Discrete element modeling method fusing crystal polymer particle morphology and thermal-mechanical coupling effect

Abstract

The invention belongs to the technical field related to multi-physics field coupling simulation, and discloses a discrete element modeling method fusing crystal polymer particle morphology and thermal-mechanical coupling effect, which comprises the following steps: S1, carrying out thermal-mechanical parameter experiment calibration; s2, constructing a real-form particle discrete element model; s3, obtaining a response function of the strength parameter of the crystal polymer particles along with the temperature change; s4, constructing a thermal-mechanical coupling bonding contact model; and S5, thermal-mechanical coupling behavior simulation and analysis. The method overcomes the limitation that a traditional macroscopic continuous medium model cannot reflect a real particle structure and a microscopic temperature effect, and is suitable for simulating microscopic mechanical analysis such as heat conduction characteristics, thermally induced deformation, thermal cracking and interface debonding of breakable crystal polymer particles in a high-temperature or variable-temperature environment; the single-shaft crushing process of crystal polymer particles at different temperatures is effectively simulated, the micromechanical mechanism in the process is explored, and technical support is provided for multi-field coupling research of crystal polymer compression molding and frozen soil mechanical research.

Description

Technical Field

[0001] This invention belongs to the technical field of multiphysics coupling simulation, and more specifically, relates to a discrete element modeling method that integrates the morphology of crystalline polymer particles with thermo-mechanical coupling. Background Technology Layered crystalline polymer particles are a typical type of crystalline polymer composite particle formed by using high-energy explosive crystals (such as triaminotrinitrotoluene, octogen, and tetan) as the main component, polymers such as rubber, plastics, and polyurethane as binders, and adding additives. They are widely used in tunnel excavation, mining, demolition projects, underwater blasting, geological exploration, and in the defense and aerospace fields. Their molding and storage processes are sensitive to changes in ambient temperature, including thermal expansion mismatch, interfacial thermal debonding, binder softening, crystal phase transformation, and thermal cracking.

[0002] Existing research primarily relies on macroscopic continuum methods, employing techniques such as the finite element method (FEM) or finite difference method (FDM) to simulate macroscopic constitutive relations (e.g., elastoplastic models, Drucker-Prager models). Its limitations include: completely neglecting the internal granular structure, complex morphology, and particle size distribution of materials, failing to reflect stress concentration and anisotropy effects caused by real particle morphology; and being unable to directly simulate key micromechanical processes at the particle scale, such as fragmentation, interfacial debonding, and microcrack initiation and propagation. Damage is typically approximated by introducing homogenized damage variables, lacking a clear physical mechanism; and the use of uniform coefficients of thermal expansion and thermal conductivity fails to consider the thermal mismatch stress caused by the difference in thermal expansion coefficients between the crystalline and polymer phases, which is a key driving force for interfacial debonding and early damage. While the discrete element method can consider geometric irregularities and mechanical nonlinearities when simulating granular materials, it generally lacks a systematic integration of thermo-mechanical coupling effects, such as temperature-dependent material parameters (elastic modulus, bond strength), thermally induced interfacial degradation and debonding behavior, and the flow effect of binders at high temperatures.

[0003] Therefore, there is an urgent need to design a discrete element modeling method that integrates the morphology of crystalline polymer particles with the thermo-mechanical coupling effect. Summary of the Invention

[0004] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a discrete element modeling method that integrates the morphology of crystalline polymer particles with thermo-mechanical coupling. The aim is to establish a discrete element model of crystalline polymer particles with realistic particle morphology and develop a thermal contact model that considers binder softening and interface debonding. This solves the technical problem that conventional models cannot distinguish the material properties of crystals, polymer binders, and their interfaces.

[0005] To achieve the above objectives, according to one aspect of the present invention, a discrete element modeling method that integrates the morphology of crystalline polymer particles with thermo-mechanical coupling is provided, comprising the following steps: S1. Experimental calibration of thermo-mechanical parameters: Using a uniaxial compression device with a temperature control system, crushing tests were conducted on crystalline polymer particles under different temperature gradients to obtain their mechanical response, and a stiffness response function of normal stiffness as a function of temperature was established based on the experimental data. S2. Constructing a real-morphological particle discrete element model: A crystal template is constructed based on scanning electron microscope images, and the overall geometric morphology of the crystal polymer particles is obtained based on X-ray tomography images; the crystal template is placed in the discrete element software, and after compression molding and removal of out-of-contour units, an irregular and heterogeneous real-morphological particle discrete element model is obtained. S3. Obtain the response function of the strength parameters of crystalline polymer particles as a function of temperature: Set the contact stiffness of the discrete element model using the stiffness response function established in step S1, and perform thermo-mechanical coupled uniaxial loading simulation on the real-morphology particle discrete element model constructed in step S2 at the corresponding temperature; calibrate the strength parameters by comparing the force-displacement curves of the simulation and the experiment, and establish the strength response function of the strength parameters as a function of temperature. S4. Construct a thermo-mechanically coupled adhesive contact model, including establishing a heat transfer model and a contact constitutive model respectively; the heat transfer model integrates the heat conduction and thermal expansion mechanisms, and the contact constitutive model integrates the stiffness response function in step S1 and the strength response function in step S3; S5. Simulation and analysis of thermo-mechanical coupling behavior: Using the discrete element model of real-morphological particles constructed in step S2 and the thermo-mechanical coupling adhesive contact model constructed in step S4, uniaxial compression simulation is performed at different temperatures to analyze the deformation, breakage and micromechanical behavior of the particles.

[0006] Preferably, the temperature gradient in step S1 includes 30°C, 60°C, 80°C, 100°C and 120°C; the particles used in the experiment include spherical particles with an average diameter of 1.0 mm and columnar particles with a length of 2.5 mm and a diameter of 0.9 mm.

[0007] Preferably, the stiffness response function in step S1 is:

[0008] in, For normal stiffness, For temperature.

[0009] Preferably, step S2 specifically includes: S21. Crystal model construction based on SEM: The crystal outline is identified by scanning electron microscope image, the geometric outline is imported into the discrete element method, and spherical units are generated in the outline in the densest hexagonal packing method to create a crystal template. S22. CT-based overall particle modeling: The crystal template is placed inside a circular wall, and the porosity is controlled by a three-stage progressive compression. The spherical units outside the particle outline are removed by combining CT slice images to obtain an irregular, heterogeneous, real-morphology particle discrete element model.

[0010] Preferably, the intensity response function in step S3 is:

[0011] in, For normal adhesion force, For temperature.

[0012] Preferably, the construction step of the thermo-mechanically coupled adhesive contact model in step S4 includes: S41. Establish a heat transfer model, simplifying the material system into a network topology consisting of thermal containers and thermal contacts, where each spherical unit is a thermal container and the contact between particles forms a heat transfer path; The expression for the thermal expansion behavior of particles is as follows:

[0013] in, Let be the radius of the small ball. The coefficient of thermal expansion is... For temperature difference, This represents the expansion amount.

[0014] The expression for the additional thermal stress is as follows:

[0015] in, is the normal stiffness of the contact key; A is the cross-sectional area of ​​the contact key; L is the bond length, which is equal to the distance between the centers of the two spherical elements connected to the bond. The thermal expansion coefficient of the bond (take the average of the thermal expansion coefficients of the two small spheres at both ends). For temperature difference; The thermal expansion of the bond; S42. Establish a contact constitutive model. The thermo-mechanically coupled adhesive contact model consists of a set of orthogonal linear adhesive springs, and its constitutive equations for normal force and shear force are as follows:

[0016] in, For the normal component of linear force, This represents the tangential variation component of a linear force. Let be the normal stiffness of the contact as a function of temperature. The tangential stiffness of the contact varies with temperature; , These are the normal and tangential components of the interparticle overlap, respectively. Simulated tensile strength and shear strength The calculation formula is as follows:

[0017]

[0018] in, For the tensile strength of the bonded joint, Let r be the shear resistance of the contact bond, r be the radius of the smallest particle at both ends of the contact bond, and t be the unit thickness of the discrete element particle.

[0019] Preferably, in step S4, when > At that time, that is, normal force When the tensile force is greater than the tensile strength of the bond, the contact fails under tensile stress; when... > At that time, i.e., tangential force When the shear strength of the contact bond is greater than that of the bond bond, the contact fails under shear stress.

[0020] Preferably, in step S5, the uniaxial compression simulation is achieved by setting rigid loading plates at the top and bottom of the particle model. During the simulation, the force-displacement response, the number and distribution of cracks are recorded, and the debonding of the crystal-binder interface, crystal flow and energy dissipation are analyzed.

[0021] According to another aspect of the present invention, an application of the above-mentioned discrete element modeling method that integrates the morphology of crystalline polymer particles and the thermo-mechanical coupling effect is provided, and the method is applied to the discrete element simulation of the high-temperature pressing molding process of molding powder under actual working conditions.

[0022] In summary, compared with the prior art, the discrete element modeling method that integrates the morphology of crystalline polymer particles and the thermo-mechanical coupling effect provided by the present invention has the following advantages: 1. This invention realizes the realistic heat conduction process within and between heterogeneous composite particles; solves for thermal mismatch stress and deformation caused by the different thermal expansion coefficients of each phase; quantifies key microscopic parameters (such as bond strength and elastic modulus) as functions of temperature, thereby simulating key temperature effects such as interface strength degradation and binder softening; and simulates and distinguishes various microscopic mechanical behaviors induced by thermal stress, such as crystal flow and interfacial thermal debonding. It is applicable to simulating the thermal conduction characteristics, thermally induced deformation, thermal cracking, and interfacial debonding of breakable crystalline polymer particles under high-temperature or variable-temperature environments. It can effectively simulate the uniaxial crushing process of crystalline polymer particles at different temperatures and explore the microscopic mechanical mechanism under this process. Its theoretical basis can provide technical support for multi-field coupling research in crystalline polymer compression molding and frozen soil mechanics.

[0023] 2. This invention develops a discrete element model that integrates real geometric morphology, multiphase material properties, and thermo-mechanical coupling effects. It has significant theoretical and engineering application value for scientifically understanding the thermodynamic behavior of crystalline polymer particles and accurately predicting their molding process and long-term storage. Attached Figure Description

[0024] Figure 1 This is a flowchart of a discrete element modeling method that integrates the morphology of crystalline polymer particles with thermo-mechanical coupling, according to the present invention. Figure 2 This is a physical image of the temperature-controlled single-axis loading device in an embodiment of the present invention; Figure 3 These are force-displacement curves and crushing process diagrams at room temperature in embodiments of the present invention; Figure 4 This is a force-displacement curve and crushing process diagram at 60°C in an embodiment of the present invention; Figure 5 This is a force-displacement curve and crushing process diagram at 80°C in an embodiment of the present invention; Figure 6 This is a diagram illustrating the process of establishing a discrete element crystal template in an embodiment of the present invention; Figure 7 This is a diagram showing the morphology of crystalline polymer particles in an embodiment of the present invention; Figure 8 This is a diagram illustrating the compaction process of the crystalline polymer particle model in an embodiment of the present invention; Figure 9 This is a schematic diagram of the heat transfer mode in an embodiment of the present invention; Figure 10 This is a schematic diagram of the contact constitutive model in an embodiment of the present invention; Figure 11 This is a graph showing the variation of the stiffness of crystalline polymer particles with temperature in an embodiment of the present invention; Figure 12This is a graph showing the variation of the normal bonding force of the crystalline polymer particles with temperature in an embodiment of the present invention; Figure 13 This is a comparison diagram of a 30℃ simulation experiment in an embodiment of the present invention; Figure 14 This is a comparison diagram of a 60℃ simulation experiment in an embodiment of the present invention; Figure 15 This is a diagram illustrating the uniaxial compression simulation process in an embodiment of the present invention; Figure 16 These are crack evolution diagrams at different temperatures in embodiments of the present invention; Figure 17 This is an energy distribution diagram during particle crushing in an embodiment of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0026] Please see Figure 1 This embodiment provides a discrete element modeling method that integrates the morphology of crystalline polymer particles with thermo-mechanical coupling, including the following steps: S1. Experimental calibration of thermo-mechanical parameters: Using a uniaxial compression device with a temperature control system, crushing tests were conducted on crystalline polymer particles under different temperature gradients to obtain their mechanical response, and a stiffness response function of normal stiffness as a function of temperature was established based on the experimental data.

[0027] Please see Figure 2 The image shows a physical diagram of a temperature-controlled uniaxial loading device. Based on a uniaxial compression device, a temperature control unit is added. The temperature control unit consists of a temperature controller and a temperature control platform, which is positioned above the loading platform and also serves as part of the loading platform. Considering spherical particles with an average diameter of 1.0 mm and columnar particles with a length of 2.5 mm and a diameter of 0.9 mm, the temperature gradients are 30℃ (room temperature), 60℃, 80℃, 100℃, and 120℃, and the heating method is a high-temperature-force coupling. The crystalline polymer particles are placed on the heating platform and heated via contact heat transfer. After reaching the preset temperature, a constant temperature condition is maintained for uniaxial loading tests. Some test results are shown in [reference needed]. Figures 3-5 Analysis of the experimental data revealed that the mechanical behavior of the binder dominated the macroscopic response of the particles. (See also...) Figure 11 Based on the experimental data of spherical particles, the response function of normal stiffness as a function of temperature was obtained by fitting:

[0028] in, For normal stiffness, For temperature.

[0029] S2. Constructing a real-morphological particle discrete element model: A crystal template is constructed based on scanning electron microscope images, and the overall geometric morphology of the crystal polymer particles is obtained based on X-ray tomography images; the crystal template is placed in the discrete element software, and after compression molding and removal of out-of-contour units, an irregular and heterogeneous real-morphological particle discrete element model is obtained. Specifically, it includes: S21. SEM-based crystal model construction: Please refer to Figure 6 In the crystal micromorphology images scanned by SEM, representative crystal morphologies are selected, crystal profiles are identified by grayscale analysis, the geometric profile is imported into the discrete element method, and spherical units with a radius of 5μm are generated in the profile in the densest hexagonal packing manner. The generated crystal particle clusters are then used as crystal templates. S22. CT-based global particle modeling: Please refer to Figure 7-8 Crystal templates that meet the gradation requirements are placed inside a circular wall. Porosity is controlled by a three-stage progressive compression method. Combined with CT slice images, the real geometric shape of the particles is imported and the spherical units outside the particle outline are removed to obtain an irregular and heterogeneous real-morphological particle discrete element model. S3. Obtain the response function of the strength parameters of crystalline polymer particles as a function of temperature: Set the contact stiffness of the discrete element model using the stiffness response function established in step S1, and perform thermo-mechanical coupled uniaxial loading simulation on the real-morphology particle discrete element model constructed in step S2 at the corresponding temperature; calibrate the strength parameters by comparing the force-displacement curves of the simulation and the experiment, and establish the strength response function of the strength parameters as a function of temperature. Please see Figure 12 By repeatedly adjusting and calibrating the strength parameters, the simulated force-displacement curve was made to match the experimental results, and the strength response function was finally obtained as follows:

[0030] in, For normal adhesion force, For temperature.

[0031] S4. Construct a thermo-mechanically coupled adhesive contact model, including establishing a heat transfer model and a contact constitutive model respectively; the heat transfer model integrates the heat conduction and thermal expansion mechanisms, and the contact constitutive model integrates the stiffness response function in step S1 and the strength response function in step S3; The specific steps include: S41. Establish a heat transfer model; please refer to [link / reference]. Figure 9 The material system is simplified into a network topology consisting of thermal containers and thermal contacts, where each spherical unit is a thermal container and the contact between particles forms a heat transfer path. The expression for the thermal expansion behavior of particles is as follows:

[0032] in, Let be the radius of the small ball. The coefficient of thermal expansion is... For temperature difference, This represents the expansion amount.

[0033] The expression for the additional thermal stress is as follows:

[0034] in, is the normal stiffness of the contact key; A is the cross-sectional area of ​​the contact key; L is the bond length, which is equal to the distance between the centers of the two spherical elements connected to the bond. The thermal expansion coefficient of the bond (take the average of the thermal expansion coefficients of the two small spheres at both ends). For temperature difference; The thermal expansion of the bond; S42. Establish a contact constitutive model. The thermo-mechanically coupled adhesive contact model consists of a set of orthogonal linear adhesive springs, and includes both bonded and unbonded states. Please refer to [link / reference]. Figure 10 The stiffness of this set of linear bonded springs has a certain functional relationship with temperature, which restricts the relative shear slip between particles and determines the tensile and shear strength of the contact bond, but the particles can rotate about the contact axis. When the contact force exceeds the tensile strength, the bond will break, at which point the normal and shear components of the contact are both zero. When the shear force exceeds the shear strength and the normal force is compressive and less than the product of the friction coefficient and the normal force, the bond breaks but does not affect the magnitude of the contact force. When the bond breaks, the model degenerates into a slip model.

[0035] The constitutive equations for normal and shear forces are:

[0036] in, For the normal component of linear force, This represents the tangential variation component of a linear force. Let be the normal stiffness of the contact as a function of temperature. The tangential stiffness of the contact varies with temperature; , These are the normal and tangential components of the interparticle overlap, respectively. Simulated tensile strength and shear strength The calculation formula is as follows:

[0037]

[0038] in, For the tensile strength of the bonded joint, t represents the shear resistance of the contact bond, r represents the radius of the smallest particle at both ends of the contact bond, and t represents the unit thickness of the discrete element particle. when > At that time, that is, normal force When the tensile force is greater than the tensile strength of the bond, the contact fails under tensile stress; when... > At that time, i.e., tangential force When the shear strength of the contact bond is greater than that of the bond bond, the contact fails under shear stress.

[0039] S5. Simulation and analysis of thermo-mechanical coupling behavior: Using the discrete element model of real-morphological particles constructed in step S2 and the thermo-mechanical coupling adhesive contact model constructed in step S4, uniaxial compression simulation is performed at different temperatures to analyze the deformation, breakage and micromechanical behavior of the particles.

[0040] Discrete element simulations of the crystalline polymer particles were performed at the same temperature gradient (30℃ (room temperature), 60℃, 80℃, 100℃, 120℃). Uniaxial compression tests of the molding powder were simulated within the discrete element framework by placing planar loading plates at the top and bottom of the molding powder particles. The molding powder sample diameter was 0.81 mm. The parallel bond contact model parameters between the crystals were calibrated and did not change with temperature. However, considering thermal strain and thermal stress, the contact model between the binder and the crystals adopted the thermo-mechanical coupled bond contact model established above, with the normal-tangential stiffness ratio set to 1. Please refer to the simulation results. Figures 13-17 It can be observed that: microcracks mainly occur at the crystal-binder interface, and shear cracks are more numerous than tensile cracks, which is consistent with experimental phenomena; as the temperature increases, the proportion of frictional energy dissipation increases, indicating that the internal fluidity of the particles is enhanced; the work done by the external environment decreases with increasing temperature, proving that the particles are more easily broken at high temperatures.

[0041] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A discrete element modeling method that fuses the morphology of crystalline polymer particles with thermo-mechanical coupling, characterized by: The method comprises the following steps: S1. Thermal-mechanical parameter calibration: crush test of crystal polymer particles under different temperature gradients by a single-axis compression device with a temperature control system to obtain the mechanical response, and establishing a stiffness response function of normal stiffness changing with temperature based on the test data; S2. Construction of real morphology particle discrete element model: constructing a crystal template based on a scanning electron microscope image, and obtaining the overall geometric morphology of the crystal polymer particles based on an X-ray tomography image; placing the crystal template in a discrete element software, and after compression molding and profile outer cell removal, obtaining a non-regular, non-homogeneous real morphology particle discrete element model; S3. Obtaining the response function of the strength parameter of the crystal polymer particles changing with temperature: setting the contact stiffness of the discrete element model by using the stiffness response function established in step S1, and performing thermal-mechanical coupling uniaxial loading simulation on the real morphology particle discrete element model constructed in step S2 under the corresponding temperature; comparing the force-displacement curves of simulation and test, calibrating the strength parameter, and establishing a strength response function of the strength parameter changing with temperature; S4. Construction of thermal-mechanical coupling cohesive contact model, including establishing a heat transfer model and a contact constitutive model respectively; the heat transfer model fuses heat conduction and thermal expansion mechanism, and the contact constitutive model integrates the stiffness response function in step S1 and the strength response function in step S3; S5. Thermal-mechanical coupling behavior simulation and analysis: applying the real morphology particle discrete element model constructed in step S2 and the thermal-mechanical coupling cohesive contact model constructed in step S4 to perform uniaxial compression simulation under different temperatures, and analyzing the deformation, crushing and mesoscopic mechanical behavior of the particles.

2. The discrete element modeling method of fusion crystal polymer particle morphology and thermo-mechanical coupling action according to claim 1, characterized in that: The temperature gradient in step S1 includes 30℃, 60℃, 80℃, 100℃ and 120℃; the particles used in the test include spherical particles with an average diameter of 1.0mm and columnar particles with a length of 2.5mm and a diameter of 0.9mm.

3. The discrete element modeling method of fusion crystal polymer particle morphology and thermo-mechanical coupling action according to claim 1, characterized in that: The stiffness response function in step S1 is: wherein, is the normal stiffness, is the temperature.

4. The discrete element modeling method of fusion crystal polymer particle morphology and thermo-mechanical coupling action according to claim 1, characterized in that: Step S2 specifically includes: S21. Crystal model construction based on SEM: identifying the crystal profile through a scanning electron microscope image, importing the geometric profile in a discrete element, and generating spherical unit in a closest hexagonal packing manner within the profile line to create a crystal template; S22. Overall particle modeling based on CT: placing the crystal template in a circular wall, controlling porosity by a three-stage progressive compression, and removing spherical units outside the particle profile line in combination with a CT slice image to obtain a non-regular, non-homogeneous real morphology particle discrete element model.

5. The discrete element modeling method of fusion crystal polymer particle morphology and thermo-mechanical coupling action according to claim 1, characterized in that: The strength response function in step S3 is: wherein is the normal cohesive force, is the temperature.

6. The discrete element modeling method of fusion crystal polymer particle morphology and thermo-mechanical coupling action according to claim 1, characterized in that: The construction steps of the thermal-mechanical coupling cohesive contact model in step S4 include: S41. Establishing a heat transfer model, simplifying the material system into a network topology structure composed of heat containers and heat contacts, wherein each spherical unit is a heat container, and the contact between particles forms a heat transfer path; The expression of the thermal expansion behavior of the particles is as follows: wherein is the radius of the pellet, is the coefficient of thermal expansion, is the temperature difference, is the amount of expansion. The expression of the additional thermal stress is as follows: wherein, is the contact bond normal stiffness; A is the contact bond cross-sectional area; L is the bond length, taken as the distance between the centers of the two spherical units to which the bond is connected; is the thermal expansion coefficient of the bond, taken as the average of the thermal expansion coefficients of the two end spheres; is the temperature difference; is the thermal expansion of the bond; S42. Establishing a contact constitutive model, the thermal-mechanical coupling cohesive contact model is composed of a group of orthogonal linear cohesive springs, and the constitutive equations of the normal force and shear force of the springs are as follows: wherein is the normal variation component of the linear force, is the tangential variation component of the linear force, is a function of the normal stiffness of the contact as a function of temperature, is a function of the tangential stiffness of the contact as a function of temperature; , are the normal and tangential components of the inter-particle overlap, respectively; The formula for calculating the simulated tensile strength and the shear strength is as follows: wherein, is the tensile resistance of the contact bond, is the shear resistance of the contact bond, r is the radius of the smallest particle at the ends of the contact bond, and t is the unit thickness of the discrete element particle unit.

7. A discrete element modeling method of the fusion crystal polymer particle morphology and thermo-mechanical coupling action according to claim 6, characterized in that: In step S4, when the normal force is greater than the tensile resistance of the contact bond, the contact is tensile failure; when the tangential force is greater than the shear resistance of the contact bond, the contact is shear failure.​​ 8. The discrete element modeling method of fusion crystal polymer particle morphology and thermo-mechanical coupling action according to claim 1, characterized in that: In step S5, the uniaxial compression simulation is realized by setting rigid loading plates on the top and bottom of the particle model. The force-displacement response, crack number and distribution are recorded during the simulation process, and the crystal-binder interface debonding, crystal flow and energy dissipation rules are analyzed.

9. Use of the discrete element modeling method of the thermomechanical coupling of the fusion-crystal polymer particle morphology according to any one of claims 1 to 8, characterized in that, The method is applied to the discrete element simulation of the high-temperature compression molding process of molding powder under actual working conditions.

Images