A method and system for analyzing heat transfer difference of continuous casting based on diffusion-convection coupling

Abstract

The application relates to the technical field of copper rod continuous casting, in particular to a continuous casting heat transfer difference analysis method and system based on diffusion convection coupling, which comprises the following steps: a multi-physical field coupling model is constructed, the multi-physical field coupling model establishes a heat transfer process according to the coupling interaction of diffusion and convection effects; the boundary conditions corresponding to the multi-physical field coupling model are set; the multi-physical field coupling model is discretized and numerically solved to obtain the field distribution of each physical field based on the coupling interaction; the interaction of the diffusion and convection effects at continuous space-time positions is analyzed according to the field distribution to obtain continuous casting heat transfer difference analysis results. Through the application, the problem of heat transfer difference in the continuous casting process is effectively solved, in particular the problem of temperature non-uniformity and heat transfer difference caused by the coupling of diffusion and convection effects.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of continuous casting of copper rods, and particularly relates to a continuous casting heat transfer difference analysis method and system based on diffusion-convection coupling. BACKGROUND

[0002] The continuous casting process is a key step in the metal smelting process that solidifies liquid metal into solid metal, and its quality directly affects the performance of the final product. During the process of metal liquid changing from liquid to solid, due to the mutual influence of temperature field and flow field, the heat transfer process is usually controlled by diffusion effect and convection effect, and the two effects present complex coupling interaction in different continuous casting areas.

[0003] The traditional heat conduction analysis method usually divides the heat transfer process into two parts, heat diffusion and convection, and processes them separately. However, this traditional method cannot accurately capture the non-uniformity of the heat transfer process of the metal liquid under the action of different cooling rates, flow rates and temperature distributions, especially in the continuous casting process, resulting in too large temperature gradient or uneven heat transfer, which leads to problems such as surface defects or internal cracks of the cast blank.

[0004] The information disclosed in this BACKGROUND section is only intended to enhance the understanding of the general background of the present disclosure and should not be taken as an acknowledgment or any form of suggestion that this information constitutes prior art in the field. SUMMARY

[0005] The present application provides a continuous casting heat transfer difference analysis method and system based on diffusion-convection coupling, which can effectively solve the problems in the background art.

[0006] In order to achieve the above purpose, the technical solution adopted by the present application is:

[0007] A continuous casting heat transfer difference analysis method based on diffusion-convection coupling, the method comprising:

[0008] Constructing a multi-physics field coupling model, the multi-physics field coupling model establishing a heat transfer process according to the coupling interaction of diffusion and convection effects;

[0009] Setting the boundary conditions corresponding to the multi-physics field coupling model;

[0010] Discretizing and numerically solving the multi-physics field coupling model to obtain the field distribution of each physical field based on the coupling interaction;

[0011] According to the field distribution, the interaction of the diffusion and convection effects at continuous space-time positions is analyzed to obtain the continuous casting heat transfer difference analysis result.

[0012] Further, discretizing and numerically solving the multi-physics coupling model, comprising:

[0013] Discretizing the temperature field and the flow velocity field of each continuous casting region in space by grid division, converting the continuous physical field into a finite number of discrete grid nodes;

[0014] Numerically solving the coupling effect of heat transfer of the temperature field and fluid flow of the flow velocity field on each discrete grid node;

[0015] In the numerical solving process, the distribution of the temperature field and the flow velocity field on each discrete grid node is optimized by an iterative solving method;

[0016] According to the iterative solving result, analyzing the change of the temperature field and the flow velocity field of each continuous casting region, quantifying the interaction of the diffusion and convection effect in continuous time and space position.

[0017] Further, quantifying the interaction of the diffusion and convection effect in continuous time and space position, comprising:

[0018] Obtaining the change rate of the temperature field and the flow velocity field of each discrete grid node;

[0019] Based on the iterative solving result, the coupling strength of the diffusion and convection effect is obtained by simulating the change rate of the temperature field and the flow velocity field;

[0020] According to the change of the coupling strength, identifying the potential temperature abnormal region, and determining the coupling influence range of the diffusion and convection effect according to the temperature abnormal region;

[0021] Based on the coupling influence range, determining the interaction of the diffusion and convection effect in continuous time and space position.

[0022] Further, obtaining the temperature field distribution, comprising:

[0023] Obtaining the continuous casting heat source term according to the temperature gradient and the external heat source power;

[0024] Setting the heat loss term based on the heat exchange mechanism and the physical properties of the metal;

[0025] Taking the continuous casting heat source term and the heat loss term as input parameters, and establishing a fluid dynamics model based on the heat exchange mechanism;

[0026] Based on the influence of the continuous casting heat source term and the heat loss term on the temperature distribution, simulating the heat transfer process according to the fluid dynamics model, and obtaining the temperature field distribution.

[0027] Further, simulating the heat transfer process, comprising:

[0028] solving a diffusion equation and a convection equation and obtaining a coupling equation based on the hydrodynamic model, the diffusion equation describing a conductive diffusion process of heat, the convection equation describing a convective transfer process of heat;

[0029] discretizing the coupling equation by using a numerical method;

[0030] introducing the heat source term and the heat loss term as a calculation coefficient in the coupling equation, and discretely and iteratively solving a gradient value of the temperature gradient;

[0031] based on the size of the gradient value, simulating the heat transfer process according to the hydrodynamic model.

[0032] Further, analyzing the influence of the diffusion and convection effects on thermal non-uniformity and heat transfer behavior, including:

[0033] obtaining a temperature gradient and a heat flux density of each continuous casting area;

[0034] obtaining an action intensity value of the temperature gradient based on the diffusion and convection effects in each continuous casting area;

[0035] based on the heat flux density of each continuous casting area, simulating a heat flux density path, and obtaining a potential heat transfer difference according to an abnormal value existing in the heat flux density path;

[0036] analyzing thermal non-uniformity and heat transfer difference in the continuous casting process according to the action intensity value and the potential heat transfer difference.

[0037] Further, obtaining a potential heat transfer difference, including:

[0038] collecting an instantaneous heat flux density and an instantaneous temperature gradient of each continuous casting area at a time node;

[0039] obtaining a dynamic change range of the heat transfer difference in different continuous casting areas based on the diffusion and convection effects according to a difference between each of the instantaneous heat flux density and the instantaneous temperature gradient;

[0040] quantifying a time dependence of the heat transfer difference of each continuous casting area based on the diffusion and convection effects according to the time node;

[0041] comparing historical heat information to obtain the potential heat transfer difference according to the dynamic change range and the time dependence of each continuous casting area.

[0042] Further, setting a boundary condition corresponding to the multi-physical field coupling model, including:

[0043] setting a temperature boundary condition according to an actual operation condition of a process, the temperature boundary condition including an initial temperature, a surface temperature, and a temperature distribution of a phase change region;

[0044] The fluid dynamic property boundary conditions are set according to fluid flow characteristics, and the fluid dynamic property boundary conditions include fluid velocity, a turbulent flow model, and thermal physical parameters of the fluid.

[0045] A continuous casting heat transfer difference analysis system based on diffusion-convection coupling, the system comprises:

[0046] A model construction module constructs a multi-physics field coupling model, and the multi-physics field coupling model establishes a heat transfer process according to the coupling interaction of diffusion and convection effects.

[0047] A boundary limiting module sets boundary conditions corresponding to the multi-physics field coupling model.

[0048] A discrete mathematics module discretizes and numerically solves the multi-physics field coupling model to obtain field distribution of each physical field based on the coupling interaction.

[0049] A difference analysis module analyzes the interaction of diffusion and convection effects at continuous space-time positions according to the field distribution to obtain continuous casting heat transfer difference analysis results.

[0050] Further, the discrete mathematics module comprises:

[0051] A spatial discretization unit spatially discretizes the temperature field and the flow velocity field of each continuous casting area through grid division, and converts the continuous physical field into a finite number of discrete grid nodes.

[0052] A numerical solution unit numerically solves the coupling effect of heat transfer of the temperature field and fluid flow of the flow velocity field at each discrete grid node.

[0053] An iterative optimization unit optimizes the distribution of the temperature field and the flow velocity field at each discrete grid node through an iterative solution method during the numerical solution process.

[0054] An effect quantification unit analyzes the changes of the temperature field and the flow velocity field of each continuous casting area according to the iterative solution result, and quantifies the interaction of diffusion and convection effects at continuous time and space positions.

[0055] The technical scheme of the present application can achieve the following technical effects:

[0056] By simulating the changes of the temperature field and the flow velocity field during the continuous casting process, the problem of heat transfer difference caused by the coupling of diffusion and convection effects, which cannot be considered comprehensively by traditional methods, is solved. Through numerical solution and field distribution analysis, the heat transfer difference at different time and space positions is quantified, the production defects caused by temperature non-uniformity are reduced, and the stability of the continuous casting process is improved.

[0057] The above description is only a summary of the technical solutions of the present application. In order to make the technical means of the present application more clearly understood and implemented according to the content of the description, and in order to make the above and other purposes, characteristics and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0058] 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 needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments described in the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0059] Figure 1 Flow chart of the method for analyzing the heat transfer difference of continuous casting based on diffusion-convection coupling;

[0060] Figure 2 Flow chart of discretization and numerical solution of multi-physical field coupling model;

[0061] Figure 3 Structural diagram for obtaining temperature field distribution;

[0062] Figure 4 Flow chart for analyzing the influence of diffusion and convection effect on thermal non-uniformity and heat transfer behavior. DETAILED DESCRIPTION

[0063] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments.

[0064] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0065] Embodiment one;

[0066] As Figure 1 shown, the present application provides a method for analyzing the heat transfer difference of continuous casting based on diffusion-convection coupling, the method comprising:

[0067] S10: constructing a multi-physical field coupling model, the multi-physical field coupling model establishes a heat transfer process according to the coupling interaction of diffusion and convection effect;

[0068] S20: Set the boundary conditions corresponding to the multi-physical field coupling model;

[0069] S30: Discretize and numerically solve the multi-physical field coupling model to obtain the field distribution of each physical field based on the coupling interaction;

[0070] S40: According to the field distribution, analyze the interaction of diffusion and convection effect in continuous space-time position, and obtain the continuous casting heat transfer difference analysis result.

[0071] Specifically, a multi-physical field coupling model is established to describe the heat transfer process in continuous casting by considering the coupling interaction of diffusion effect and convection effect, the multi-physical field coupling model should include metal liquid flow (flow field) and temperature change (temperature field), and the coupling between the physical fields needs to be described, in order to accurately simulate the heat transfer process, fluid dynamics equation and heat conduction equation can be used to describe these effects; after establishing the multi-physical field coupling model, appropriate boundary conditions are set to ensure that the model can correctly reflect the actual continuous casting process, the boundary conditions include temperature boundary conditions (such as initial temperature, surface temperature, temperature distribution of phase change region, etc.) and fluid dynamic characteristics boundary conditions (such as fluid velocity, turbulence model and thermal physical parameters of fluid, etc.); the constructed multi-physical field coupling model is discretized in space and time, and the continuous physical field is converted into a finite number of discrete grid nodes, the temperature field and flow field of the continuous casting area are discretized in space by grid division, and the coupling effect of heat transfer and fluid flow on each grid node is solved by numerical method; according to the field distribution obtained by numerical solving, the interaction of diffusion and convection effect in continuous space-time position is further analyzed, specifically, by analyzing the change of temperature field and flow field, the interaction intensity of diffusion effect and convection effect in different time and space position can be quantified, so as to identify the difference and potential problem in heat transfer process; through the analysis of coupling effect, the continuous casting heat transfer difference analysis result in the process is obtained, according to the continuous casting heat transfer difference analysis result, the cooling strategy in continuous casting process is optimized, the process parameters are improved, the heat transfer efficiency is improved, and the production defects are reduced.

[0072] Through the technical scheme of the present application, by simulating the change of temperature field and flow field in continuous casting process, the problem of heat transfer difference caused by the coupling of diffusion and convection effect which cannot be considered comprehensively by traditional method is solved, by numerical solving and field distribution analysis, the heat transfer difference in different time and space position is quantified, the production defects caused by temperature non-uniformity are reduced, and the stability of continuous casting process is improved.

[0073] Further, as shown in Figure 2 , the discretization and numerical solution of the multi-physical field coupling model include:

[0074] The temperature field and the flow velocity field of each continuous casting region are discretized in space by grid division, and the continuous physical field is converted into a finite number of discrete grid nodes;

[0075] The coupling effect of heat transfer of the temperature field and fluid flow of the flow velocity field on each discrete grid node is numerically solved;

[0076] In the numerical solution process, the distribution of the temperature field and the flow velocity field on each discrete grid node is optimized by an iterative solution method;

[0077] According to the iterative solution result, the change of the temperature field and the flow velocity field of each continuous casting region is analyzed, and the interaction of the diffusion and convection effect in continuous time and space position is quantified.

[0078] As a preferred embodiment of the above, after the multi-physical field coupling model is constructed, the temperature field and flow velocity field of the continuous casting area are spatially discretized through grid division, the continuous casting area is divided into a plurality of small calculation units (grid units), and the continuous physical fields (such as temperature field and flow velocity field) are converted into a finite number of discrete grid nodes. In the grid division, the geometry of the continuous casting process, the fluid flow characteristics and the change of the temperature distribution should be considered to ensure that the discretized model can accurately reflect the actual situation; on each discrete grid node, the numerical solution method is used to calculate the coupling effect of the heat transfer of the temperature field and the fluid flow of the flow velocity field, and by solving the heat conduction equation and the fluid dynamics equation, the coupling of diffusion and convection effect is obtained. The change of temperature and flow velocity at each grid node can be obtained by using numerical methods such as finite difference method, finite element method or finite volume method; in the numerical solution process, the distribution of temperature field and flow velocity field at each discrete grid node is continuously optimized by iterative solution method, and the iterative process can use common solution methods such as Jacobi iteration method, conjugate gradient method or Gauss-Seidel iteration method, and the distribution of temperature and flow velocity is gradually converged. The distribution of temperature and flow velocity is adjusted according to the results of the previous step in each iteration until the system converges to the results that meet the accuracy requirements; by analyzing the changes of temperature field and flow velocity field in each continuous casting area through the iterative solution results, the change trend of temperature and flow velocity in each area can be displayed through visualization means (such as temperature distribution diagram, flow velocity distribution diagram, etc.), and the interaction of diffusion effect and convection effect in different areas and different time nodes is analyzed. By quantifying these changes, the coupling strength of diffusion and convection effect in each space-time position can be identified; according to the change of temperature field and flow velocity field, the interaction of diffusion and convection effect in continuous time and space position is further quantified, which is realized by calculating the change rate of temperature field and flow velocity field (such as temperature gradient, flow velocity gradient, etc.), and then the strength and influence range of coupling effect are identified. For example, the coupling effect in the heat transfer process can be analyzed by calculating the rate of temperature change and the rate of flow velocity change at each grid node; based on the iterative results and the analysis of coupling effect, the heat transfer and flow behavior in the continuous casting process are optimized, and the interaction of diffusion and convection effect in each space-time position is quantified, which can help to analyze and identify potential temperature abnormal areas or heat transfer differences.

[0079] Further, quantifying the interaction of diffusion and convection effect in continuous time and space position includes:

[0080] Obtaining the change rate of temperature field and flow velocity field of each discrete grid node;

[0081] Based on the iterative solution results, the coupling strength of diffusion and convection effect is obtained by simulating the change rate of temperature field and flow velocity field;

[0082] According to the change of the coupling strength, a potential temperature anomaly area is identified, and according to the temperature anomaly area, a coupling influence range of the diffusion and convection effects is determined;

[0083] Based on the coupling influence range, the interaction of the diffusion and convection effects at continuous time and space positions is determined.

[0084] As a preferred embodiment of the above-mentioned embodiment, in the numerical solution process, the temperature change rate and the flow velocity change rate of each node are obtained by calculating the change rates of the temperature field and the flow velocity field at the discrete grid nodes, based on the calculation results of each round in the iterative solution process, the temperature and flow velocity differences between adjacent grid nodes are calculated, and the change rates of the temperature field and the flow velocity field are calculated according to these differences, which can be calculated by finite difference method or similar numerical method; based on the change rates of the temperature field and the flow velocity field, the coupling strength of the diffusion and convection effects is further simulated, first, the correlation between the change rates of the temperature field and the flow velocity field is calculated, such as the product of the change rates of the temperature field and the flow velocity field or other correlation functions, according to the change rates, the basic principles of fluid mechanics and heat conduction are combined to simulate the coupling strength, the coupling strength can be quantified as a numerical value representing the interaction strength between the diffusion effect and the convection effect, and different physical constants (such as thermal conductivity coefficient, fluid viscosity, etc.) can be introduced to adjust the calculation of the coupling strength; according to the calculated coupling strength change, the regions where temperature anomalies may exist are identified, the coupling strength is analyzed in space and time, and its change trend in different regions and different times is observed, by setting a threshold, the regions where the coupling strength abnormally increases are identified, these regions where the coupling strength abnormally increases may be caused by the imbalance of the interaction between diffusion and convection effects or local flow anomalies, and these abnormal regions often mean potential problems in the heat transfer process, such as local overheating or overcooling, which may cause production defects; by analyzing the potential temperature anomaly regions, the coupling influence range of diffusion and convection effects is further determined, based on the spatial distribution of the temperature anomaly regions, the relationship between the temperature anomaly regions and the flow velocity field is determined, the coupling influence range of diffusion and convection effects in the temperature anomaly regions is evaluated, for each identified abnormal region, the coupling strength in the abnormal region is analyzed, the influence range of diffusion and convection effects in the abnormal region is speculated, and how these effects evolve over time can be visualized to draw the spatial distribution of the coupling effect influence region, and further analyze the heat transfer performance of these regions; based on the coupling influence range of diffusion and convection effects, the interaction at continuous time and spatial positions is determined, according to the identified coupling influence range, the action mode of diffusion and convection effects in these regions is analyzed, and how they affect each other and the cooling process of the metal liquid is determined, through the spatio-temporal analysis of the coupling effect, the change trend of the coupling effect at different time nodes and spatial positions is predicted, the long-term influence of diffusion and convection effects on the heat transfer difference is quantified by comparing historical data, and the cooling strategy and process parameters are further optimized to improve the heat transfer control in the continuous casting process.

[0085] Further, as shown in Figure 3 the temperature field distribution is obtained, including:

[0086] The continuous casting heat source term is obtained according to the temperature gradient and the external heat source power;

[0087] setting the heat loss term based on heat exchange mechanisms and metal physical properties;

[0088] taking the continuous casting heat source term and the heat loss term as input parameters, and establishing a fluid dynamics model based on heat exchange mechanisms;

[0089] based on the influence of the continuous casting heat source term and the heat loss term on temperature distribution, simulating the heat transfer process according to the fluid dynamics model to obtain the temperature field distribution.

[0090] As a preferred embodiment of the above, based on the temperature gradient of the metal liquid in the continuous casting process, the continuous casting heat source term is calculated in combination with the external heat source power, the temperature gradient, i.e. the rate of temperature change at each position, is calculated by analyzing the temperature distribution in the continuous casting area, the external heat source power can be obtained through the power provided by the process requirements or external equipment (such as heaters, furnaces, etc.), and the heat source power of the area can also be calculated in combination with the external environmental influence (such as cooling systems), the temperature gradient and the external heat source power are combined to obtain the heat source term that affects the metal liquid, the heat source term reflects the heat input or output in the heating or cooling process; considering the heat exchange mechanisms and the physical properties of the metal, the heat loss term is set, the heat loss term is determined according to the heat exchange mechanism between the metal liquid and the external environment (such as cooling water, mold, etc.), the heat exchange mechanism can include radiation, convection, heat conduction, etc., and the heat loss term is further set according to the thermal conductivity, specific heat capacity, density and other physical properties of the metal, the setting of the heat loss term takes into account the energy exchange between the metal and the surrounding environment during the flow process, for example, the heat loss during the cooling process; according to the fluid dynamics equation, the temperature gradient, the heat source term and the heat loss term are combined to establish a heat transfer model of the continuous casting area, the heat transfer model includes: a heat conduction equation (describing the change of temperature field) and a heat convection equation (describing the heat exchange in fluid flow), the heat source term and the heat loss term are introduced into the equation as boundary conditions or calculation coefficients; based on the established fluid dynamics model, the heat transfer process is simulated, and the temperature field distribution is calculated, a suitable numerical method (such as finite element method, finite difference method or finite volume method) is used to discretize and solve the fluid dynamics model, the temperature field distribution of each area is obtained through the iterative solution process, the simulation results will show the temperature distribution in the continuous casting area, the temperature field distribution can show the temperature change of the metal liquid during the flow process, as well as the heat transfer between different areas, especially in different areas such as phase change area, cooling area and heating area, the temperature distribution will have significant differences.

[0091] Further, simulating the heat transfer process includes:

[0092] based on the fluid dynamics model, solving the diffusion equation and the convection equation to obtain the coupled equation, the diffusion equation describes the conduction diffusion process of heat, and the convection equation describes the convection transfer process of heat;

[0093] The coupling equation is discretized by using a numerical method;

[0094] A heat source term and a heat loss term are introduced into the coupling equation as calculation coefficients, and a gradient value of the temperature gradient is calculated by iteration;

[0095] Based on the gradient value, a heat transfer process is simulated according to a fluid dynamics model.

[0096] As a preferred embodiment of the above, based on the fluid dynamics model, a diffusion equation and a convection equation are solved to obtain the coupling equation, the diffusion equation describes the conduction and diffusion process of heat in the metal liquid, and the relationship between the temperature gradient and the heat flow is usually described by using the Fourier heat conduction law; the convection equation describes the convection process of heat, and reflects the interaction between the flow and the temperature of the fluid, the motion of the fluid is described by using the Navier-Stokes equation, and the heat transfer in the flow process is calculated by combining the heat convection term, the coupling equation is obtained by solving the diffusion equation and the convection equation, and the influence of heat conduction and convection is integrated, which reflects the overall heat transfer mechanism in the continuous casting process; after the coupling equation is obtained, the equation is discretized by using a numerical method, and the continuous coupling equation is converted into an algebraic equation which can be solved by discretization; in the discretized coupling equation, a heat source term and a heat loss term are introduced as calculation coefficients, the heat source term considers the influence of external heat sources (such as heating equipment, external heat sources, etc.) in the metal liquid on the temperature field, and the heat loss term considers the heat loss caused by cooling or external environment, which affects the temperature distribution of the metal liquid, the influence of external heat sources and heat loss on the heat transfer process can be accurately reflected in the calculation by introducing the heat source term and the heat loss term into the calculation coefficients of the coupling equation; the discretized coupling equation is solved by iteration to obtain the distribution of the temperature field, in each iteration, the temperature gradient (i.e. the rate of temperature change) of each node is calculated by the discretized equation, the temperature value of each discrete grid node is updated step by step by numerical iteration until the temperature distribution converges to a stable value and meets the predetermined accuracy requirement, and the calculation of the temperature gradient reflects the intensity of heat transfer between different regions, which helps to analyze the non-uniformity in the heat transfer process; based on the gradient value of the solved temperature gradient, the heat transfer process is further simulated according to the fluid dynamics model, the heat propagation process in the metal liquid is simulated according to the calculated temperature gradient, the heat transfer between different regions through convection and diffusion is simulated according to the flow characteristics of the fluid and the change of the temperature field, and the temperature distribution in the heat transfer process is displayed by numerical calculation and visualization tools.

[0097] Further, as shown in FIG. 1, the influence of the diffusion and convection effects on the thermal non-uniformity and heat transfer behavior is analyzed, including: Figure 4

[0098] ​obtaining temperature gradient and heat flux density in each continuous casting region;

[0099] obtaining the action intensity value of temperature gradient based on diffusion and convection effect in each continuous casting region;

[0100] simulating heat flux density path based on heat flux density in each continuous casting region, and obtaining potential heat transfer difference according to abnormal value existing in heat flux density path;

[0101] analyzing thermal inhomogeneity and heat transfer difference in continuous casting process according to action intensity value and potential heat transfer difference.

[0102] As a preferred embodiment of the above, the temperature gradient and heat flux density of each point in the continuous casting region are obtained by numerical simulation or experimental measurement; the temperature gradient is obtained by calculating the rate of change of the temperature field at different positions, which can be calculated by numerical methods such as finite difference method; the heat flux density is calculated according to the temperature gradient and physical properties (such as thermal conductivity) using Fourier's law, which reflects the intensity and direction of heat transfer in the liquid metal; based on the temperature gradient, the action intensity of the diffusion effect and the convection effect on the temperature gradient is further calculated, the diffusion effect is usually proportional to the temperature gradient, so the strength of the diffusion effect can be calculated by the temperature gradient value, and the strength of the diffusion effect reflects the degree of heat diffusion in the liquid metal due to temperature difference; the convection effect depends on the flow velocity field, combined with the flow velocity and temperature gradient, the influence of the convection effect on the temperature gradient can be calculated, and the convection transfer of heat flux is closely related to the interaction of fluid velocity and temperature field; the total action intensity value of the temperature gradient change in each region is obtained by combining the diffusion effect and the convection effect; after obtaining the heat flux density of each region, the heat flux density path is simulated, and potential heat transfer difference is identified according to the heat flux density path; the flow path of heat flux density in each continuous casting region is simulated by numerical calculation, and the propagation direction and speed of heat flux are analyzed; in the heat flux density path, the regions with abnormal values are identified, which usually represent uneven heat flow in the heat transfer process, which may be caused by local uneven cooling or flow instability; based on the action intensity value of diffusion and convection effect and potential heat transfer difference, the thermal inhomogeneity and heat transfer difference in the continuous casting process are analyzed, the influence of diffusion and convection effect on temperature inhomogeneity is evaluated according to the action intensity value of each continuous casting region, and the region with larger action intensity may cause larger temperature difference, thereby causing local thermal inhomogeneity; combined with the abnormal value in the heat flux density path, the region where heat transfer inhomogeneity may exist is identified, and the thermal inhomogeneity and heat transfer difference that may occur in the continuous casting process are identified by comprehensive analysis of the action intensity and potential heat transfer difference.

[0103] Further, obtaining potential heat transfer difference includes:

[0104] collecting the instantaneous heat flux density and the instantaneous temperature gradient of each continuous casting area at time nodes;

[0105] obtaining the dynamic change range of the difference in heat transfer caused by the diffusion and convection effect in different continuous casting areas based on the difference between the instantaneous heat flux density and the instantaneous temperature gradient;

[0106] quantifying the time dependence of the difference in heat transfer of each continuous casting area caused by the diffusion and convection effect based on the time nodes;

[0107] comparing the potential heat transfer difference obtained from the dynamic change range and the time dependence of each continuous casting area with historical heat information.

[0108] As a preferred embodiment of the above, in the continuous casting process, the instantaneous heat flux density and the instantaneous temperature gradient in each continuous casting area are collected at time nodes (such as each time step or fixed intervals). By monitoring the heat flux density of the continuous casting area in real time, the temperature field and flow velocity field data can be used to calculate the instantaneous heat flux density at each time node using the Fourier law or other heat transfer formulas. According to the real-time measured temperature field, the temperature gradient of each area is calculated, which reflects the spatial distribution and transmission direction of heat in the metal liquid. The instantaneous temperature gradient can be obtained by numerical difference or interpolation method. By regularly recording these instantaneous data, the heat flux density and temperature gradient distribution over time are established. Using the collected instantaneous heat flux density and temperature gradient data, the dynamic change range of the difference in heat transfer caused by diffusion and convection effect in different continuous casting areas is calculated. The heat flux density and temperature gradient in different time nodes or different areas are compared, and the differences between them are analyzed. Based on the relationship between heat flux density and temperature gradient, the strength of the difference in heat transfer caused by diffusion and convection effect in each area is calculated. For example, a larger temperature gradient may represent a stronger diffusion effect, while a high flow rate area may exhibit a stronger convection effect. According to the differences, the dynamic change range of diffusion and convection effect in different areas is obtained, revealing the non-uniformity in the heat transfer process. The heat flux density and temperature gradient differences at each time node are quantified, and the time dependence of the diffusion and convection effect on the heat transfer difference is analyzed. By comparing the changes of heat flux density and temperature gradient at different time nodes, the law of the change of the difference in heat transfer caused by diffusion and convection effect over time is evaluated. For example, if the temperature gradient of a certain area increases over time, it may indicate that the heat transfer process in that area is gradually becoming non-uniform, or the effect of diffusion and convection is gradually increasing. Quantify these information into time-dependent curves to show the trend of heat transfer difference at different time nodes. By combining historical heat information, comparing the dynamic change range and time dependence in the current continuous casting process, potential heat transfer differences are identified. The heat flux density and temperature gradient data in the current process are compared with historical data to see if there are significant changes. For example, if the heat transfer difference in some areas becomes larger and larger, it may indicate potential heat transfer non-uniformity or process abnormalities. Based on the dynamic change range and time dependence, potential factors that may cause the difference in heat transfer are identified, such as changes in the cooling system, instability of metal flow, etc. By comparing historical data, the influence range of these potential differences is analyzed, and the possible impact on continuous casting quality is predicted.

[0109] Further, the boundary conditions corresponding to the multi-physical field coupling model are set, including:

[0110] The temperature boundary conditions are set according to the actual operating conditions of the process, including the initial temperature, surface temperature, and temperature distribution of the phase change region.

[0111] The fluid dynamic characteristic boundary condition is set according to the fluid flow characteristic, and the fluid dynamic characteristic boundary condition includes fluid velocity, a turbulent flow model and thermal physical parameters of the fluid.

[0112] As a preferred embodiment of the above embodiment, the temperature boundary condition is set according to the actual operation condition of the continuous casting process, wherein the initial temperature of the metal liquid, the surface temperature of the contact area with the mold and the temperature distribution of the phase change region are included, the initial temperature is usually determined by the furnace temperature or the melting temperature of the metal liquid, the surface temperature is considered under the influence of the external cooling condition, especially the cooling water flow rate and the cooling medium temperature, and the temperature distribution of the phase change region is particularly important when the metal liquid solidifies, because the temperature of the region changes sharply and is accompanied by a large amount of latent heat release or absorption, and the corresponding temperature boundary condition needs to be set by analyzing the phase change characteristics of the metal, secondly, the fluid dynamic characteristic boundary condition is set according to the fluid flow characteristic, including the velocity field of the fluid, the turbulent flow model and the thermal physical parameters, the velocity field of the fluid plays a key role in heat transfer and temperature field distribution, and needs to be accurately set through a flow rate distribution model, for turbulent flow, a suitable turbulent flow model is used to describe the flow characteristic, and the thermal physical parameters (such as specific heat capacity, thermal conductivity, density and viscosity) of the fluid also need to be accurately set, because they directly affect heat transfer and fluid flow, finally, after the temperature and fluid dynamic characteristic boundary conditions are set, the coupling effect of the two is considered comprehensively to ensure that the temperature field and flow field of the metal liquid are effectively simulated, and the boundary conditions jointly act to ensure accurate simulation of heat transfer, fluid flow and temperature distribution.

[0113] Embodiment two;

[0114] Based on the same inventive concept as the difference analysis method for continuous casting heat transfer based on diffusion-convection coupling in the foregoing embodiment, the application also provides a continuous casting heat transfer difference analysis system based on diffusion-convection coupling, which comprises:

[0115] A model construction module constructs a multi-physical field coupling model, and the multi-physical field coupling model establishes a heat transfer process according to the coupling interaction of diffusion and convection effects;

[0116] A boundary limiting module sets boundary conditions corresponding to the multi-physical field coupling model;

[0117] A discrete mathematics module discretizes and numerically solves the multi-physical field coupling model to obtain field distributions of each physical field based on the coupling interaction;

[0118] A difference analysis module analyzes the interaction of diffusion and convection effects at continuous space-time positions according to the field distributions to obtain a continuous casting heat transfer difference analysis result.

[0119] The adjustment system in the application can effectively realize a continuous casting heat transfer difference analysis method based on diffusion convection coupling, and the technical effects are as described in the above embodiment, which will not be repeated here.

[0120] Further, the discrete mathematics module comprises:

[0121] The space discretization unit discretizes the temperature field and the flow velocity field of each continuous casting area through grid division, and converts the continuous physical field into a finite number of discrete grid nodes.

[0122] The numerical solution unit numerically solves the coupling effect of heat transfer of the temperature field and fluid flow of the flow velocity field on each discrete grid node.

[0123] The iterative optimization unit optimizes the distribution of the temperature field and the flow velocity field on each discrete grid node through an iterative solution method during the numerical solution process.

[0124] The effect quantization unit analyzes the changes of the temperature field and the flow velocity field of each continuous casting area according to the iterative solution result, and quantizes the interaction of the diffusion and convection effects at continuous time and space positions.

[0125] Similarly, the above optimization scheme of the system can also correspondingly realize the optimization effect of the method in Embodiment 1, which will not be repeated here.

[0126] Although the present application has been described in conjunction with specific features and embodiments thereof, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of the application. Accordingly, the present specification and drawings are merely illustrative of the exemplary embodiments of the present application, and are to be regarded as covering all modifications, variations, combinations or equivalents that fall within the scope of the present application. Obviously, those skilled in the art can make various modifications and changes to the present application without departing from the scope of the present application. Thus, if these modifications and changes of the present application belong to the scope of the present application and its equivalent technology, the present application is intended to include these modifications and changes.

Claims

1. A method for analyzing heat transfer difference in continuous casting based on coupling of diffusion and convection, characterized in that, The method comprises: constructing a multi-physics coupling model, which establishes a heat transfer process according to the coupling interaction of diffusion and convection effects; setting boundary conditions corresponding to the multi-physics coupling model; discretizing and numerically solving the multi-physics coupling model to obtain field distribution of each physical field based on the coupling interaction; analyzing the interaction of the diffusion and convection effects at continuous space-time positions according to the field distribution to obtain continuous casting heat transfer difference analysis results, including: obtaining temperature gradient and heat flux density of each continuous casting area; obtaining the action intensity value of the diffusion and convection effects on the temperature gradient in each continuous casting area; simulating heat flux density path based on the heat flux density of each continuous casting area, and obtaining potential heat transfer difference according to abnormal values existing in the heat flux density path; analyzing thermal inhomogeneity and heat transfer difference in the continuous casting process according to the action intensity value and the potential heat transfer difference; obtaining potential heat transfer difference, including: collecting instantaneous heat flux density and instantaneous temperature gradient of each continuous casting area at time nodes; obtaining the dynamic change range of the diffusion and convection effects on heat transfer difference in different continuous casting areas based on the difference between each instantaneous heat flux density and instantaneous temperature gradient; quantifying the time dependence of the diffusion and convection effects on the heat transfer difference of each continuous casting area based on the time nodes; comparing historical heat information to obtain the potential heat transfer difference according to the dynamic change range and the time dependence of each continuous casting area.

2. The method for analyzing heat transfer difference in continuous casting based on coupled diffusion convection according to claim 1, characterized in that, Discretizing and numerically solving the multi-physics coupling model, including: spatially discretizing the temperature field and flow velocity field of each continuous casting area through grid division, and converting continuous physical fields into a finite number of discrete grid nodes; numerically solving the coupling effect of heat transfer of the temperature field and fluid flow of the flow velocity field on each discrete grid node; optimizing the distribution of the temperature field and the flow velocity field on each discrete grid node through an iterative solving method during numerical solving; analyzing the changes of the temperature field and the flow velocity field of each continuous casting area according to the iterative solving result, and quantifying the interaction of the diffusion and convection effects at continuous time and space positions.

3. The method for analyzing heat transfer difference in continuous casting based on coupled diffusion-convection according to claim 2, characterized in that, Quantifying the interaction of the diffusion and convection effects at continuous time and space positions, including: obtaining the change rate of the temperature field and the flow velocity field of each discrete grid node; obtaining the coupling strength of the diffusion and convection effects through the change rate of the temperature field and the flow velocity field based on the iterative solving result; identifying potential temperature abnormal areas according to the change of the coupling strength, and determining the coupling influence range of the diffusion and convection effects according to the temperature abnormal areas; determining the interaction of the diffusion and convection effects at continuous time and space positions based on the coupling influence range.

4. The method for analyzing heat transfer difference in continuous casting based on coupled diffusion convection according to claim 1, characterized in that, The field distribution includes temperature field distribution, and obtaining temperature field distribution, including: obtaining continuous casting heat source terms according to temperature gradient and external heat source power; setting heat loss terms based on heat exchange mechanisms and metal physical properties; taking the continuous casting heat source terms and the heat loss terms as input parameters, and establishing a fluid dynamics model based on the heat exchange mechanisms; Based on the influence of the continuous casting heat source term and the heat loss term on the temperature distribution, heat transfer processes are simulated according to the fluid dynamics model to obtain a temperature field distribution.

5. The method for analyzing heat transfer difference in continuous casting based on coupled diffusion convection according to claim 4, characterized in that, Simulating heat transfer processes according to the fluid dynamics model comprises: Based on the fluid dynamics model, a diffusion equation describing a conductive diffusion process of heat and a convection equation describing a convective transfer process of heat are solved to obtain a coupled equation; The coupled equation is discretized using a numerical method; The heat source term and the heat loss term are introduced into the coupled equation as a calculation coefficient, and a gradient value of the temperature gradient is discretely and iteratively solved; Based on the size of the gradient value, the heat transfer processes are simulated according to the fluid dynamics model.

6. The analysis method of heat transfer difference in continuous casting based on coupled diffusive and convective flows according to claim 1, wherein, Setting the boundary conditions corresponding to the multi-physical field coupling model comprises: Setting a temperature boundary condition according to the actual operating conditions of the process, the temperature boundary condition including an initial temperature, a surface temperature, and a temperature distribution of a phase change region; Setting a fluid dynamic characteristic boundary condition according to the fluid flow characteristics, the fluid dynamic characteristic boundary condition including a fluid velocity, a turbulence model, and a thermal physical property parameter of the fluid.

7. A system for analyzing heat transfer difference in continuous casting based on diffusion-convection coupling, characterized in that, The system of claim 1 based on the diffusion-convection coupling continuous casting heat transfer difference analysis method, the system comprising: A model construction module that constructs a multi-physical field coupling model, the multi-physical field coupling model establishing a heat transfer process according to the coupling interaction of diffusion and convection effects; A boundary limiting module that sets boundary conditions corresponding to the multi-physical field coupling model; A discrete mathematics module that discretizes and numerically solves the multi-physical field coupling model to obtain field distributions of each physical field based on the coupling interaction; A difference analysis module that analyzes the interaction of diffusion and convection effects at continuous space-time positions according to the field distributions to obtain continuous casting heat transfer difference analysis results.

8. The coupled-diffusive convection-based continuous-casting heat transfer discrepancy analysis system of claim 7, wherein, The discrete mathematics module comprises: A spatial discretization unit that spatially discretizes temperature fields and flow velocity fields of each continuous casting region through grid division, and converts continuous physical fields into a finite number of discrete grid nodes; A numerical solution unit that numerically solves the coupling effects of heat transfer of the temperature field and fluid flow of the flow velocity field at each discrete grid node; An iterative optimization unit that optimizes the distribution of the temperature field and the flow velocity field at each discrete grid node through an iterative solution method in the numerical solution process; An effect quantification unit that analyzes changes in the temperature field and the flow velocity field of each continuous casting region according to the iterative solution results, and quantifies the interaction of diffusion and convection effects at continuous time and space positions.

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