Methods and Equipment for Heat Transfer Analysis of Heat Exchangers Based on Fractal Vicsek Model

Abstract

This invention provides a method and device for heat transfer analysis of heat exchangers based on a fractal Vicsek model, comprising the following steps: real-time monitoring of the heat transfer temperature distribution during the heat transfer process of the heat exchanger; preprocessing the collected heat exchanger parameters based on the fractal Vicsek model; constructing a three-dimensional heat transfer energy change model of the heat exchanger based on the preprocessed heat exchanger data; and constructing different temperature nodes T based on the constructed three-dimensional heat transfer energy change model of the heat exchanger. θ The method involves defining boundary parameter conditions under specific conditions to determine the parameter boundaries for heat exchanger heat conduction analysis. Based on these boundaries, a calculus-based simulation model for heat exchanger heat conduction analysis is constructed to analyze the heat conduction process. This method is applicable to heat conduction analysis of geometrically complex heat exchangers, significantly reducing computational load and improving analysis efficiency. Practical application has proven its high engineering value.

Description

Technical Field

[0001] This invention belongs to the field of heat exchanger heat conduction analysis technology, specifically relating to a heat exchanger heat conduction analysis method and equipment based on the fractal Vicsek model. Background Technology

[0002] Currently, with the continuous increase in energy demand and the continuous decrease in energy reserves, the contradiction between the two is becoming increasingly prominent. Improving energy efficiency and reducing energy consumption have become urgent needs for industrial enterprises. Therefore, how to reduce energy consumption and improve energy efficiency has been a topic of discussion for the past few years. Heat exchangers are widely used in refrigeration, natural gas processing, and engine cooling. Heat exchangers are indispensable heat transfer equipment in industrial production, and improving their performance can greatly improve energy efficiency. The increasing power density encountered in equipment such as engines and refrigerators has also driven the development of improved heat exchanger designs.

[0003] Compared to other types of heat exchangers, honeycomb heat exchangers are a novel and highly efficient heat transfer device. Porous heat exchangers utilize complex geometries to maximize fluid contact area. However, when the geometry of a fractal heat exchanger is extremely complex, its heat transfer analysis is impossible or difficult to visualize. Empirical thermal conductivity has been used to capture the physical processes of cooling. However, this method cannot fully represent the complex physical phenomena of this structure, and the accuracy of empirical methods is typically low. The precision of this method cannot meet the growing demand for higher accuracy. Summary of the Invention

[0004] To address the aforementioned shortcomings, this invention provides a method and apparatus for heat conduction analysis of heat exchangers based on the fractal Vicsek model. The method of this invention can be applied to heat conduction analysis problems of geometrically complex heat exchangers, significantly reducing computational load and improving analysis efficiency. Practical application has proven its high engineering value.

[0005] This invention provides the following technical solution: a heat transfer analysis method for heat exchangers based on the fractal Vicsek model, comprising the following steps:

[0006] S1: Real-time monitoring of the heat transfer temperature distribution during the heat transfer process of the heat exchanger, and preprocessing of the collected heat exchanger parameters based on the fractal Vicsek model;

[0007] S2: Construct a three-dimensional heat transfer energy change model of the heat exchanger based on the preprocessed heat exchanger data;

[0008] S3: Based on the three-dimensional heat transfer energy change model of the heat exchanger constructed in step S2, construct different temperature nodes T. θ The boundary parameter conditions under the given conditions are divided into models to determine the parameter boundaries for heat transfer analysis of the heat exchanger;

[0009] S4: Based on the parameter boundaries of the heat exchanger heat conduction analysis obtained in step S3, construct a calculus-integral heat exchanger conduction analysis simulation model to analyze the heat exchanger heat conduction process.

[0010] Furthermore, the data preprocessing in step S1 includes the following steps:

[0011] S11: Decompose the heat conduction distribution map obtained by real-time monitoring in step S1 into 9 squares using a 3×3 grid. Remove the 4 squares located at the vertices of the squares to form 4 holes. Retain the remaining 5 squares to obtain the fractal Vicsek map.

[0012] S12: Divide each of the 5 squares retained in step S11 into 8 triangles using a cross-shaped grid.

[0013] S13: Expand and fill the four peripheral squares of the five pre-fractal squares into the four holes formed in step S11, forming four subspaces s. i Each subspace consists of several points. The point cloud subspace is formed, i = 1, 2, 3, 4, j = 1, 2, ..., N. Each hole is filled by two adjacent reserved squares from the adjacent sides, thus forming a surface subdivision fractal Vicsek diagram.

[0014] S14: Construct each subspace s i The model for minimizing the fitting error of surface subdivision points is optimized by examining the Vicsek plot of the surface subdivision fractal to minimize its fitting error at the surface subdivision points.

[0015]

[0016] in, For subspace s i Several points within Fitting error when filling to form a curved surface For the j-th point in the i-th subspace The x-coordinate value, For the j-th point in the i-th subspace The ordinate value, For the j-th point in the i-th subspace The height of the surface formed by the fill. To fill the j-th point in the i-th subspace when forming a curved surface Weighting coefficients;

[0017] S15: Each subspace s constructed according to step S14 iThe model minimizes the fitting error of the surface subdivision points. A subspace matrix S, S = AB, is constructed to minimize the fitting error of the surface subdivision points, where A is the surface fitting error coefficient matrix, A = [a0 a1 a2 a3 a4 a5], A is a 1×6 matrix, and B represents the value of the j-th point in the i-th subspace. The coordinate matrix is ​​B, which is a 6×N matrix; this is then transformed into solving the surface fitting error coefficient matrix A to minimize the surface subdivision point fitting error of the Vicsek diagram.

[0018] Furthermore, when the filling forms a curved surface, the j-th point in the i-th subspace... Weighting coefficients The calculation formula is as follows:

[0019] λ represents the Euclidean distance between the q-th point and the j-th point in the i-th subspace, and λ is the weight influence coefficient of the q-th point in the i-th subspace on the j-th point.

[0020] Furthermore, the j-th point in the i-th subspace The coordinate matrix B is:

[0021]

[0022] Furthermore, the formula for solving A in step S15 is as follows: A = (BWB T ) -1 BWF, where W is the j-th point in the i-th subspace when the surface is formed by the filling. Weighting coefficients The N×4 matrix formed by the i-th subspace and the j-th point is F. Height of the surface formed by filling A 4×N matrix is ​​formed;

[0023]

[0024] Furthermore, in step S12, each square is divided into 8 triangles using a star-shaped grid. Based on the eight points of each side endpoint and midpoint of each square, an additional midpoint of the entire square is added, resulting in a total of nine points for division.

[0025] Furthermore, in step S2, the constructed three-dimensional heat transfer energy change model of the heat exchanger is as follows:

[0026]

[0027] in, The total differential of the Vicsek map of the surface subdivision fractal obtained after the preprocessing in step S1 is given in three-dimensional space, where T is the temperature node T. θ The set, T = {T1, T2, ..., T} θ , ..., T t}, θ=1,2,…,t, k(T) is the temperature stiffness function of the Vicsek plot points of the subdivision fractal, ρ(T) is the density function of the Vicsek plot points of the subdivision fractal, and C(T) is the thermal load function of the Vicsek plot points of the subdivision fractal. This represents the error value of energy change at the three-dimensional heat transfer points of the heat exchanger.

[0028] k(T)=k0(1+γ1T), where k0 is the initial point temperature stiffness and γ1 is the point temperature stiffness influence coefficient;

[0029] ρ(T)=ρ0(1+γ2T), where ρ0 is the initial point density and γ2 is the point density influence coefficient;

[0030] C(T)=C0(1+γ3T), where C0 is the initial point heat load and γ3 is the point heat load influence coefficient.

[0031] Furthermore, the boundary parameter condition partitioning model constructed in step S3 is as follows:

[0032]

[0033] Where V is the sum of the x-coordinates, y-coordinates, and height of the filled surface formed by several points in the Vicsek graph obtained after the preprocessing in step S1, and T is the volume of the three-dimensional space. ∞ Let T be the temperature nodes as the total number of temperature nodes t→∞. θ The set, s i This refers to the i-th subspace obtained during data preprocessing in step S1. This is the set of temperature nodes representing the three-dimensional heat conduction energy change of a heat exchanger at a point in the first subspace. For the j-th point in the i-th subspace The x-coordinate value, For the j-th point in the i-th subspace The ordinate value, For the j-th point in the i-th subspace The height of the surface formed by filling.

[0034] The present invention also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described heat transfer analysis method for heat exchangers based on the fractal Vicsek model.

[0035] The present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described heat transfer analysis method for heat exchangers based on the fractal Vicsek model.

[0036] The beneficial effects of this invention are as follows:

[0037] This invention first describes the fractal using a mathematical model derived from composite functions. The fractal Vicsek model is then derived, and by filling the four holes at the vertices of the squares removed during preprocessing with the remaining five squares, the pre-fractal is transformed into a structure with four subspaces s. i The corresponding curve is subdivided into a subdivided grid fractal Vicsek diagram, and then each subspace s is constructed. i Model for minimizing fitting error at subdivision points within the surface: A subspace matrix S, S = AB, is constructed to minimize the fitting error of the surface subdivision points. This transforms the problem of minimizing the fitting error of the surface subdivision points into solving the surface fitting error coefficient matrix A, thereby minimizing the fitting error of the surface subdivision points of the Vicsek diagram and improving the accuracy and precision of subsequent calculations of the three-dimensional heat transfer energy changes of the heat exchanger.

[0038] When solving for the surface fitting error coefficient matrix A, the j-th point of the i-th subspace is constructed when the surface is filled. Weighting coefficients The j-th original point in the i-th subspace Neighboring points: The Euclidean distance from the q-th point in the i-th subspace is used as a calculation parameter. The weighting coefficients of the neighboring points around the j-th original point in the i-th subspace on the data of the Vicsek plot of the surface subdivision fractal are fully considered, which can improve the accuracy of fitting error calculation.

[0039] The heat exchanger heat transfer analysis method based on the Vicsek model provided by this invention preprocesses the data based on the fractal principle of the Vicsek model, and then utilizes the constructed three-dimensional heat transfer energy change model of the heat exchanger. Construct different temperature nodes T θThe boundary parameter condition partitioning model integrates the three-dimensional heat conduction energy change of points in each subspace of the Vicsek diagram of the surface subdivision fractal. This allows for the determination of the parameter boundaries of the heat exchanger analysis using a sufficient number of samples, after excluding useless and noisy information parameters from the heat conduction temperature distribution diagram. The three-dimensional heat conduction energy change model fully considers the influence functions k(T) of point temperature stiffness, ρ(T) of point density, and C(T) of point heat load on the heat conduction energy change obtained from the preprocessed Vicsek diagram of the surface subdivision fractal. This provides a more comprehensive and three-dimensional consideration and reflection of the influencing factors of the three-dimensional heat conduction energy change of the heat exchanger, thereby enabling more accurate determination of the boundary parameters of the three-dimensional heat conduction energy change of the heat exchanger.

[0040] The heat transfer analysis method for heat exchangers based on the Vicsek model provided by this invention, after considering the point density function, point temperature stiffness function, and point heat load function, determines the boundary parameter condition transformation model. This model then uses the sum of the three-dimensional volume V formed by the abscissa and ordinate of several points in the Vicsek diagram obtained after preprocessing in step S1, along with the height of the filled surface, and multiple subspaces s. i Differentiating from the first subspace and the second subspace respectively, we can obtain the derivative from each subspace s. i By subdividing the boundary parameters from multiple perspectives, such as the sum of volumes in three-dimensional space and each subspace, the influence of boundary parameters on the heat conduction analysis of each subspace and the Vicsek diagram of the entire surface subdivision fractal formed after data preprocessing is comprehensively and three-dimensionally considered, making the boundary parameter conditions more referential and adaptable to data fusion.

[0041] The model is imported into finite element analysis software, and numerical simulation is performed after determining parameters such as boundary conditions and initial conditions to obtain the heat transfer results. The method of this invention can be applied to heat transfer analysis problems of geometrically complex heat exchangers, greatly reducing the computational load and improving analysis efficiency. Practical experience has proven its high engineering application value. Attached Figure Description

[0042] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0043] Figure 1 A schematic diagram of the heat transfer analysis method for heat exchangers based on the fractal Vicsek model provided by this invention;

[0044] Figure 2 The fractal Vicsek diagram is obtained by step S11 of the present invention, which preprocesses the heat conduction temperature distribution diagram during the heat conduction process of the heat exchanger.

[0045] Figure 3 This is the surface subdivision fractal Vicsek diagram formed by step S13 of the present invention, which preprocesses the heat conduction temperature distribution diagram during the heat conduction process of the heat exchanger.

[0046] Figure 4 To replace the corresponding subdivided grid for heat conduction analysis of temperature distribution;

[0047] Figure 5 This is a schematic diagram of the electronic device structure for implementing the heat conduction analysis method for heat exchangers based on the fractal Vicsek model, as provided by the present invention. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] like Figure 1 The diagram shown is a flowchart of the heat transfer analysis method for heat exchangers based on the fractal Vicsek model provided by this invention, including the following steps:

[0050] S1: Real-time monitoring of the heat transfer temperature distribution during the heat transfer process of the heat exchanger, and preprocessing of the collected heat exchanger parameters based on the fractal Vicsek model;

[0051] S2: Construct a three-dimensional heat transfer energy change model of the heat exchanger based on the preprocessed heat exchanger data;

[0052] S3: Based on the three-dimensional heat transfer energy change model of the heat exchanger constructed in step S2, construct different temperature nodes T. θ The boundary parameter conditions under the given conditions are divided into models to determine the parameter boundaries for heat transfer analysis of the heat exchanger;

[0053] S4: Based on the parameter boundaries of the heat exchanger heat conduction analysis obtained in step S3, construct a calculus-based heat exchanger conduction analysis simulation model to analyze the heat exchanger heat conduction process.

[0054] In a preferred embodiment of the present invention, the data preprocessing in step S1 includes the following steps:

[0055] S11: Decompose the heat conduction distribution map obtained from real-time monitoring in step S1 into 9 squares using a 3×3 grid. Remove the 4 squares located at the vertices of the squares to form 4 holes, and retain the remaining 5 squares, resulting in the following: Figure 2 The fractal Vicsek diagram shown;

[0056] S12: Divide each of the 5 squares retained in step S11 into 8 triangles using a cross-shaped grid.

[0057] S13: Expand and fill the four peripheral squares of the five pre-fractal squares into the four holes formed in step S11, forming four subspaces s. i Each subspace consists of several points. The point cloud subspace is formed by i = 1, 2, 3, 4, j = 1, 2, ..., N. Each hole is filled by two adjacent reserved squares filling the adjacent sides, thus forming a point cloud subspace. Figure 3 The Vicsek diagram showing the subdivision fractal of the surface is shown.

[0058] S14: Construct each subspace s i The model for minimizing the fitting error of surface subdivision points is optimized by examining the Vicsek plot of the surface subdivision fractal to minimize its fitting error at the surface subdivision points.

[0059]

[0060] in, For subspace s i Several points within Fitting error when filling to form a curved surface For the j-th point in the i-th subspace The x-coordinate value, For the j-th point in the i-th subspace The ordinate value, For the j-th point in the i-th subspace The height of the surface formed by the fill. To fill the j-th point in the i-th subspace when forming a curved surface Weighting coefficients;

[0061] S15: Each subspace s constructed according to step S14 i The model minimizes the fitting error of the surface subdivision points. It constructs a subspace matrix S, s = AB, to minimize the fitting error of the surface subdivision points, where A is the surface fitting error coefficient matrix, A = [a0 a1 a2 a3 a4 a5], A is a 1×6 matrix, and B represents the value of the j-th point in the i-th subspace. The coordinate matrix is ​​B, which is a 6×N matrix; this is then transformed into solving the surface fitting error coefficient matrix A to minimize the fitting error of the surface subdivision points of the Vicsek diagram.

[0062] The j-th point in the i-th subspace The coordinate matrix B is:

[0063]

[0064] When filling to form a curved surface, the j-th point of the i-th subspace Weighting coefficients The calculation formula is as follows:

[0065] λ represents the Euclidean distance from the q-th point (a neighboring point of the j-th original point) to the j-th point in the i-th subspace, and λ is the weight influence coefficient of the q-th point in the i-th subspace on the j-th point.

[0066] The formula for solving A in step S15 is as follows: A = (BWB T ) -1 BWF, where W is the j-th point in the i-th subspace when the surface is formed by filling. Weighting coefficients The N×4 matrix formed by the i-th subspace and the j-th point is F. Height of the surface formed by filling A 4×N matrix is ​​formed;

[0067]

[0068] In a preferred embodiment of the present invention, in step S12, each square is divided into 8 triangles using a cross-shaped grid. Based on the eight points of each side endpoint and midpoint of each square, an additional midpoint of the entire square is added, resulting in a total of nine points for division.

[0069] In step S2, as another preferred embodiment of the present invention, the constructed three-dimensional heat transfer energy change model of the heat exchanger is as follows:

[0070]

[0071] in, The total differential in three-dimensional space of the Vicsek plot of the surface subdivision fractal obtained after preprocessing in step S1, where T represents the temperature nodes. θ The set, T = {T1, T2, ..., T} θ , ..., T t}, θ=1,2,…,t, k(T) is the temperature stiffness function of the Vicsek plot points of the subdivision fractal, ρ(T) is the density function of the Vicsek plot points of the subdivision fractal, and C(T) is the thermal load function of the Vicsek plot points of the subdivision fractal. This represents the error value of energy change at the three-dimensional heat transfer points of the heat exchanger.

[0072] k(T)=k0(1+γ1T), where k0 is the initial point temperature stiffness and γ1 is the point temperature stiffness influence coefficient;

[0073] ρ(T)=ρ0(1+γ2T), where ρ0 is the initial point density and γ2 is the point density influence coefficient;

[0074] C(T)=C0(1+γ3T), where C0 is the initial point heat load and γ3 is the point heat load influence coefficient.

[0075] After preprocessing the data based on the fractal principle of the Vicsek model, a three-dimensional heat transfer energy change model of the heat exchanger was constructed.

[0076] Construct different temperature nodes T θ The boundary parameter condition partitioning model integrates the three-dimensional heat conduction energy change of points in each subspace of the Vicsek diagram of the surface subdivision fractal. This allows for the determination of the parameter boundaries of the heat exchanger analysis using a sufficient number of samples, after excluding useless and noisy information parameters from the heat conduction temperature distribution diagram. The three-dimensional heat conduction energy change model fully considers the influence functions k(T) of point temperature stiffness, ρ(T) of point density, and C(T) of point heat load on the heat conduction energy change obtained from the preprocessed Vicsek diagram of the surface subdivision fractal. This provides a more comprehensive and three-dimensional consideration and reflection of the influencing factors of the three-dimensional heat conduction energy change of the heat exchanger, thereby enabling more accurate determination of the boundary parameters of the three-dimensional heat conduction energy change of the heat exchanger.

[0077] The boundary parameter condition partitioning model constructed in step S3 is as follows:

[0078]

[0079] Where V is the sum of the x and y coordinates of several points in the Vicsek graph of the surface subdivision fractal obtained after the S1 step preprocessing, and the height of the filled surface, forming the volume of the three-dimensional space. ∞ Let T be the temperature nodes as the total number of temperature nodes t→∞. θ The set, s i This refers to the i-th subspace obtained during data preprocessing in step S1. This is the set of temperature nodes representing the three-dimensional heat conduction energy change of a heat exchanger at a point in the first subspace. For the j-th point in the i-th subspace The x-coordinate value, For the j-th point in the i-th subspace The ordinate value, For the j-th point in the i-th subspace The height of the surface formed by filling.

[0080] The heat transfer analysis method for heat exchangers based on the Vicsek model provided by this invention, after considering the point density function, point temperature stiffness function, and point heat load function, determines the boundary parameter condition transformation model. This model then uses the sum of the three-dimensional volume V formed by the abscissa and ordinate of several points in the Vicsek diagram obtained after preprocessing in step S1, along with the height of the filled surface, and multiple subspaces s. i Differentiating from the first subspace and the second subspace respectively, we can obtain the derivative from each subspace s. i By subdividing the boundary parameters from multiple perspectives, such as the sum of volumes in three-dimensional space and each subspace, the influence of boundary parameters on the heat conduction analysis of each subspace and the Vicsek diagram of the entire surface subdivision fractal formed after data preprocessing is comprehensively and three-dimensionally considered, making the boundary parameter conditions more referential and adaptable to data fusion.

[0081] The heat transfer analysis method based on the fractal Vicsek model provided in this invention is used to analyze the heat transfer of a honeycomb heat exchanger with a finely divided grid cross-section. It is assumed that the heat exchanger is made of 6061, Temper-T4 aluminum. It is assumed that the heat exchanger is used to cool industrial equipment, and its four boundaries are connected to the industrial equipment. The temperature of the industrial equipment is 303K; therefore, the four boundaries of the heat exchanger have a fixed temperature of 303K. Water is used as the coolant in the heat exchanger. Water flows through the orifices of the heat exchanger, and the flow rate is assumed to be 0.1 m / s. Furthermore, the water temperature is 293K. The volumetric heat flow rate of the heat exchanger is assumed to be 10 W / m³. 2 .

[0082] To ensure the loading conditions on the subdivisions are identical to those on the corresponding prefractals, the volumetric heat flux, boundary conditions, and heat transfer with water should be the same. A fixed temperature of 303 K is applied as the boundary condition on the corresponding boundaries of the subdivisions. For volumetric heat, to maintain a consistent total heat output, the equivalent volumetric heat flux of the subdivision is easily obtained as 5.56 W / m². 2 For the interaction between water and the heat exchanger, in order to ensure that the total heat exchange remains constant, the following equation must be satisfied: h f ΔTS f =h t ΔTS t .h f and h t Here, denoted by , and respectively by , where S is the contact area between the fluid and the heat exchanger. Therefore, the heat transfer coefficient corresponding to the contact area should be 316.84 W / (m²). 2 .K).

[0083] In the fifth step, the Abaqus steady-state analysis is set to steady-state heat transfer, where the interaction between the fluid and the heat exchanger wall is a surface film state. The heat exchanger mesh type is linear, and the mesh shape is triangular, the same as the numerical finite element method introduced in the fourth step. For the transient analysis, the material density and specific heat are increased, and the transient time period is set to 30000 s; the Abaqus increment size is 30 s, the maximum increment number is 1000, and the end step size is set when the temperature change is less than 0.0001 K.

[0084] like Figure 4 As shown, the minimum and maximum temperatures of the pre-fractal and subdivided meshes are the same. Observing these two figures, the temperatures of the corresponding regions are almost identical.

[0085] This invention also provides an electronic device employing the above-mentioned heat transfer analysis method based on the fractal Vicsek model heat exchanger, see [link to relevant documentation]. Figure 5 The diagram illustrates a structural schematic of an electronic device 10 suitable for implementing embodiments of the present disclosure. The electronic devices in the embodiments of the present disclosure may include, but are not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 5 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of the embodiments disclosed herein.

[0086] like Figure 5 As shown, the electronic device 10 may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 11, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 12 or a program loaded from a storage device 18 into a random access memory (RAM) 13. The RAM 13 also stores various programs and data required for the operation of the electronic device 10. The processing unit 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0087] Typically, the following devices can be connected to I / O interface 15: input devices 16 including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices 17 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 18 including, for example, magnetic tapes, hard disks, etc.; and communication devices 19. Communication device 19 allows electronic device 10 to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 5An electronic device 10 with various devices is shown, but it should be understood that it is not required to implement or have all of the devices shown. More or fewer devices may be implemented or have instead.

[0088] In particular, according to embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 19, or installed from a storage device 18, or installed from a ROM 12. When the computer program is executed by the processing device 11, it performs the functions defined in the methods of embodiments of this disclosure.

[0089] It should be noted that the computer-readable medium described in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in connection with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0090] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device.

[0091] The aforementioned computer-readable medium carries one or more programs that, when executed by the electronic device, cause the electronic device to: acquire at least two Internet Protocol (IP) addresses; send a node evaluation request to a node evaluation device, including at least two IP addresses, wherein the node evaluation device selects an IP address from the at least two IP addresses and returns it; and receive the IP address returned by the node evaluation device; wherein the acquired IP address indicates an edge node in the content delivery network.

[0092] Alternatively, the aforementioned computer-readable medium carries one or more programs that, when executed by the electronic device, cause the electronic device to: receive a node evaluation request including at least two Internet Protocol (IP) addresses; select an IP address from the at least two IP addresses; and return the selected IP address; wherein the received IP address indicates an edge node in the content delivery network.

[0093] Computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0094] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0095] The units described in the embodiments of this disclosure can be implemented in software or in hardware. The name of a unit does not necessarily limit the unit itself; for example, the first acquisition unit can also be described as "a unit that acquires at least two Internet Protocol addresses".

[0096] This invention is not limited to the specific technical solutions of the above embodiments. Besides the embodiments described above, this invention may have other implementation schemes. All technical solutions formed by equivalent substitutions are within the scope of protection claimed by this invention.

Claims

1. A heat transfer analysis method for heat exchangers based on the fractal Vicsek model, characterized in that, Includes the following steps: S1: Real-time monitoring of the heat transfer temperature distribution during the heat transfer process of the heat exchanger, and preprocessing of the collected heat exchanger parameters based on the fractal Vicsek model; S2: Construct a three-dimensional heat transfer energy change model of the heat exchanger based on the preprocessed heat exchanger data; S3: Based on the three-dimensional heat transfer energy change model of the heat exchanger constructed in step S2, construct different temperature nodes T. θ The boundary parameter conditions under the given conditions are divided into models to determine the parameter boundaries for heat transfer analysis of the heat exchanger; S4: Based on the parameter boundaries of the heat exchanger heat conduction analysis obtained in step S3, construct a calculus-integral heat exchanger conduction analysis simulation model to analyze the heat exchanger heat conduction process; The data preprocessing in step S1 includes the following steps: S11: Decompose the heat conduction distribution map obtained by real-time monitoring in step S1 into 9 squares using a 3×3 grid. Remove the 4 squares located at the vertices of the squares to form 4 holes. Retain the remaining 5 squares to obtain the fractal Vicsek map. S12: Divide each of the 5 squares retained in step S11 into 8 triangles using a cross-shaped grid. S13: Expand and fill the four peripheral squares of the five pre-fractal squares into the four holes formed in step S11, forming four subspaces s. i Each subspace consists of several points. The point cloud subspace is formed, i = 1, 2, 3, 4, j = 1, 2, ..., N. Each hole is filled by two adjacent reserved squares from the adjacent sides, thus forming a surface subdivision fractal Vicsek diagram. S14: Construct each subspace s i The model for minimizing the fitting error of surface subdivision points is optimized by examining the Vicsek plot of the surface subdivision fractal to minimize its fitting error at the surface subdivision points. in, For subspace s i Several points within Fitting error when filling to form a curved surface For the j-th point in the i-th subspace The x-coordinate value, For the j-th point in the i-th subspace The ordinate value, For the j-th point in the i-th subspace The height of the surface formed by the fill. To fill the j-th point in the i-th subspace when forming a curved surface Weighting coefficients; S15: Each subspace s constructed according to step S14 i The model minimizes the fitting error of the surface subdivision points. A subspace matrix S, S = AB, is constructed to minimize the fitting error of the surface subdivision points, where A is the surface fitting error coefficient matrix, A = [a0 a1 a2 a3 a4 α5], and A is a 1×6 matrix. B represents the value of the j-th point in the i-th subspace. The coordinate matrix is ​​B, which is a 6×N matrix; this is then transformed into solving the surface fitting error coefficient matrix A to minimize the surface subdivision point fitting error of the Vicsek diagram.

2. The heat transfer analysis method for heat exchangers based on the fractal Vicsek model according to claim 1, characterized in that, When filling to form a curved surface, the j-th point in the i-th subspace Weighting coefficients The calculation formula is as follows: λ represents the Euclidean distance between the q-th point and the j-th point in the i-th subspace, and λ is the weight influence coefficient of the q-th point in the i-th subspace on the j-th point.

3. The heat transfer analysis method for heat exchangers based on the fractal Vicsek model according to claim 1, characterized in that, The j-th point in the i-th subspace The coordinate matrix B is:

4. The heat transfer analysis method for heat exchangers based on the fractal Vicsek model according to claim 1, characterized in that, The formula for solving A in step S15 is as follows: A = (BWB T ) -1 BWF, where W is the j-th point in the i-th subspace when the surface is formed by the filling. Weighting coefficients The N×4 matrix formed by the i-th subspace and the j-th point is F. Height of the surface formed by filling A 4×N matrix is ​​formed; 5. The heat transfer analysis method for heat exchangers based on the fractal Vicsek model according to claim 1, characterized in that, In step S12, each square is divided into 8 triangles using a cross-shaped grid. Based on the eight points of each side endpoint and midpoint of each square, an additional midpoint of the entire square is added, resulting in a total of nine points for division.

6. The heat transfer analysis method for heat exchangers based on the fractal Vicsek model according to claim 1, characterized in that, In step S2, the constructed three-dimensional heat transfer energy change model of the heat exchanger is as follows: in, The total differential of the Vicsek map of the surface subdivision fractal obtained after the preprocessing in step S1 is given in three-dimensional space, where T is the temperature node T. θ A set, T = {T1, T2, ..., T} θ ,…,T t }, θ=1,2,…,t, k(T) is the temperature stiffness function of the Vicsek plot points of the subdivision fractal, ρ(T) is the density function of the Vicsek plot points of the subdivision fractal, and C(T) is the thermal load function of the Vicsek plot points of the subdivision fractal. This represents the error value of energy change at the three-dimensional heat transfer points of the heat exchanger. k(T)=k0(1+γ1T), where k0 is the initial point temperature stiffness and γ1 is the point temperature stiffness influence coefficient; ρ(T)=ρ0(1+γ2T), where ρ0 is the initial point density and γ2 is the point density influence coefficient; C(T)=C0(1+γ3T), where C0 is the initial point heat load and γ3 is the point heat load influence coefficient.

7. The heat transfer analysis method for heat exchangers based on the fractal Vicsek model according to claim 6, characterized in that, The boundary parameter condition partitioning model constructed in step S3 is as follows: Where V is the sum of the x-coordinates, y-coordinates, and height of the filled surface formed by several points in the Vicsek graph obtained after the preprocessing in step S1, and T is the volume of the three-dimensional space. ∞ Let T be the temperature nodes as the total number of temperature nodes t→∞. θ The set, s i This refers to the i-th subspace obtained during data preprocessing in step S1. This is the set of temperature nodes representing the three-dimensional heat conduction energy change of a heat exchanger at a point in the first subspace. For the j-th point in the i-th subspace The x-coordinate value, For the j-th point in the i-th subspace The ordinate value, For the j-th point in the i-th subspace The height of the surface formed by filling.

8. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the heat conduction analysis method for heat exchangers based on the fractal Vicsek model as described in any one of claims 1-7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the heat conduction analysis method for heat exchangers based on the fractal Vicsek model as described in any one of claims 1-7.

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