Optimization design method for graded porous structure of composite phase change material and related equipment
By optimizing the pore size distribution of hierarchical porous structures based on the principle of minimizing irreversible processes according to the physical laws of flow and heat transfer, the problem of performance differences in composite phase change materials is solved, and efficient and reliable material applications are realized.
Patent Information
- Application Number
- CN202511764191.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-27
- Publication Date
- 2026-03-17
AI Technical Summary
In existing technologies, the construction process of hierarchical porous structures lacks design guidelines and theoretical basis, resulting in significant performance differences in composite phase change materials, making it difficult to achieve stable performance improvement and reliable application.
By adopting the principle of minimizing irreversible processes based on the physical laws of flow and heat transfer, and by constructing physical equations and optimization functions, the pore size distribution relationship between the mother channel and the daughter channel is revealed, and the hierarchical porous structure design is optimized.
This improves the performance stability and reliability of composite phase change materials, enabling efficient material applications and overcoming efficiency and accuracy issues in traditional R&D processes.
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Abstract
Description
Technical Field
[0001] This application relates to the field of materials design technology, and in particular to a method and related equipment for optimizing the hierarchical porous structure of composite phase change materials. Background Technology
[0002] Phase change energy storage technology utilizes the latent heat of phase change materials to store and utilize thermal energy. It has advantages such as high energy density and relatively constant temperature during the storage / release process, and is considered one of the promising energy storage technologies for the future. However, single pure phase change materials usually face common key problems such as low thermal conductivity and easy leakage, which is one of the main technical difficulties that currently prevents phase change energy storage technology from being widely commercialized.
[0003] Composite phase change materials (PCMs) are constructed by encapsulating PCMs on porous carriers. The capillary action of the porous carriers confines the PCMs within the pores, preventing leakage and simultaneously enhancing thermal conductivity. The pore structure of the porous carrier material significantly impacts the encapsulation and thermal properties of the composite PCMs; therefore, optimizing the pore structure parameters of the porous carrier is a crucial method for enhancing the performance of composite PCMs.
[0004] In related technologies, the construction process of hierarchical porous structures is still based on the direct calcination and carbonization of carbon template materials followed by natural accumulation. There is a lack of corresponding design criteria and theoretical basis. The pore size structures obtained from different studies and tests do not have obvious distribution patterns and characteristics, and the performance varies significantly, making it difficult to achieve stable performance improvement and reliable application.
[0005] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention
[0006] The main objective of this application is to propose a hierarchical porous structure optimization design method and related equipment for composite phase change materials, which can stably improve the performance and reliability of composite phase change materials.
[0007] To achieve the above objectives, one aspect of this application proposes a method for optimizing the design of hierarchical porous structures in composite phase change materials, the method comprising: Obtain the material parameters of the composite phase change material; Based on the material parameters, physical equations are constructed to obtain the first physical equation based on the flow process. With minimizing the irreversible flow process as the optimization objective, the optimization function is constructed based on the first physical equation, resulting in the first optimization function; By performing an analysis of the first optimization function with respect to pore size, the first pore size distribution relationship between the mother channel and the daughter channel in the hierarchical porous structure is obtained.
[0008] In some embodiments, the method further includes: Based on the material parameters, physical equations are constructed to obtain a second physical equation based on the heat transfer process. With minimizing the irreversible heat transfer process as the optimization objective, the optimization function is constructed based on the second physical equation, resulting in the second optimization function; By performing an analysis of the second optimization function with respect to pore size, the second pore size distribution relationship between the parent channel and the child channel in the hierarchical porous structure is obtained.
[0009] In some embodiments, the material parameters are used to construct physical equations to obtain a first physical equation based on the flow process, including: Based on the material parameters, physical equations are constructed to obtain flow equations based on Poiseuille's law; The first physical equation includes the flow equation.
[0010] In some embodiments, the step of constructing physical equations based on the material parameters to obtain a second physical equation based on the heat transfer process includes: Based on the material parameters, physical equations are constructed to obtain the heat conduction equation based on Fourier's law and the convective heat transfer equation based on Newton's law of cooling. The second physical equation includes the heat conduction equation and the convective heat transfer equation.
[0011] In some embodiments, minimizing the irreversible flow process includes minimizing the pressure drop and power consumption of the flow process. The first optimization function is constructed based on the first physical equation, with minimizing the irreversible flow process as the optimization objective. This process includes: With minimizing the pressure drop during the flow process as the optimization objective, an optimization function is constructed based on the first physical equation to obtain the third optimization function; With minimizing power consumption in the flow process as the optimization objective, an optimization function is constructed based on the first physical equation to obtain the fourth optimization function; The first optimization function includes the third optimization function and the fourth optimization function.
[0012] In some embodiments, minimizing the irreversible heat transfer process includes minimizing heat dissipation in both heat conduction and heat convection processes. The optimization objective is to minimize the irreversible heat transfer process. Based on the second physical equation, an optimization function is constructed to obtain the second optimization function, which includes: With minimizing the heat dissipation during the heat conduction process as the optimization objective, the optimization function is constructed based on the second physical equation, resulting in the fifth optimization function; With minimizing the heat dissipation of the heat convection process as the optimization objective, the sixth optimization function is constructed based on the second physical equation. The second optimization function includes the fifth optimization function and the sixth optimization function.
[0013] In some embodiments, the step of performing analysis on the first optimization function with respect to pore size to obtain the first pore size distribution relationship between the parent channel and the child channel in the hierarchical porous structure includes: Conditional constraints are applied to the first optimization function to construct the Lagrange function; Taking the partial derivative of the Lagrange function with respect to the orifice diameter, we obtain the relationship between orifice diameter and flow rate. Based on the flow conservation relationship between the main channel and the sub-channel and the formula, the first distribution relationship of the orifice diameter is obtained.
[0014] In some embodiments, the step of applying conditional constraints to the first optimization function to construct a Lagrangian function includes: Using a constant fluid volume as a constraint, the constant fluid volume is multiplied by the Lagrange multiplier to obtain the constraint parameters; The constraint parameters are added to the first optimization function to obtain the Lagrange function.
[0015] To achieve the above objectives, another aspect of this application proposes a device for optimizing the hierarchical porous structure of composite phase change materials, the device comprising: The acquisition module is used to acquire the material parameters of the composite phase change material; The first construction module is used to construct physical equations based on the material parameters to obtain the first physical equations based on the flow process. The second construction module is used to construct an optimization function based on the first physical equation with the optimization objective of minimizing the irreversible flow process, and obtain the first optimization function. The analysis module is used to analyze the first optimization function with respect to the pore size, and obtain the first distribution relationship of the pore size of the mother channel and the daughter channel in the hierarchical porous structure.
[0016] To achieve the above objectives, another aspect of this application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the method described above.
[0017] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the methods described above.
[0018] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer program product, including a computer program that, when executed by a processor, implements the aforementioned method.
[0019] The embodiments of this application include at least the following beneficial effects: This application provides a method, apparatus, electronic device, storage medium, and program product for optimizing the hierarchical porous structure of composite phase change materials. This scheme constructs a first physical equation based on the flow process using material parameters; with the minimization of irreversible flow processes as the optimization objective, a first optimization function is constructed based on the first physical equation; the first optimization function is analyzed with respect to pore size to obtain the first pore size distribution relationship between the parent and child channels in the hierarchical porous structure. Based on the principle of minimizing irreversible processes in flow physics, the pore structure optimization design of the hierarchical porous carrier is performed, revealing the pore size distribution relationship between the parent and child channels in the hierarchical porous structure. This provides a theoretical basis for the precise design and efficient development of high-performance hierarchical porous composite phase change materials, which is beneficial for steadily improving the performance of composite phase change materials and realizing the reliable application of the materials. Attached Figure Description
[0020] Figure 1 This is a flowchart of the hierarchical porous structure optimization design method for composite phase change materials provided in the embodiments of this application; Figure 2 This is a schematic diagram of the hierarchical porous structure of the composite phase change material provided in the embodiments of this application; Figure 3 This is a schematic diagram of the hardware structure of the electronic device provided in the embodiments of this application. Detailed Implementation
[0021] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.
[0022] 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 this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.
[0023] Phase change energy storage technology utilizes the latent heat of phase change materials to store and utilize thermal energy. It has advantages such as high energy density and relatively constant temperature during the storage / release process, and is considered one of the promising energy storage technologies for the future. However, single pure phase change materials usually face common key problems such as low thermal conductivity and easy leakage, which is one of the main technical difficulties that currently prevents phase change energy storage technology from being widely commercialized.
[0024] Composite phase change materials (PCMs) are constructed by encapsulating PCMs on porous carriers. The capillary action of the porous carriers confines the PCMs within the pores, preventing leakage and simultaneously enhancing thermal conductivity. The pore structure of the porous carrier material significantly impacts the encapsulation and thermal properties of the composite PCMs; therefore, optimizing the pore structure parameters of the porous carrier is a crucial method for enhancing the performance of composite PCMs.
[0025] In related technologies, the construction of hierarchical porous structure carriers for the preparation of composite phase change materials can provide high load capacity while improving the molecular thermal motion and natural convection of phase change materials and enhancing heat transfer. However, the construction process of hierarchical porous structures in related technologies is still based on the direct calcination and carbonization of carbon template materials followed by natural accumulation. There is a lack of corresponding design criteria and theoretical basis. The pore size structures obtained by different studies and tests do not have obvious distribution patterns and characteristics, and the performance varies significantly, making it difficult to achieve stable performance improvement and reliable application.
[0026] In view of this, this application provides a method and related equipment for optimizing the design of hierarchical porous structures of composite phase change materials. This method optimizes the pore structure design of hierarchical porous carriers based on the principle of minimizing irreversible processes in flow physics, reveals the pore size distribution relationship between the parent and child pores in the hierarchical porous structure, provides a theoretical basis for the precise design and efficient development of high-performance hierarchical porous composite phase change materials, and is conducive to steadily improving the performance of composite phase change materials and realizing the reliable application of materials.
[0027] The hierarchical porous structure optimization design method for composite phase change materials provided in this application relates to the field of materials design technology. This method can be applied to terminals, servers, or software running on either terminal or server. In some embodiments, the terminal can be a smartphone, tablet, laptop, desktop computer, smart speaker, smartwatch, or vehicle terminal, but is not limited to these. The server can be configured as an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms. The server can also be a node server in a blockchain network. The software can be an application implementing the hierarchical porous structure optimization design method for composite phase change materials, but is not limited to the above forms.
[0028] This application can be used in a wide variety of general-purpose or special-purpose computer system environments or configurations. Examples include: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics devices, network PCs, minicomputers, mainframe computers, and distributed computing environments including any of the above systems or devices. This application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform specific tasks or implement specific abstract data types. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.
[0029] Figure 1 This is an optional flowchart of the hierarchical porous structure optimization design method for composite phase change materials provided in the embodiments of this application. Figure 1 The method may include, but is not limited to, steps S101 to S104.
[0030] Step S101: Obtain the material parameters of the composite phase change material; Step S102: Construct physical equations based on material parameters to obtain the first physical equation based on the flow process; Step S103: With minimizing the irreversible flow process as the optimization objective, an optimization function is constructed based on the first physical equation to obtain the first optimization function; Step S104: Analyze the first optimization function with respect to pore size to obtain the first pore size distribution relationship between the mother channel and the daughter channel in the hierarchical porous structure.
[0031] In steps S101 to S104 of the embodiments of this application, the hierarchical porous structure of the composite phase change material is composed of a single mother channel (i.e., macropore) connected to sub-channels (i.e., mesopores). Based on the principle of minimizing irreversible processes in flow physics, the pore structure of the hierarchical porous carrier is optimized, revealing the primary distribution relationship of pore size between the mother channel and sub-channels in the hierarchical porous structure. This provides a theoretical basis for the precise design and efficient development of high-performance hierarchical porous composite phase change materials, which is beneficial for steadily improving the performance of composite phase change materials and realizing their reliable application.
[0032] In some steps S101, please refer to Figure 2 , Figure 2 This diagram illustrates a hierarchical porous structure of a composite phase change material (PCM). In the diagram, 1 represents the mother pore (macropore), 2 represents the daughter pore (mesopore), and 3 represents the PCM within the hierarchical porous structure. Flow or heat enters through the mother pore of the PCM and exits through the daughter pore. The material parameters of the PCM may include, but are not limited to, the radius r of the hierarchical porous structure, the viscosity μ of the liquid PCM, and the length l of the hierarchical porous structure.
[0033] In some embodiments, step S102 may include, but is not limited to, step S201: Step S201: Construct physical equations based on material parameters to obtain flow equations based on Poiseuille's law.
[0034] In step S201 of some embodiments, the first physical equation based on the flow process includes a flow equation based on Poiseuille's law. Based on fluid mechanics theory, the flow equation based on Poiseuille's law is established. The flow equation based on Poiseuille's law is shown in equation (1): (1) in, Q m This refers to the liquid mass flow rate during the natural convection process after the phase change material undergoes a solid-liquid phase change. r The radius of the hierarchical porous structure of the composite phase change material is given. μ The viscosity of the liquid phase change material. l Let denoted as the length of the hierarchical porous structure of the composite phase change material, and ΔP be the pressure drop during the natural convection process of the solid-liquid phase change in the phase change material. Based on Poiseuille's law, the relationship between liquid mass flow rate and factors such as pore characteristics and pressure difference in the material parameters can be revealed, serving as the basis for constructing subsequent optimization functions.
[0035] In some embodiments, minimizing the irreversible flow process includes minimizing the pressure drop and power consumption of the flow process, and step S103 may include, but is not limited to, steps S301 to S302: Step S301: With minimizing the pressure drop in the flow process as the optimization objective, an optimization function is constructed based on the first physical equation to obtain the third optimization function; Step S302: With minimizing the power consumption of the flow process as the optimization objective, an optimization function is constructed based on the first physical equation to obtain the fourth optimization function; The first optimization function includes the third optimization function and the fourth optimization function.
[0036] In step S301 of some embodiments, based on fluid mechanics theory, an objective function for optimizing the hierarchical porous structure of the composite phase change material is established to minimize the pressure drop during the natural convection process of the solid-liquid phase change of the composite phase change material. Equation (1) is deformed to obtain Equation (2), which is the third optimization function.
[0037] (2) Wherein, ΔP represents the pressure drop during the natural convection process of the solid-liquid phase change of the composite phase change material.
[0038] In step S302 of some embodiments, based on fluid mechanics theory, an objective function for optimizing the hierarchical porous structure of the composite phase change material is established to minimize the flow power consumption during the natural convection process of the solid-liquid phase change of the composite phase change material. The objective function (fourth optimization function) for optimizing the hierarchical porous structure of the composite phase change material is shown in equation (3).
[0039] (3) Where W represents the power consumption of the flow process.
[0040] In some embodiments, step S104 may include, but is not limited to, steps S401 to S403: Step S401: Apply conditional constraints to the first optimization function and construct the Lagrange function; Step S402: Take the partial derivative of the Lagrange function with respect to the orifice diameter to obtain the relationship between orifice diameter and flow rate; Step S403: Based on the flow conservation relationship and formula of the mother channel and the daughter channel, the first distribution relationship of the orifice diameter is obtained.
[0041] In some embodiments, step S401 may include, but is not limited to, steps S411 to S412: Step S411: Using constant fluid volume as a constraint, multiply the constant fluid volume by the Lagrange multiplier to obtain the constraint parameters; Step S412: Add the constraint parameters to the first optimization function to obtain the Lagrange function.
[0042] In step S401 of some embodiments, the first optimization function includes a third optimization function and a fourth optimization function. According to the third optimization function, i.e., equation (2), the first Lagrangian function for the hierarchical porous structure optimization design of the composite phase change material is shown in equation (4).
[0043] (4) Based on fluid mechanics theory, with a constant fluid volume (πlr) 2 Using ) as constraints, the Lagrange multiplier method is used as the analytical optimization method to construct the Lagrange function for the optimal design of the hierarchical porous structure of composite phase change materials, where ) λ It is a Lagrange multiplier.
[0044] According to the fourth optimization function, i.e., equation (3), the second Lagrangian function for the hierarchical porous structure optimization design of composite phase change materials is shown in equation (5).
[0045] (5) Based on fluid mechanics theory, with a constant fluid volume, (πlr) 2 Using ) as constraints, the Lagrange multiplier method is used as the analytical optimization method to construct the Lagrange function for the optimal design of the hierarchical porous structure of composite phase change materials, where ) λ It is a Lagrange multiplier.
[0046] In step S402 of some embodiments, the partial derivative of the first Lagrange function with respect to the variable r is shown in equation (6), and the partial derivative of the second Lagrange function with respect to the variable r is shown in equation (7).
[0047] (6) (7) The problem of finding extrema under constraints is transformed into the problem of finding extrema of the Lagrange function. Finding extrema of the Lagrange function is equivalent to finding the partial derivative of the Lagrange function with respect to the variable r. The point where the derivative is equal to 0 is the extremum point.
[0048] According to equation (6), the liquid mass flow rate during the natural convection process after the material undergoes a solid-liquid phase change can be obtained. Q m With respect to the pore radius of the hierarchical porous structure r The relational expression obtained through optimized calculation Q m and r The relationship is shown in equation (8).
[0049] (8) Equation (8) indicates that when the pressure drop is minimized during natural convection, the mass flow rate through the graded porous structure is proportional to the sixth power of the pore radius.
[0050] According to equation (7), the liquid mass flow rate during the natural convection process after the phase change material undergoes a solid-liquid phase change can be obtained. Q m With respect to the pore radius of the hierarchical porous structure r The relational expression obtained through optimized calculation Q m and r The relationship is shown in equation (9).
[0051] (9) Equation (9) indicates that the mass flow rate through the pores of the hierarchical porous structure is proportional to the cube of the pore radius when using the least possible flow power.
[0052] In step S403 of some embodiments, the liquid mass flow rate during the natural convection process after the composite phase change material undergoes a solid-liquid phase change is... Q m It is leak-free, therefore the total flow rate into the main channel (i.e., the macro-orifice) is equal to the total flow rate into the sub-channels (i.e., the meso-orifice); in a single main channel (i.e., the macro-orifice) connection... n In a hierarchical porous structure with sub-channels (i.e., mesopores), the mass flow rate of liquid phase change material in the mother channel (i.e., macropores) and the sub-channels (i.e., mesopores) through natural convection satisfies the hierarchical porous flow rate relationship, that is, the flow rate conservation relationship between the mother channel and the sub-channels, as shown in equation (10).
[0053] (10) In this context, the subscripts 0 and i represent the mother channel (i.e., the macropore) and the daughter channel (i.e., the mesopore), respectively.
[0054] The first distribution relationship of the pore size of the parent channel and the child channel in the hierarchical porous structure includes a first relationship based on minimizing the pressure drop in the flow process and a second relationship based on minimizing the power consumption in the flow process.
[0055] The first relation can be obtained from equations (8) and (10), as shown in equation (11).
[0056] (11) The first relation can be obtained from equations (9) and (10), as shown in equation (12).
[0057] (12) When the pore size of all mesopores is uniformly and constantly distributed, the macropores and mesopores in the hierarchical porous structure of composite phase change materials based on Murray's law should satisfy either the first relationship or the second relationship.
[0058] In some embodiments, the hierarchical porous structure optimization design method for composite phase change materials also includes, but is not limited to, steps S105 to S107.
[0059] Step S105: Construct physical equations based on material parameters to obtain a second physical equation based on the heat transfer process; Step S106: With minimizing the irreversible heat transfer process as the optimization objective, an optimization function is constructed based on the second physical equation to obtain the second optimization function; Step S107: Analyze the second optimization function with respect to pore size to obtain the second pore size distribution relationship between the mother channel and the daughter channel in the hierarchical porous structure.
[0060] Steps S105 to S107 shown in the embodiments of this application are based on the principle of minimizing irreversible processes in the physical laws of heat transfer to carry out the pore structure optimization design of the hierarchical porous carrier, reveal the second distribution relationship of the pore size of the mother channel and the daughter channel, and optimize the material design during the heat transfer process. This can also serve as the theoretical basis for the design and development of hierarchical porous composite phase change materials.
[0061] In steps S101 to S107 of some embodiments, based on the analogy theory of biology, fluid mechanics, and heat transfer, Murray's law is extended as a design criterion to the structural design of hierarchical porous carriers, overcoming the traditional material development process of experiment-test-optimization-retest, and improving the efficiency and accuracy of composite phase change material development.
[0062] In some embodiments, step S105 may include, but is not limited to, step S501: Step S501: Construct physical equations based on material parameters to obtain heat conduction equations based on Fourier's law and convective heat transfer equations based on Newton's law of cooling. In step S501 of some embodiments, the second physical equation includes a heat conduction equation and a convective heat transfer equation. Based on the heat transfer theory, a heat conduction equation for the hierarchical porous composite phase change material based on Fourier's law is established, as shown in equation (13).
[0063] (13) in, Q ec For the heat transfer during the thermal conduction process of phase change materials, r Let be the radius of the hierarchical porous structure of the composite phase change material, and k be the thermal conductivity. lΔT represents the length of the hierarchical porous structure of the composite phase change material, and ΔT represents the temperature difference during the heat conduction process of the phase change material.
[0064] Based on the theory of heat transfer, a convective heat transfer equation for hierarchical porous composite phase change materials based on Newton's law of cooling is established, as shown in equation (14).
[0065] (14) in, Q eh For the heat transfer in the convective heat transfer process of phase change materials, r Let be the radius of the hierarchical porous structure of the composite phase change material, and h be the convective heat transfer coefficient. l ΔT represents the length of the hierarchical porous structure of the composite phase change material, and ΔT represents the temperature difference during the convective heat transfer process of the phase change material.
[0066] In some embodiments, step S106 may include, but is not limited to, steps S601 to S602: Step S601: With minimizing the heat dissipation of the heat conduction process as the optimization objective, the optimization function is constructed based on the second physical equation to obtain the fifth optimization function; Step S602: With minimizing the heat dissipation of the heat convection process as the optimization objective, the optimization function is constructed based on the second physical equation to obtain the sixth optimization function.
[0067] In step S601 of some embodiments, according to equation (13), based on the theories of heat transfer and engineering thermodynamics, an objective function (fifth optimization function) for the hierarchical porous structure optimization design of composite phase change material is established to minimize the dissipation (fire accumulation) during the heat conduction and heat transfer process of composite phase change material, as shown in equation (15).
[0068] (15) Wherein, ΔG represents the heat dissipation (fire accumulation) during the heat conduction and heat transfer process of the composite phase change material.
[0069] In step S602 of some embodiments, according to equation (14), based on the theories of heat transfer and engineering thermodynamics, an objective function (sixth optimization function) for the hierarchical porous structure optimization design of composite phase change materials is established to minimize the dissipation (fire accumulation) during the convective heat transfer process of composite phase change materials, as shown in equation (16).
[0070] (16) Wherein, ΔG represents the heat dissipation (fire accumulation) during the convective heat transfer process of the composite phase change material.
[0071] In step S107 of some embodiments, the analysis of the second optimization function with respect to the aperture is similar to step S104 described in the previous embodiments.
[0072] Based on the fifth optimization function and the theories of heat transfer and engineering thermodynamics, the constant volume (πlr) of the heat conduction and heat transfer process is considered. 2 Using ) as constraints, the Lagrangian function for the optimal design of the hierarchical porous structure of the composite phase change material is constructed using the Lagrange multiplier method as the analytical optimization method. The third Lagrangian function for the optimal design of the hierarchical porous structure of the composite phase change material is shown in Equation (17).
[0073] (17) in, λ It is a Lagrange multiplier.
[0074] The problem of finding the extremum under constraints is transformed into the problem of finding the extremum of the Lagrange function. Find the extremum of equation (17), that is, find the partial derivative of the third Lagrange function with respect to the variable r. Let the point where the derivative function is equal to 0 be the extremum point, as shown in equation (18).
[0075] (18) According to equation (18), the heat transfer Q during the thermal conduction process of the phase change material is obtained. ec The relationship between the pore radius r of the hierarchical porous structure is shown in equation (19).
[0076] (19) Equation (19) can be expressed as follows: when the heat dissipation during the heat conduction and heat transfer process (fire accumulation) is minimized, the heat transfer through the graded porous structure is proportional to the square of the pore radius.
[0077] Heat transfer during the thermal conduction process of composite phase change materials Q ec It is constant, therefore the heat transfer flowing into the main channel (i.e., the macropore) is equal to the total heat transfer flowing into all the sub-channels (i.e., the mesopores); in a single main channel (i.e., the macropore) connection n In a hierarchical porous structure with individual channels (i.e., mesopores), the heat transfer during the heat conduction process in the mother channel (i.e., macropores) and daughter channels (i.e., mesopores) is... Q e,c The heat transfer relationship of the graded porous structure is satisfied, as shown in equation (20).
[0078] (20) In this context, the subscripts 0 and i represent the mother channel (i.e., the macropore) and the daughter channel (i.e., the mesopore), respectively.
[0079] When the pore size of all mesopores is uniformly and constantly distributed, Equation (21) can be obtained according to Equations (20) and (19).
[0080] ,(twenty one) Based on Murray's law, the macropores and mesopores in the hierarchical porous structure of composite phase change materials should satisfy equation (21).
[0081] Based on the sixth optimization function, and grounded in heat transfer and engineering thermodynamics theories, the constant volume (πlr) of the convective heat transfer process is considered. 2 Using ) as constraints, the fourth Lagrangian function for the hierarchical porous structure optimization design of composite phase change materials is constructed using the Lagrange multiplier method as the analytical optimization method, as shown in equation (22).
[0082] ,(twenty two) Where λ is the Lagrange multiplier.
[0083] Take the partial derivative of the fourth Lagrange function and set the derivative function to 0, as shown in equation (23).
[0084] ,(twenty three) According to equation (23), the heat transfer rate of the convective heat transfer process can be obtained. Q ec With respect to the pore radius of the hierarchical porous structure r The relationship is shown in equation (24).
[0085] ,(twenty four) Equation (24) can be expressed as follows: when the heat dissipation of the convective heat transfer process (fire accumulation) is minimized, the heat transfer through the graded porous structure is proportional to the 1.5th power of the pore radius.
[0086] Heat transfer in the convective heat transfer process of composite phase change materials Q ec It is constant, therefore the heat transfer flowing into the main channel (i.e., the macropore) is equal to the total heat transfer flowing into all the sub-channels (i.e., the mesopores); in a single main channel (i.e., the macropore) connection n In a hierarchical porous structure with individual channels (i.e., mesopores), the heat transfer in the convective heat transfer process within the main channel (i.e., macropores) and the daughter channels (i.e., mesopores) is... Q e,c The heat transfer relationship of the graded porous structure is satisfied, as shown in equation (25).
[0087] (25) In this context, the subscripts 0 and i represent the mother channel (i.e., the macropore) and the daughter channel (i.e., the mesopore), respectively.
[0088] When the pore size of all mesopores is uniformly and constantly distributed, Equation (26) is obtained according to Equation (25) and Equation (24).
[0089] (26) Based on Murray's law, the macropores and mesopores in the hierarchical porous structure of composite phase change materials should satisfy equation (26).
[0090] The second distribution relationship of the pore size of the mother channel and the daughter channel in the hierarchical porous structure includes equations (21) and (26).
[0091] In some embodiments, a method for optimizing the design of a hierarchical porous structure of a composite phase change material includes: Based on fluid mechanics and heat transfer theory, physical equations based on flow process and heat transfer process are established after phase change material melts, including flow equation based on Poiseuille's law, heat conduction equation based on Fourier's law, and convective heat transfer equation based on Newton's cooling formula. Based on engineering thermodynamics and heat transfer theory, and taking the minimization of irreversible flow and heat transfer processes as the optimization principle, including minimizing pressure drop and power consumption in the flow process, and minimizing (fire accumulation) dissipation in the heat conduction and heat convection processes, corresponding single-objective and multi-objective functions are established. Using the Lagrange multiplier method as an analytical optimization method, the Lagrange function is established, and the functional relationship between flow rate, heat physical quantity and orifice radius is obtained by solving the problem, thus obtaining the orifice diameter distribution relationship between the main orifice and the sub-orifice.
[0092] This embodiment provides a hierarchical porous structure design optimization method for composite phase change materials based on Murray's law. The hierarchical porous carrier of the composite phase change material is composed of a mother channel and a daughter channel. The pore size distribution relationship between the mother channel and the daughter channel follows the optimization design criterion of Murray's law. By optimizing the pore structure design, the flow resistance and power consumption during the natural convection process after the phase change material melts are reduced. At the same time, the irreversibility of the heat transfer process is reduced and the heat transfer rate is improved, thereby achieving a dual improvement in the load capacity and heat transfer capacity of the composite phase change material.
[0093] This embodiment has at least the following beneficial effects: Based on analogies from biology, fluid mechanics, and heat transfer, this study innovatively extends Murray's law as a design criterion to the structural design of hierarchical porous carriers. This overcomes the traditional material development process of experimentation, testing, optimization, and retesting, significantly improving the efficiency and accuracy of composite phase change material development. Based on the principle of minimizing irreversible processes in flow and heat transfer physics, the study optimizes the pore structure of hierarchical porous carriers, directly synthesizing target materials. This enhances the stability and reliable application of composite materials, providing a theoretical basis for the precise design and efficient development of high-performance hierarchical porous composite energy storage materials.
[0094] This application embodiment also provides a device for optimizing the hierarchical porous structure design of composite phase change materials, which can implement the above method. The device includes: The acquisition module is used to acquire the material parameters of the composite phase change material; The first construction module is used to construct physical equations based on material parameters to obtain the first physical equations based on the flow process. The second construction module is used to construct the first optimization function based on the first physical equation with the goal of minimizing the irreversible flow process. The analysis module is used to analyze the first optimization function with respect to the pore size, and obtain the first distribution relationship of the pore size of the mother channel and the daughter channel in the hierarchical porous structure.
[0095] It is understood that the content of the above method embodiments is applicable to the present device embodiments. The specific functions implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.
[0096] This application also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described method. This electronic device can be any smart terminal, including tablet computers, in-vehicle computers, etc.
[0097] It is understood that the content of the above method embodiments is applicable to this device embodiment. The specific functions implemented by this device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.
[0098] Please see Figure 3 , Figure 3 The hardware structure of an electronic device according to another embodiment is illustrated. The electronic device includes: The processor 901 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this application. The memory 902 can be implemented as a read-only memory (ROM), static storage device, dynamic storage device, or random access memory (RAM). The memory 902 can store the operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 902 and is called and executed by the processor 901 using the methods described in the embodiments of this application. The input / output interface 903 is used to implement information input and output; The communication interface 904 is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.). Bus 905 transmits information between various components of the device (e.g., processor 901, memory 902, input / output interface 903, and communication interface 904); The processor 901, memory 902, input / output interface 903, and communication interface 904 are connected to each other within the device via bus 905.
[0099] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method.
[0100] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.
[0101] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.
[0102] It is understood that the content of the above method embodiments is applicable to the embodiments of this program product. The specific functions implemented by the embodiments of this program product are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.
[0103] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.
[0104] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.
[0105] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.
[0106] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.
[0107] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.
[0108] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0109] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.
[0110] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.
[0111] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0112] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.
[0113] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0114] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.
Claims
1. A method for optimizing the design of hierarchical porous structures in composite phase change materials, characterized in that, The method includes the following steps: Obtain the material parameters of the composite phase change material; Based on the material parameters, physical equations are constructed to obtain the first physical equation based on the flow process. With minimizing the irreversible flow process as the optimization objective, the optimization function is constructed based on the first physical equation, resulting in the first optimization function; By performing an analysis of the first optimization function with respect to pore size, the first pore size distribution relationship between the mother channel and the daughter channel in the hierarchical porous structure is obtained.
2. The method according to claim 1, characterized in that, The method further includes: Based on the material parameters, physical equations are constructed to obtain a second physical equation based on the heat transfer process. With minimizing the irreversible heat transfer process as the optimization objective, the optimization function is constructed based on the second physical equation, resulting in the second optimization function; By performing an analysis of the second optimization function with respect to pore size, the second pore size distribution relationship between the parent channel and the child channel in the hierarchical porous structure is obtained.
3. The method according to claim 2, characterized in that, The construction of physical equations based on the material parameters to obtain a second physical equation based on the heat transfer process includes: Based on the material parameters, physical equations are constructed to obtain the heat conduction equation based on Fourier's law and the convective heat transfer equation based on Newton's law of cooling. The second physical equation includes the heat conduction equation and the convective heat transfer equation.
4. The method according to claim 1, characterized in that, The minimization of the irreversible flow process includes minimizing the pressure drop and power consumption of the flow process. The optimization objective is to minimize the irreversible flow process. Based on the first physical equation, an optimization function is constructed to obtain the first optimization function, which includes: With minimizing the pressure drop during the flow process as the optimization objective, an optimization function is constructed based on the first physical equation to obtain the third optimization function; With minimizing power consumption in the flow process as the optimization objective, an optimization function is constructed based on the first physical equation to obtain the fourth optimization function; The first optimization function includes the third optimization function and the fourth optimization function.
5. The method according to claim 2, characterized in that, The minimization of the irreversible heat transfer process includes minimizing heat dissipation in both heat conduction and convection processes. The optimization objective is to minimize the irreversible heat transfer process. Based on the second physical equation, an optimization function is constructed to obtain the second optimization function, which includes: With minimizing the heat dissipation during the heat conduction process as the optimization objective, the optimization function is constructed based on the second physical equation, resulting in the fifth optimization function; With minimizing the heat dissipation of the heat convection process as the optimization objective, the sixth optimization function is constructed based on the second physical equation. The second optimization function includes the fifth optimization function and the sixth optimization function.
6. The method according to claim 1, characterized in that, The step of performing an analytical analysis of the first optimization function with respect to pore size to obtain the first pore size distribution relationship between the parent channel and the child channel in the hierarchical porous structure includes: Conditional constraints are applied to the first optimization function to construct the Lagrange function; Taking the partial derivative of the Lagrange function with respect to the orifice diameter, we obtain the relationship between orifice diameter and flow rate. Based on the flow conservation relationship between the main channel and the sub-channel and the formula, the first distribution relationship of the orifice diameter is obtained.
7. The method according to claim 6, characterized in that, The step of applying conditional constraints to the first optimization function to construct the Lagrange function includes: Using a constant fluid volume as a constraint, the constant fluid volume is multiplied by the Lagrange multiplier to obtain the constraint parameters; The constraint parameters are added to the first optimization function to obtain the Lagrange function.
8. A device for optimizing the hierarchical porous structure of composite phase change materials, characterized in that, The device includes: The acquisition module is used to acquire the material parameters of the composite phase change material; The first construction module is used to construct physical equations based on the material parameters to obtain the first physical equations based on the flow process. The second construction module is used to construct an optimization function based on the first physical equation with the optimization objective of minimizing the irreversible flow process, and obtain the first optimization function. The analysis module is used to analyze the first optimization function with respect to the pore size, and obtain the first distribution relationship of the pore size of the mother channel and the daughter channel in the hierarchical porous structure.
9. An electronic device, characterized in that, include: At least one processor; At least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the method as described in any one of claims 1 to 7.
10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 7.