heat dissipation improvement design schemes is analyzed, and finally the optimal submarine cable J-tube heat dissipation improvement design scheme that meets the transmission capacity requirements of the submarine cable system is determined.

[0099] The embodiment of the present invention proposes a method for improving the heat dissipation design of a protection tube. By obtaining environmental load data as basic data, fully considering temperature field data, fluid field data and stress field data, and then analyzing the coupling effect of multiple physical fields, the fluid data outside the protection tube can be introduced into the tube while ensuring that the protection tube has sufficient structural strength, thereby greatly improving the operating environment of the submarine cable in the tube and thus preventing the overheating problem of the protection tube section. Finally, the heat dissipation design of the protection tube is evaluated and analyzed through the temperature distribution characteristics of the protection tube under different environments and the stress distribution characteristics of the protection tube under different load combination conditions. By analyzing the overall performance of the protection tube under different heat dissipation improvement design schemes of the protection tube, the optimal heat dissipation improvement design scheme of the protection tube that meets the transmission capacity demand of the submarine cable system is finally determined, so that the heat dissipation design of the protection tube is designed and evaluated in multiple dimensions such as temperature and stress, thereby improving the protection effect of the protection tube.

[0100] Example 2

[0101] See also Figure 6, Figure 6 A schematic diagram of the module structure of a heat dissipation improvement design system for a protection tube provided by a certain embodiment of the present invention; Figure 6 As shown, the embodiment of the present invention proposes a heat dissipation improvement design system for a protection tube, including: a data acquisition module 601, a model building module 602, a temperature distribution feature acquisition module 603, a stress distribution feature acquisition module 604, a design evaluation module 605 and a result screening module 606;

[0102] The data acquisition module 601 is used to acquire environmental load data based on the historical protection pipe operation database; wherein the environmental load data includes: temperature field data, fluid field data and stress field data;

[0103] The model building module 602 is used to build a multi-physics field coupling simulation model based on the environmental load data;

[0104] As an example of this embodiment, see Figure 7 , Figure 7 A schematic diagram of a model building module structure of a heat dissipation improvement design system for a protection tube provided by a certain embodiment of the present invention. Figure 7 As shown, the model building module 602 is used to build a multi-physics field coupling simulation model based on the environmental load data, and also includes:

[0105] A geometric model building unit 701, a property analysis unit 702, a condition setting unit 703 and a simulation model building unit 704;

[0106] The geometric model building unit 701 is used to build a geometric model of the protection tube based on the design parameters of the protection tube;

[0107] The property analysis unit 702 is used to obtain the material properties of each layer structure setting of the protection tube geometric model through simulation model analysis based on the protection tube geometric model;

[0108] The condition setting unit 703 is used to set the temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions respectively based on the environmental load data; wherein the temperature field boundary conditions include: the setting of heat source, convection heat dissipation coefficient, solar radiation intensity and ambient temperature; the fluid field boundary conditions include: the setting of flow velocity and pressure; the stress field boundary conditions include: the setting of wind load, wave load, ocean current load and gravity load;

[0109] The simulation model building unit 704 is used to set material properties, temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions based on each layer structure of the protection tube geometric model to build a multi-physical field coupling simulation model.

[0110] The temperature distribution feature acquisition module 603 is used to acquire the temperature distribution features of the protection tube under different environments based on the temperature field data, the fluid field data and the multi-physics field coupling simulation model;

[0111] The stress distribution feature acquisition module 604 is used to acquire the stress distribution features of the protection pipe under different load combination conditions based on a preset superposition algorithm, the stress field data and the multi-physics field coupling simulation model;

[0112] The design evaluation module 605 is used to obtain several different heat dissipation improvement design schemes for the protection tube and the protection tube structural strength evaluation results based on the temperature distribution characteristics of the protection tube under the different environments and the stress distribution characteristics of the protection tube under different load combination working conditions;

[0113] The result screening module 606 is used to screen the several different protection tube heat dissipation improvement design solutions based on the protection tube structure strength evaluation result, and obtain the protection tube heat dissipation improvement design result that meets the preset protection requirements.

[0114] The embodiment of the present invention proposes a heat dissipation improvement design system for a protection tube. The environmental load data is obtained as basic data through a data acquisition module, and the temperature field data, fluid field data and stress field data are fully considered. Then, the coupling effect of multiple physical fields is analyzed through a model construction module, a temperature distribution feature acquisition module and a stress distribution feature acquisition module. The fluid data outside the protection tube can be introduced into the tube while ensuring that the protection tube has sufficient structural strength, which greatly improves the operating environment of the submarine cable in the tube and thus prevents the overheating problem of the protection tube section. Finally, the heat dissipation design of the protection tube is evaluated and analyzed by the temperature distribution characteristics of the protection tube under different environments and the stress distribution characteristics of the protection tube under different load combination conditions through a design evaluation module and a result screening module. By analyzing the overall performance of the protection tube under different heat dissipation improvement design schemes of the protection tube, the optimal heat dissipation improvement design scheme of the protection tube that meets the transmission capacity requirement of the submarine cable system is finally determined, so that the heat dissipation design of the protection tube is evaluated in multiple dimensions such as temperature and stress, thereby improving the protection effect of the protection tube.

[0115] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

[0116] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0117] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

Claims

1. A method for improving heat dissipation design of a protection tube, characterized in that: include: Based on the historical protection pipe operation database, environmental load data is obtained; wherein the environmental load data includes: temperature field data, fluid field data and stress field data; Based on the environmental load data, construct a multi-physics field coupling simulation model; Based on the temperature field data, the fluid field data and the multi-physics field coupling simulation model, obtaining temperature distribution characteristics of the protection tube under different environments; Based on the preset superposition algorithm, the stress field data and the multi-physics field coupling simulation model, the stress distribution characteristics of the protective pipe under different load combination conditions are obtained; Based on the temperature distribution characteristics of the protection tube under the different environments and the stress distribution characteristics of the protection tube under different load combination conditions, several different protection tube heat dissipation improvement design schemes and protection tube structural strength assessment results are obtained; Based on the protection tube structural strength assessment result, several different protection tube heat dissipation improvement design solutions are screened to obtain protection tube heat dissipation improvement design results that meet preset protection requirements.

2. A heat dissipation improvement design method for a protection tube as claimed in claim 1, characterized in that: Based on the environmental load data, a multi-physics field coupling simulation model is constructed, specifically: Based on the design parameters of the protection tube, a geometric model of the protection tube is constructed; Based on the protection tube geometric model, the material properties of each layer structure setting of the protection tube geometric model are obtained through simulation model analysis; Based on the environmental load data, the temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions are set respectively; wherein the temperature field boundary conditions include: the setting of heat source, convection heat dissipation coefficient, solar radiation intensity and ambient temperature; the fluid field boundary conditions include: the setting of flow velocity and pressure; the stress field boundary conditions include: the setting of wind load, wave load, ocean current load and gravity load; Based on the layer structures of the protective tube geometric model, material properties, temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions are set to construct a multi-physics field coupling simulation model.

3. A heat dissipation improvement design method for a protection tube as claimed in claim 1, characterized in that: Based on the temperature field data, the fluid field data and the multi-physics field coupling simulation model, the temperature distribution characteristics of the protection tube under different environments are obtained, specifically: Inputting the temperature field data and the fluid field data into the multi-physics field coupling simulation model respectively to calculate the temperature distribution data of the protection tube; Based on the protection tube temperature distribution data, protection tube temperature distribution characteristics under different environments are constructed.

4. A heat dissipation improvement design method for a protection tube as claimed in claim 1, characterized in that: Based on the preset superposition algorithm, the stress field data and the multi-physics field coupling simulation model, the stress distribution characteristics of the protective pipe under different load combination conditions are obtained, specifically: Based on the preset superposition algorithm, several superposition results are obtained by superimposing the maximum value of the load in the rotation stress field data with the load value of the residual stress field data; Based on the several superposition results, construct a load combination condition; The load combination working condition is input into the multi-physics field coupling simulation model to obtain the stress distribution characteristics of the protective pipe under different load combination working conditions.

5. A heat dissipation improvement design method for a protection tube as claimed in claim 4, characterized in that: Based on the preset superposition algorithm, the maximum value of the load in the rotation stress field data is superimposed with the load value of the residual stress field data to obtain several superposition results, specifically: Based on the stress field data, the maximum value of each load is obtained; The maximum values ​​of each load and their corresponding residual stress field data load values ​​are superimposed by the Turkstra superposition algorithm to obtain several superposition results; wherein the residual stress field data load value is specifically: in one superposition operation, the value of all remaining loads obtained by eliminating the load whose maximum value is read in rotation.

6. A heat dissipation improvement design method for a protection tube as claimed in claim 4 or 5, characterized in that: Also includes: Obtain the mass matrix, damping matrix and stiffness matrix of the protection pipe structure; Based on the first-order natural frequency and second-order natural frequency of the protection tube structure, the mass damping coefficient and stiffness damping coefficient are calculated; Constructing a Rayleigh damping coefficient based on the mass matrix, the damping matrix stiffness matrix, the mass damping coefficient and the stiffness damping coefficient; Based on the Rayleigh damping coefficient, the load combination working condition is input into the multi-physics field coupling simulation model to obtain the stress distribution characteristics of the protection pipe under different load combination working conditions.

7. A heat dissipation improvement design method for a protection tube as claimed in claim 1, characterized in that: Based on the temperature distribution characteristics of the protection tube under the different environments and the stress distribution characteristics of the protection tube under different load combination conditions, several different protection tube heat dissipation improvement design schemes and protection tube structural strength assessment results are obtained, specifically: Based on the temperature distribution characteristics of the protection tube under the different environments, the key focus areas of the protection tube heat dissipation improvement design are obtained; By analyzing the key areas of the heat dissipation improvement design of the protection tube, several different heat dissipation improvement design schemes for the protection tube are obtained; Based on the stress distribution characteristics of the protection pipe under the different load combination working conditions, the yield failure damage of the protection pipe is judged to obtain the structural strength assessment result of the protection pipe.

8. A heat dissipation improvement design method for a protection tube as claimed in claim 1, characterized in that: Based on the protection tube structural strength assessment result, several different protection tube heat dissipation improvement design schemes are screened to obtain the protection tube heat dissipation improvement design results that meet the preset protection requirements, specifically: Based on the protection tube structural strength assessment result, the several different protection tube heat dissipation improvement design schemes are verified to obtain the structural strength verification results of the several different protection tube heat dissipation improvement design schemes; By screening the structural strength verification results of the several different protection tube heat dissipation improvement design schemes, the protection tube heat dissipation improvement design result that meets the load increase demand and has the highest structural safety margin is obtained.

9. A heat dissipation improvement design system for a protection tube, characterized in that: include: Data acquisition module, model building module, temperature distribution feature acquisition module, stress distribution feature acquisition module, design evaluation module and result screening module; The data acquisition module is used to acquire environmental load data based on the historical protection pipe operation database; wherein the environmental load data includes: temperature field data, fluid field data and stress field data; The model building module is used to build a multi-physics field coupling simulation model based on the environmental load data; The temperature distribution feature acquisition module is used to acquire the temperature distribution features of the protection tube under different environments based on the temperature field data, the fluid field data and the multi-physics field coupling simulation model; The stress distribution feature acquisition module is used to acquire the stress distribution features of the protection pipe under different load combination conditions based on a preset superposition algorithm, the stress field data and the multi-physical field coupling simulation model; The design evaluation module is used to obtain several different heat dissipation improvement design schemes for the protection tube and the protection tube structural strength evaluation results based on the temperature distribution characteristics of the protection tube under the different environments and the stress distribution characteristics of the protection tube under different load combination working conditions; The result screening module is used to screen the several different protection tube heat dissipation improvement design schemes based on the protection tube structural strength evaluation result, and obtain the protection tube heat dissipation improvement design result that meets the preset protection requirements.

10. The heat dissipation improvement design system of the protection tube according to claim 9, characterized in that: The model building module is used to build a multi-physics field coupling simulation model based on the environmental load data, and also includes: A geometric model building unit, a property analysis unit, a condition setting unit and a simulation model building unit; The geometric model building unit is used to build a geometric model of the protection tube based on the design parameters of the protection tube; The property analysis unit is used to obtain the material properties of each layer structure setting of the protection tube geometric model through simulation model analysis based on the protection tube geometric model; The condition setting unit is used to set the temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions respectively based on the environmental load data; wherein the temperature field boundary conditions include: the setting of heat source, convection heat dissipation coefficient, solar radiation intensity and ambient temperature; the fluid field boundary conditions include: Setting of flow velocity and pressure; the stress field boundary conditions include: setting of wind load, wave load, ocean current load and gravity load; The simulation model building unit is used to set material properties, temperature field boundary conditions, fluid field boundary conditions and stress field boundary conditions based on each layer structure of the protection tube geometric model to build a multi-physical field coupling simulation model.

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