CN112395712A - Method, device and equipment for simulating shape of irregular particles - Google Patents
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Abstract
本发明公开了一种不规则颗粒的形状模拟方法，所述模拟方法基于离散元计算方法，其包括如下步骤：a、利用贝塞尔曲线表征待分析颗粒材料的几何形态，并获得待分析颗粒材料的基于贝塞尔曲线的颗粒数学描述；b、对多个待分析颗粒材料进行接触判断，以确定颗粒材料相互之间的接触关系；c、对接触的颗粒材料进行接触特征分析，以获取颗粒材料之间的接触特征。本发明的一种不规则颗粒的形状模拟方法更易于实现对不规则粒子的建模工作，具备显著的可迁移性。相应地，本发明还提供了一种不规则颗粒的形状模拟装置及设备。
The invention discloses a shape simulation method of irregular particles. The simulation method is based on a discrete element calculation method, which includes the following steps: a. Using a Bezier curve to characterize the geometric shape of the particle material to be analyzed, and obtaining the particle to be analyzed Mathematical description of particles based on Bezier curves; b. Judging the contact of multiple particulate materials to be analyzed to determine the contact relationship between the particulate materials; c. Conducting contact characteristic analysis on the contacting particulate materials to obtain Contact characteristics between particulate materials. The method for simulating the shape of an irregular particle of the present invention is easier to realize the modeling work of the irregular particle, and has remarkable mobility. Correspondingly, the present invention also provides a shape simulation device and equipment for irregular particles.
Description
Technical Field
The invention relates to the field of material mechanics, in particular to a method, a device and equipment for simulating the shape of irregular particles.
Background
The granular material is widely existed in nature and has important engineering significance for the research of the mechanical property of the granular material. Particle shape discrete element calculation method the discrete element method is the most important numerical tool for simulating particle materials at present, and simulates the macroscopic mechanical behavior of the particle materials through the interaction among particles and the capture of motion information. The simulation of the traditional particle shape discrete element calculation method mostly adopts regular particles such as discs, spheres and the like for calculation, and the method is widely applied to various projects due to the characteristics of high efficiency and easy realization. However, the particles visible in reality mostly have irregular shapes, and the irregularity of the particles has a significant influence on the macroscopic properties of the particles, so that a model for a discrete element calculation method of the irregular particles needs to be developed.
When developing a new discrete meta-particle model, three factors need to be addressed: accuracy, computational efficiency, and migratability. The existing discrete element calculation method considering irregular particles mainly comprises a single particle method and a composite particle method, and the composite particle method has the defects of low calculation efficiency, unreal contact parameters and the like. Therefore, the existing method for constructing irregular particles is still limited by the shape of specific particles, cannot combine multiple particle models in the same discrete element calculation method model, lacks mobility, and cannot be widely applied.
Therefore, there is a need to provide an improved irregular particle shape simulation method, apparatus and device that can combine multiple particle models to overcome the above-mentioned drawbacks.
Disclosure of Invention
The invention aims to provide a method for simulating the shape of irregular particles, which is more easy to realize the modeling work of the irregular particles, so that the method can be suitable for the particle shape analysis of particle materials with any shape, and meanwhile, the control points of a Bezier curve have higher flexibility in describing the particle shape; in addition, the contact judgment and the contact characteristic analysis adopted in the invention can be integrated with other existing particle models, and the mobility is remarkable. Correspondingly, the invention also provides a device and equipment for simulating the shape of the irregular particles.
In order to achieve the above object, the present invention discloses a method for simulating the shape of irregular particles, wherein the method for simulating is based on a discrete element calculation method, and comprises the following steps:
a. characterizing the geometric form of the particle material to be analyzed by using a Bezier curve, and obtaining a particle mathematical description of the particle material to be analyzed based on the Bezier curve;
b. carrying out contact judgment on a plurality of particle materials to be analyzed so as to determine the contact relationship among the particle materials;
c. and performing contact characteristic analysis on the contacted particle materials to obtain contact characteristics between the particle materials.
Preferably, in the step a, the closed particle boundaries are formed by connecting N segments of bezier curves end to obtain a mathematical description of the particles of the particle material to be analyzed, and N is a natural number greater than 1.
Preferably, said step of obtaining a bessel curve-based mathematical description of the particles of the particulate material to be analyzed comprises the following steps:
a1, dividing the geometric surface of the particulate material to be analyzed into N portions, passing through P0、P1、P2……PN-1The N points are connected, each part is respectively characterized by a Bezier curve, and for any part, the connection point PiAnd Pi+1Simultaneously representing the head and tail control points of the Bezier curve;
a2, characterizing the geometrical shape of the granular material to be analyzed by a third-order Bessel curve, wherein the characterization expression is as follows:
B(t)＝(1-t)3Q0+3(1-t)2tQ1+3(1-t)t2Q2+t3Q3 0≤t≤1
wherein B (t) represents a point on a Bezier curve, t represents a control parameter, Q0、Q1、Q2、Q3Representing a control point;
a3, calculating the position of the support point, wherein the calculation mode of the support point is as follows:
sA(v)＝B(tv)
wherein, tvRepresenting the corresponding control parameter when the supporting direction is v;
a4, calculating the particle mass m and the moment of inertia I of the particle material to be analyzed based on the Bezier curve, scanning the control parameter t to obtain a plurality of boundary points, and assuming that the coordinates of the boundary points are (x)0,y0),(x1,y1)……(xn-1,yn-1) The solution for the particle mass and moment of inertia is then as follows:
preferably, in the step a3,
support direction v and support line direction B' (t)v) In a vertical relationship, v.B' (t)v)＝0。
Preferably, in the step b, the contact judgment of the plurality of particle materials to be analyzed is based on a GJK algorithm for computational analysis, and specifically includes the following steps:
b1, randomly selecting two original supporting directions v(0)And v(1)Determining the support point on any two particulate materials according to the support direction, calculating the Minkowski and W of the support point(0)And W(1)For a given two units a and B, the minkowski sum is defined as:
AΘB＝{PA-PB|PA∈A,PB∈B}
wherein A Θ B represents the Minkowski sum of A and B, PAAnd PBRespectively represent arbitrary points in units a and B;
b2, defining an initial simplex W(0)W(1)Is the simplex closest to the origin;
b3, in the k-th iterationDetermining a support direction v(k)Determining a support direction v(k)Corresponding support point W(k)Judging whether the support point is in the opposite direction of the support direction;
b4, determining simplex W(i)W(j)W(k)Whether or not the origin is included, and calculating the distance from the origin to the simplex W(i)W(k)And to simplex W(j)W(k)Defining the simplex with smaller distance as the new simplex closest to the origin;
b5, repeating the steps b3 to b4 until reaching the sword catching criterion or the maximum iteration number.
Preferably, in said step B1, if the minkowski sum contains the origin, the two units a and B are in contact, and if the minkowski sum does not contain the origin, the two units a and B are not in contact.
Preferably, in the step c, the contact characteristic analysis is performed on the contacted particle material, and the method specifically includes the following steps:
c1 calculating the amount of overlap delta between particles from Minkowski sumsn：
δn＝minv·[sA(v)-sB(-v)]
Wherein s isA(v)-sB(-v) denotes the support point of the Minkowski sum of units A and B;
c2, creating a polygon inside the Minkowski and the two units A and B, obtaining the three support points of the initial polygon in the contact detection by the GJK algorithm, W(0)、W(1)、W(2)；
c3, iteratively, successively taking the vertical direction of the simplex closest to the origin as the new support direction to obtain a new support point, expanding the polygon until close to the minkowski and the upper closest support point to the origin.
Accordingly, the present invention also discloses an apparatus for analyzing the particle shape of a particulate material, comprising:
the mathematical description module is used for representing the geometric form of the particle material to be analyzed by using the Bezier curve and obtaining the particle mathematical description of the particle material to be analyzed based on the Bezier curve;
the contact judgment module is used for performing contact judgment on a plurality of particle materials to be analyzed so as to determine the contact relation among the particle materials;
and the characteristic analysis module is used for carrying out contact characteristic analysis on the contacted particle materials so as to obtain contact characteristics among the particle materials.
Preferably, in the mathematical description module, the closed particle boundaries are formed by connecting N segments of bezier curves end to obtain a mathematical description of the particles of the particle material to be analyzed, where N is a natural number greater than 1.
Meanwhile, the invention also discloses a device for simulating the shape of the irregular particles, which comprises a memory, a processor and a computer program which is stored in the memory and can run on the processor, wherein the processor executes the computer program to realize the steps of the method for simulating the shape of the irregular particles.
Compared with the prior art, the method, the device and the equipment for simulating the shape of the irregular particles obtain the geometric shapes of the particles in the particle material through the Bezier curve, then judge whether the particles are contacted, and analyze and determine the contact characteristics among the particles if the particles are contacted; therefore, the method, the device and the equipment for simulating the shape of the irregular particles are easier to realize the modeling work of the irregular particles, so that the method, the device and the equipment are suitable for analyzing the shape of the particles of the particle materials with any shape, and meanwhile, the control points of the Bezier curve have higher flexibility in describing the shape of the particles; in addition, the contact judgment and the contact characteristic analysis adopted in the invention can be integrated with other existing particle models, and the mobility is remarkable.
The invention will become more apparent from the following description when taken in conjunction with the accompanying drawings, which illustrate embodiments of the invention.
Drawings
Fig. 1 is a schematic flow chart of a method for simulating the shape of irregular particles according to the present invention.
FIG. 2 is a flow chart of mathematical description of particles in the method for simulating the shape of irregular particles according to the present invention.
Fig. 3 is a schematic diagram of mathematical description of particles based on bezier curves.
Fig. 4 is a schematic diagram of cubic bezier curve generation.
FIG. 5 is a schematic flow chart of the contact judgment of the particle material in the irregular particle shape simulation method according to the present invention.
Fig. 6 is a schematic diagram of the contact determination between particles.
FIG. 7 is a schematic flow chart of the particle material contact characteristic analysis in the irregular particle shape simulation method according to the present invention.
FIG. 8 defines a schematic of particle contact geometry.
FIG. 9 is a schematic diagram of the calculation of the contact characteristics between particles.
FIG. 10 is a schematic structural diagram of a shape simulation apparatus for irregular particles according to the present invention.
Detailed Description
Embodiments of the present invention will now be described with reference to the drawings, wherein like element numerals represent like elements. As described above, the invention provides a method for simulating the shape of irregular particles, which is easier to implement the modeling work on irregular particles, so that the method can be applied to the simulation analysis of the particle shape of particle materials with any shape, and meanwhile, the control points of the bezier curve enable higher flexibility in describing the particle shape; in addition, the contact judgment and the contact characteristic analysis adopted in the invention can be integrated with other existing particle models, and the mobility is remarkable.
Referring to fig. 1, fig. 1 is a schematic flow chart of a method for simulating the shape of irregular particles according to the present invention, wherein the simulation analysis method is based on a discrete component calculation method; as shown in fig. 1, the method for simulating the shape of irregular particles of the present invention mainly comprises the following steps.
S100, representing the geometric form of the particle material to be analyzed by using a Bezier curve, and obtaining the particle mathematical description of the particle material to be analyzed based on the Bezier curve; in the step, N sections of Bessel curves are connected end to form a closed particle boundary so as to obtain particle mathematical description of the particle material to be analyzed, wherein N is a natural number greater than 1, and in a specific application process, a smaller curve can be obtained by increasing the value of N, so that the particle material to be analyzed has higher flexibility in description and more accurate representation of the geometric form of the particle material; specifically, referring to fig. 2 in combination, the present step further includes the following steps:
step S101 of dividing the geometric surface of the particulate material to be analyzed into N portions, passing P0、P1、P2……PN-1The N points are connected, each part is respectively characterized by a Bezier curve, and for any part, the connection point PiAnd Pi+1Simultaneously, two control points at the head and the tail of the Bezier curve are also represented, and Qi represents the control points of the Bezier curve, and is specifically shown in FIG. 3; and in this step, the tangential directions of the two adjacent parts at the connecting point are the same, as shown by P in FIG. 31And P2(ii) a The geometric surface of the granular material can be represented by the N divided parts, and the larger the value of N is, the finer the geometric surface of the granular material to be analyzed is divided, the more accurate the geometric surface can be represented, so that the geometric surface of each irregular granular material can be accurately represented, and the geometric surface of the regular granular material can be more represented;
step S102, representing the geometric shape of the particle material to be analyzed by adopting a third-order Bessel curve, wherein the representation expression is as follows:
B(t)＝(1-t)3Q0+3(1-t)2tQ1+3(1-t)t2Q2+t3Q3 0≤t≤1
wherein B (t) represents a point on a Bezier curve, t represents a control parameter, Q0、Q1、Q2、Q3Representing the control points, the generation of a specific third order bezier curve is shown in fig. 4; in the present step, the first step is carried out,
in addition, b (t) can also be expressed in the form of a matrix as follows:
step S103, calculating the position of a support point, wherein the calculation mode of the support point is as follows:
sA(v)＝B(tv)
wherein, tvRepresenting the corresponding control parameter when the supporting direction is v; in this step, the support direction v and the support line direction B' (t)v) In a perpendicular relationship, i.e. v.B' (t)v) B' (t) is a tangent to point B (t) on the bezier curve, the support point is a tangent to a straight line perpendicular to the support direction and tangential to the particle profile after the support direction is determined, and the tangent point is the support point.
Step S104, calculating the particle mass m and the moment of inertia I of the particle material to be analyzed based on the Bezier curve, scanning the control parameter t to obtain a plurality of boundary points, and assuming that the coordinates of the boundary points are (x)0,y0),(x1,y1)……(xn-1,yn-1) The solution for the particle mass and moment of inertia is then as follows:
s200, performing contact judgment on a plurality of particle materials to be analyzed to determine the contact relationship among the particle materials; in the step, the contact judgment of the particle materials to be analyzed is calculated and analyzed based on a GJK (Gilbert-Johnson-Keerthialgorithm) algorithm, and the GJK supports collision detection among any convex body shapes through a support function, so that the contact relation among the particle materials to be analyzed can be accurately determined in the step; specifically, referring to fig. 5 and fig. 6 in combination, the step of determining the contact of the plurality of particle materials to be analyzed further includes the following steps:
step S201, two original supporting directions v are randomly selected(0)And v(1)Determining the support point on any two particulate materials according to the support direction, calculating the Minkowski and W of the support point(0)And W(1)For a given two units a and B, the minkowski sum is defined as:
AΘB＝{PA-PB|PA∈A,PB∈B}
wherein A Θ B represents the Minkowski sum of A and B, PAAnd PBRespectively represent arbitrary points in units a and B;
in this step, the two units a and B are in contact if the minkowski sum contains the origin, whereas they are not if the minkowski sum does not contain the origin. Wherein the direction v is supported(0)It is generally assumed that the centroid of cell a points to the centroid of cell B, and it is checked whether the calculated support point is opposite to the support direction, and if so, a non-contact flag is returned.
Step S202, defining an initial simplex W(0)W(1)Is the simplex closest to the origin; in this step, W(0)W(1)The term "line" refers to a line segment formed by two points W (0) and W (1).
Step S203, in the k-th iteration, the support direction v is determined(k)Determining a support direction v(k)Corresponding support point W(k)Checking whether the support point is in a direction opposite to the support direction; in this step, the direction v is supported(k)I.e. is a simplex W(i)W(j)Pointing in the normal direction of the origin, and if the support point is in the opposite direction of the support direction, returning a non-contact mark, i.e. the two granular materials are not in contact; the iteration means that new support points are generated by continuously selecting new support directions so as to generate new simplex, whether the generated simplex contains an original point is judged, and if yes, the two particle materials are judged to be in contact; if not, continue to selectCalculating and detecting the new support direction; in addition, the values from the origin to the simplex W are calculated separately(i)W(k)And to simplex W(j)W(k)And defining the simplex with the smaller distance as the new simplex closest to the origin.
Step S204, determining simplex W(i)W(j)W(k)Whether or not the origin is included, and calculating the distance from the origin to the simplex W(i)W(k)And to simplex W(j)W(k)Defining the simplex with smaller distance as the new simplex closest to the origin; in this step, the distance from the origin to the adjacent simplex is calculated and compared, and the simplex having the smaller distance is selected as the simplex closest to the origin, so that the simplex including the origin can be calculated and found through a limited number of iterations to determine that the two granular materials are in contact with each other.
Step S205, repeating steps S202 to S204 until reaching a sword receiving criterion or the maximum iteration times; in this step, the steps S202 to S203 are repeated to obtain an accurate contact relationship between the particulate materials, wherein when the number of iterations is about 10, a relatively good convergence effect can be obtained, and in the actual application process, the convergence criterion and the maximum number of iterations can be set according to a specific precision requirement as long as the target precision requirement can be met.
Step S300, carrying out contact characteristic analysis on the contacted particle materials to obtain contact characteristics among the particle materials; in this step, the contact characteristics between the particles are mainly as follows: overlap of particles deltanA contact normal direction n, a contact tangent direction τ, etc., wherein the contact normal direction is perpendicular to the contact surface and the tangent direction is parallel to the contact surface; in addition, the contact characteristic analysis is mainly performed based on the EPA algorithm; please refer to fig. 7 to 9, wherein the contact pattern between particles and wall is defined as fig. 8; specifically, the contact characterization of the contacted particulate material further comprises the steps of:
step S301 of calculating the amount of overlap delta between particles from Minkowski sumsn：
δn＝minv·[sA(v)-sB(-v)]
Wherein s isA(v)-sB(-v) denotes the support point of the Minkowski sum of units A and B;
step S302, creating a polygon inside the Minkowski and the two units A and B, obtaining three support points, W, of the initial polygon in the contact detection by GJK algorithm(0)、W(1)、W(2)；
Step S303, continuously taking the vertical direction of the simplex closest to the origin as a new support direction through iteration to obtain a new support point, and expanding the polygon until the support point is close to minkowski and the upper closest to the origin.
Accordingly, the present invention further provides a shape simulation apparatus for irregular particles, referring to fig. 10, fig. 10 is a schematic structural diagram of the shape simulation apparatus for irregular particles of the present invention, as shown in the figure, the simulation apparatus includes:
a mathematical description module 401, configured to characterize the geometric form of the particulate material to be analyzed by using a bezier curve, and obtain a bezier curve-based mathematical description of the particles of the particulate material to be analyzed;
a contact judgment module 402, which is used for performing contact judgment on a plurality of particle materials to be analyzed so as to determine the contact relationship among the particle materials;
a characteristic analysis module 403, configured to perform contact characteristic analysis on the contacted particulate materials to obtain contact characteristics between the particulate materials.
Preferably, in the mathematical description module 401, a closed particle boundary is formed by connecting N segments of bezier curves end to obtain a mathematical description of the particles of the particulate material to be analyzed. In a specific application process, a smaller curve can be obtained by increasing the value of N, so that even various irregular granular materials can be described by a plurality of fine curves, and the geometric form of the granular materials with different shapes can be represented; so that the particle material to be analyzed has higher flexibility in describing the particle material and the geometric shape of the particle material is more accurately characterized
Meanwhile, the invention also provides a device for simulating the shape of the irregular particles, which corresponds to the method for simulating the shape of the irregular particles shown in FIG. 1; it comprises a memory, a processor and a computer program stored in the memory and executable on the processor, such as a shape analysis program for irregular particle materials, a contact relation analysis program between particles, etc. The processor, when executing the computer program, implements the steps of the above-described irregular particle shape simulation method embodiments, as in steps S100-S300. In addition, the shape simulation device of the irregular particles can be a desktop computer, a notebook, a palm computer, a cloud server and other computing devices; and the shape simulation device of the irregular particles can include, but is not limited to, a processor and a memory.
In summary, according to the method, the device and the equipment for simulating the shape of the irregular particles, disclosed by the invention, after the geometric shapes of the particles in the particle material are obtained through the bezier curve, whether the particles are contacted or not is judged, and if the particles are contacted, the contact characteristics among the particles are analyzed and determined; therefore, the analysis method and the analysis device for the particle shape of the granular material can realize the modeling work of irregular particles more easily, so that the method and the device can be suitable for the particle shape analysis of the granular material with any shape, and meanwhile, the control points of the Bezier curve have higher flexibility in describing the particle shape; in addition, the contact judgment and the contact characteristic analysis adopted in the invention can be integrated with other existing particle models, and the mobility is remarkable.
The present invention has been described in connection with the preferred embodiments, but the present invention is not limited to the embodiments disclosed above, and is intended to cover various modifications, equivalent combinations, which are made in accordance with the spirit of the present invention.
Claims (10)
1. A method for simulating the shape of irregular particles, which is based on a discrete element calculation method, is characterized by comprising the following steps:
a. characterizing the geometric form of the particle material to be analyzed by using a Bezier curve, and obtaining a particle mathematical description of the particle material to be analyzed based on the Bezier curve;
b. carrying out contact judgment on a plurality of particle materials to be analyzed so as to determine the contact relationship among the particle materials;
c. and performing contact characteristic analysis on the contacted particle materials to obtain contact characteristics between the particle materials.
2. The method for simulating the shape of the irregular particles according to claim 1, wherein in the step a, the closed particle boundaries are formed by connecting N sections of Bessel curves end to obtain the mathematical description of the particles of the particle material to be analyzed, and N is a natural number greater than 1.
3. A method for simulating the shape of irregular particles according to claim 2, wherein said step of obtaining a bezier curve based mathematical description of the particles of the particulate material to be analyzed comprises the following steps:
a1, dividing the geometric surface of the particulate material to be analyzed into N portions, passing through P0、P1、P2……PN-1The N points are connected, each part is respectively characterized by a Bezier curve, and for any part, the connection point PiAnd Pi+1Simultaneously representing the head and tail control points of the Bezier curve;
a2, characterizing the geometrical shape of the granular material to be analyzed by a third-order Bessel curve, wherein the characterization expression is as follows:
B(t)＝(1-t)3Q0+3(1-t)2tQ1+3(1-t)t2Q2+t3Q3 0≤t≤1
wherein B (t) represents a point on a Bezier curve, t represents a control parameter, Q0、Q1、Q2、Q3Representing a control point;
a3, calculating the position of the support point, wherein the calculation mode of the support point is as follows:
sA(v)＝B(tv)
wherein, tvRepresenting the corresponding control parameter when the supporting direction is v;
a4, calculating the particle mass m and the moment of inertia I of the particle material to be analyzed based on the Bezier curve, scanning the control parameter t to obtain a plurality of boundary points, and assuming that the coordinates of the boundary points are (x)0,y0),(x1,y1)……(xn-1,yn-1) The solution for the particle mass and moment of inertia is then as follows:
4. the method for simulating the shape of irregular particles according to claim 3, wherein in step a3,
support direction v and support line direction B' (t)v) In a vertical relationship, v.B' (t)v)＝0。
5. The method for simulating the shape of an irregular particle according to claim 3, wherein in the step b, the contact judgment of the plurality of particle materials to be analyzed is based on a GJK algorithm for calculation and analysis, and the method further comprises the following steps:
b1, randomly selecting two original supporting directions v(0)And v(1)Determining the support point on any two particulate materials according to the support direction, calculating the Minkowski and W of the support point(0)And W(1)For a given two units a and B, the minkowski sum is defined as:
AΘB＝{PA-PB|PA∈A,PB∈B}
wherein A Θ B represents the Minkowski sum of A and B, PAAnd PBRespectively represent arbitrary points in units a and B;
b2, defining an initial simplex W(0)W(1)Is the simplex closest to the origin;
b3, in the k-th iteration, the support direction v is determined(k)Determining a support direction v(k)Corresponding support point W(k)Judging whether the support point is in the opposite direction of the support direction;
b4, determining simplex W(i)W(j)W(k)Whether or not the origin is included, and calculating the distance from the origin to the simplex W(i)W(k)And to simplex W(j)W(k)Defining the simplex with smaller distance as the new simplex closest to the origin;
b5, repeating the steps b3 to b4 until reaching the sword catching criterion or the maximum iteration number.
6. A method as claimed in claim 5, wherein in said step B1, if the Minkowski sum contains an origin, the two units A and B are in contact, and if the Minkowski sum does not contain an origin, the two units A and B are not in contact.
7. The method for simulating the shape of an irregular particle according to claim 5, wherein the step c of analyzing the contact characteristics of the contacted particle material comprises the following steps:
c1 calculating the amount of overlap delta between particles from Minkowski sumsn：
δn＝minv·[sA(v)-sB(-v)]
Wherein s isA(v)-sB(-v) denotes the support point of the Minkowski sum of units A and B;
c2, creating a polygon inside the Minkowski and the two units A and B, obtaining the three support points of the initial polygon in the contact detection by the GJK algorithm, W(0)、W(1)、W(2)；
c3, iteratively, successively taking the vertical direction of the simplex closest to the origin as the new support direction to obtain a new support point, expanding the polygon until close to the minkowski and the upper closest support point to the origin.
8. An apparatus for simulating the shape of irregular particles, comprising:
the mathematical description module is used for representing the geometric form of the particle material to be analyzed by using the Bezier curve and obtaining the particle mathematical description of the particle material to be analyzed based on the Bezier curve;
the contact judgment module is used for performing contact judgment on a plurality of particle materials to be analyzed so as to determine the contact relation among the particle materials;
and the characteristic analysis module is used for carrying out contact characteristic analysis on the contacted particle materials so as to obtain contact characteristics among the particle materials.
9. The irregular particle shape simulation apparatus according to claim 8,
in the mathematical description module, N sections of Bezier curves are connected end to form a closed particle boundary so as to obtain the particle mathematical description of the particle material to be analyzed, wherein N is a natural number larger than 1.
10. An apparatus for simulating the shape of an irregular particle, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the method for simulating the shape of an irregular particle according to any one of claims 1 to 7.
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| CN114969892A (en) * | 2022-04-20 | 2022-08-30 | 西安建筑科技大学 | Method and system for defining and quantifying contact mode of crushed stone granules and storage medium |
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