An euler domain partitioning method for explosive material blast simulation
By using the Eulerian domain method to perform concentric circular arc surface partitioning and two-dimensional structured element stretching in the simulation of explosive material impact, the problem of insufficient mesh generation in the existing technology is solved, and more efficient and accurate simulation is achieved.
Patent Information
- Application Number
- CN202211008910.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-08-22
- Publication Date
- 2025-12-16
- Estimated Expiration
- 2042-08-22
AI Technical Summary
In existing technologies for simulating the impact of explosive materials, mesh generation is insufficient to satisfy the equidistant diffusion characteristics of the explosive material at the center, resulting in insufficient accuracy and confidence in the simulation.
The Eulerian domain partitioning method is adopted. By dividing the Eulerian domain into concentric arc surfaces on the end face, and stretching the two-dimensional structured unit to generate Eulerian domain unit, it is ensured that the unit diffuses at equal distances with the explosive material as the center, which conforms to the propagation law of explosive shock wave.
It improves the accuracy and confidence of simulation calculations, simplifies the processing difficulty and time of mesh generation, and ensures the stability and accuracy of calculations.
Smart Images
Figure CN115374671B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of simulation, more particularly, to an Euler domain partitioning method for explosion material explosion impact simulation. BACKGROUND
[0002] With the increasing use of explosion material impact in military and civilian, domestic and foreign scholars have carried out in-depth research on the explosion material impact characteristics, including explosion material impact propagation process, expansion movement process, structure dynamic response and damage process. At present, the main research methods are experimental research and simulation calculation research. The experimental implementation has the disadvantages of long cycle and high cost, and only some explosion characteristics under specific conditions can be obtained. The simulation calculation research intuitively reproduces the explosion material impact propagation process, expansion movement process, structure dynamic response and damage process, can carry out repeated analysis and research for multiple working conditions, and the simulation calculation results are reasonable and accurate, have the characteristics of short cycle and low cost, and are widely accepted and recognized by experts and scholars.
[0003] An existing underwater far-field explosion material impact simulation calculation method based on gradient grid technology determines the type of initiation source, the amount of explosive or detonation energy, the shape and the blast distance; establishes a fine Euler grid wrapped around the initiation source; establishes a coarse Euler grid in the far-field water area under a certain blast distance; respectively assigns the fine Euler grid and the coarse Euler grid with corresponding material parameters; sets the water area boundary conditions; sets the gradient grid command and submits the software calculation; extracts the shock wave peak pressure at a certain blast distance, and compares it with the Cole underwater explosion 533 formula calculation value; according to the comparison result, the next calculation step is determined: if the simulation result pressure value and the 533 formula calculation value are in good agreement, step 9 is performed; if the relative difference between the simulation result pressure value and the 533 formula calculation value exceeds the error range, return to step 3. The present application greatly reduces the underwater far-field explosion material impact simulation calculation amount by reasonable grid size setting and application of gradient grid technology, and can ensure the calculation accuracy.
[0004] As a research means, it is difficult and important for simulation calculation to capture the propagation process characteristic parameters of explosion shock wave and energy wave. As known, the unit shape and unit mass have great influence on the simulation calculation results, therefore, how to partition high-quality units suitable for simulating the propagation process of shock wave and energy wave generated by explosion material explosion impact is particularly important. In the above technical solution, the grid is only divided in terms of density from far to near, it is difficult to achieve the purpose of controlling the grid, and it is difficult to meet the equal distance diffusion characteristics with explosion material as the center, resulting in the accuracy and confidence of simulation. SUMMARY
[0005] The present application provides an Euler domain partition method for explosion material explosion impact simulation to overcome the poor simulation effect in the prior art, and the Euler domain topology structure of the simulated explosive is partitioned, the characteristics of the explosion shock wave and energy wave propagating at the same speed and distance to the surroundings, and the energy wave and shock wave rapidly attenuating can be captured, and the simulation calculation accuracy and confidence are greatly improved.
[0006] To solve the above technical problems, the technical scheme adopted by the present application is as follows: an Euler domain partition method for explosion material explosion impact simulation, comprising the following steps:
[0007] Step one: calculating the geometric size of the explosion material;
[0008] Step two: drawing the Euler domain of the cylindrical explosion material impact and dividing it into a fluid domain and an explosion material domain;
[0009] Step three: partitioning the end face of the Euler domain, and dividing the fluid domain into a plurality of concentric circular arc faces;
[0010] Step four: further dividing the partition result of step three into a two-dimensional structured unit, and stretching the two-dimensional structured unit to generate the Euler domain unit of the explosion material impact.
[0011] In the above technical scheme, the end face is divided into a plurality of concentric circular arc faces by dividing the end face into concentric circles with different radii, the stretched unit is diffused at equal distances, the quality of the Euler domain unit is effectively controlled by partitioning the Euler domain unit, the Euler domain unit has the characteristics of equal distance diffusion with the explosion material as the center, the Euler domain unit meets the parameters of the explosion shock wave propagation law and the characteristics of capturing the explosion shock wave, and the calculation stability and calculation precision of the explosion material impact finite element model are ensured.
[0012] The Euler domain is generally used for describing air or liquid, and is mainly used for studying the liquid characteristics and fluid-structure coupling characteristics, and the Euler domain can better simulate the fluid characteristics and fluid-structure coupling characteristics of the explosion material explosion area (such as air or water).
[0013] Preferably, in step one, the radius r and height h of the cylindrical explosion material impact effect are determined according to the known explosion material mass M and density p.
[0014] Preferably, in step two, the Euler domain of the cylindrical explosion material impact with a radius R and a height H is drawn, the explosion material domain with a radius r and a height h is divided on one end of the cylindrical body with a radius R and a height H, and the area between the radius r and the radius R is the fluid domain.
[0015] Preferably, the specific process of step three is as follows:
[0016] S3.1: Divide the end face of the Euler domain into at least three equal parts, select one part, and divide a plurality of circular arc surfaces on the end face of the fluid domain in the part, from the center of the fluid domain to the outer edge, and sequentially mark them as G1, G2, G3,..., Gn respectively;
[0017] S3.2: Take the midpoint of the inner circle arc of the circular arc surface G1, and divide the circular arc surface G1 into three parts by two division lines passing through the midpoint and respectively parallel to the two side lines of the circular arc surface G1.
[0018] S3.3: In the manner of S3.2, sequentially separate the circular arc surfaces of odd-numbered items, and finally complete the division of the Euler domain.
[0019] By equally dividing the circular arc surfaces in this way, the shock wave and energy wave generated by the explosion can be evenly and equidistantly propagated to the surrounding, the energy wave and shock wave rapidly decay after the explosion, and the characteristic parameter isosurface of the shock wave (such as velocity and energy) is the same as the distance from the explosion point. The segmented circular arc surfaces can make the length of each segment of the inner circle arc and the outer circle arc of the segmented arc surface close and generate a quadrilateral, so that the corresponding arc surface can generate a grid with equal or similar shape, and the interval division is to avoid too many divisions affecting the grid quality. Under this balance, the shape and quality of the grid unit are accurately controlled, so that the Euler domain is stretched and the unit is equally diffused, further ensuring that the Euler domain unit has the characteristic of equidistant diffusion around the explosion material.
[0020] Preferably, in S3.1, the specific process of dividing the circular arc surface is as follows:
[0021] S3.1.1: In the fluid domain, a plurality of concentric circles are made with the center of the cylinder as the center, and the radii of the concentric circles are r1, r2, r3,..., rn from small to large. n ; wherein, when n is odd, r n = r (n-1) + 0.5kr(n-1); when n is even, r n = r (n-1) + 0.5krn; r1 = r.
[0022] S3.1.2: Divide the end face of the Euler domain into at least three equal parts using the division line, and in one part, the adjacent concentric circles form a circular arc surface.
[0023] Preferably, in S3.1, one part of the fluid domain is selected, and a plurality of concentric circular arcs are made with the center of the cylinder as the center in the fluid domain, and the circular arcs are r1, r2, r3,..., rn from small to large. n , and the two adjacent circular arcs form a circular arc surface.
[0024] ; wherein, when n is odd, r n = r(n-1) +0.5kr(n-1);when n is even, then r n = r (n-1) +0.5krn;r1=r.
[0025] Preferably, in S3.1, the Euler domain end face is divided into at least four equal parts, and the four equal parts can be achieved by only two lines passing through the center and perpendicular to each other, which is more convenient to operate.
[0026] Preferably, the specific process of step four is:
[0027] S4.1: According to the size of the explosive material, the two-dimensional structured unit of one part of the Euler domain end face divided in step three is divided into two-dimensional structured units;
[0028] S4.2: The two-dimensional structured unit in S4.1 is copied along the center to other equal end faces to obtain the two-dimensional structured unit of the Euler domain end face, and the two-dimensional structured unit is stretched to generate the Euler domain unit of the explosive material impact;
[0029] S4.3: The Euler domain unit of step S4.2 is grouped and integrated into explosive material domain unit and fluid domain unit to obtain the Euler domain unit of the explosive material impact simulation.
[0030] Preferably, in S4.2, the two-dimensional structured unit is stretched to generate the Euler domain unit of the explosive material impact by the sweep method.
[0031] Preferably, in step two, the drawn Euler domain is imported into the finite element software, and the fluid domain and the explosive material domain are divided at one end of the cylinder through the entity editing function.
[0032] Compared with the prior art, the beneficial effects of the present application are: through the division and setting of the Euler domain unit, the processing difficulty and time of the grid division before simulation simulation can be simplified, the quality of the Euler domain unit can be effectively controlled, and the Euler domain unit can also guarantee the characteristics of the explosive material as the center of equal distance diffusion, so that the Euler domain unit meets the parameters of the characteristics of the explosive shock wave propagation law and the capture of the explosive shock wave, greatly improves the simulation calculation efficiency and accuracy, and makes the confidence of the simulation simulation higher. BRIEF DESCRIPTION OF DRAWINGS
[0033] Figure 1 The flow chart of the Euler domain division method for the explosive material explosion impact simulation of the present application;
[0034] Figure 2 The schematic diagram of the explosive material domain and the fluid domain division of the present application;
[0035] Figure 3 The schematic diagram of the arc surface division of the present application;
[0036] Figure 4 A schematic diagram of the arc surface segmentation of the present application;
[0037] Figure 5 A schematic diagram of the Euler domain unit of the explosion material impact simulation of the present application;
[0038] Figure 6 A pressure simulation distribution cloud chart of the present application;
[0039] Figure 7 A schematic diagram of the concentric circle division of the present application. DETAILED DESCRIPTION
[0040] The drawings are only used for illustrative description, and cannot be understood as a limitation on the patent; in order to better illustrate the embodiments, some components in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. The positional relationship described in the drawings is only used for illustrative description, and cannot be understood as a limitation on the patent.
[0041] The same or similar reference numerals in the drawings of the embodiments of the present application correspond to the same or similar components; in the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "long", "short" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the positional relationship in the drawings are only used for illustrative description, and cannot be understood as a limitation on the patent, and for those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.
[0042] The technical solutions of the present application will be further specifically described below through specific embodiments and in conjunction with the drawings:
[0043] Embodiment 1
[0044] As Figure 1 shown is an embodiment 1 of an Euler domain division method for explosion material explosion impact simulation, comprising the following steps:
[0045] Step 1: Calculate the geometric size of the explosive material; according to the known explosive material mass M=6.37 Kg and density ρ=1690 Kg / m 3 Determine the radius r=0.1 m and height h=0.12 m of the cylinder of the explosive material impact effect.
[0046] Step two: according to the formula H = ch, R = cr, when c = 7, R = 0.7m, H = 0.84m. Draw the Euler domain of the cylindrical explosive material impact with radius R and height H, and import the drawn Euler domain into the finite element software. Divide the one end of the cylinder with radius R and height H into the explosive material domain with radius r and height h through the entity editing function, and the area between the radius r and the radius R is the fluid domain, as shown in Figure 2 .
[0047] Step three: divide the end face of the Euler domain, and divide the fluid domain into multiple concentric circular arc surfaces. The specific process is as follows: S3.1: divide the end face of the Euler domain into four equal parts, and select one part. Divide four circular arc surfaces on the end face of the fluid domain of the part, from the center of the fluid domain to the outer edge, and mark them as G1, G2, G3,..., Gn in turn. In this embodiment, two straight lines passing through the center of the circle and parallel to the global coordinate system are used to divide the end face of the explosive material domain and the fluid domain into four equal parts by using the quick edit function of the finite element analysis software. The circular arc surfaces are divided by using the surface edit function, which are G1, G2, G3, and G4. The inner arc radius of G1 is 0.1m, and the outer arc radius is 0.2m; the inner arc radius of G2 is 0.2m, and the outer arc radius is 0.3m; the inner arc radius of G3 is 0.3m, and the outer arc radius is 0.5m; the inner arc radius of G4 is 0.5m, and the outer arc radius is 0.7m. As shown in Figure 3 .
[0048] S3.2: Take the midpoint of the inner circle arc of the circular arc surface G1, and divide the circular arc surface G1 into three parts by using two division lines passing through the midpoint and parallel to the two side lines of the circular arc surface G1. In this embodiment, the midpoint is obtained by using the line command, and the division lines are obtained by using the surface edit command.
[0049] S3.3: In the manner of S3.2, the circular arc surfaces of odd-numbered items are sequentially separated, and the division of the Euler domain is finally completed, as shown in Figure 4 .
[0050] Step four: further divide the two-dimensional structured unit according to the division result of step three, and stretch the two-dimensional structured unit to generate the Euler domain unit of the explosive material impact. The specific process is as follows:
[0051] S4.1: According to the size of the unit size of the explosive material, the two-dimensional structured unit is divided into the Euler domain end face of one part in step three by using automesh;
[0052] S4.2: Copy the two-dimensional structured unit in S4.1 to other equal-division end faces along the center of the circle to obtain the two-dimensional structured unit of the Euler domain end face, and stretch the two-dimensional structured unit by the line drag command sweep method to generate the Euler domain unit as shown in the explosion material impact.
[0053] S4.3: Group and integrate the Euler domain unit of step S4.2 into the explosion material domain unit and the fluid domain unit to obtain the Euler domain unit for explosion material impact simulation as shown in Figure 5
[0054] The Euler domain unit shown in Figure 5 The pressure simulation distribution cloud diagram as shown in Figure 6
[0055] The working principle or workflow of the embodiment: the end face is divided into multiple concentric circular arc faces by dividing the end face into concentric circles with different radii. The segmented circular arc faces can make the length of each segment of the inner and outer circular arcs of the segmented arc faces close and form a quadrilateral, so that the corresponding arc faces can generate grids with equal or similar shapes. The interval division is to avoid affecting the grid quality by dividing too much. In this balance, the shape and quality of the grid unit are accurately controlled. When stretching the two-dimensional structure unit, the stretched unit is diffused at equal distances. Dividing and setting the Euler domain unit can not only effectively control the quality of the Euler domain unit, but also ensure that the Euler domain unit has the characteristic of equal-distance diffusion with the explosion material as the center, so that the Euler domain unit meets the parameters of the characteristics of the explosion shock wave propagation and the capture of the explosion shock wave, to ensure the calculation stability and accuracy of the explosion material impact finite element model
[0056] The beneficial effects of the embodiment: by dividing the Euler domain unit into multiple sets and accurately controlling the quality of the Euler domain unit by complementary interference of each set, the processing difficulty and time of grid division before simulation simulation can be simplified, and the quality of the Euler domain unit can be effectively controlled. At the same time, the Euler domain unit also has the characteristic of equal-distance diffusion with the explosion material as the center, so that the Euler domain unit meets the parameters of the characteristics of the explosion shock wave propagation and the capture of the explosion shock wave, greatly improves the simulation calculation efficiency and accuracy, and makes the simulation simulation more reliable.
[0057] The main evaluation index of the patent is whether the Euler domain unit has the characteristic of equal-distance diffusion with the explosion material as the center. This characteristic is more in line with the characteristics of the explosion shock wave, and the calculation result is relatively accurate.
[0058] Example 2
[0059] Embodiment 2 of the Euler domain partition method for explosion material explosion shock simulation, based on embodiment 1, the difference from embodiment 1 is that in S3.1, the specific process of the circular arc surface partition is:
[0060] S3.1.1: In the fluid domain, take the center of the cylinder as a plurality of concentric circles, and the radii of the concentric circles are r1, r2, r3,..., r n ; wherein, when n is odd, then r n =r (n-1) +0.5kr(n-1); when n is even, then r n =r (n-1) +0.5krn; r1=r=0.1m, k=1;
[0061] The concentric circle structure is shown in Figure 7 , and the radii are r1=0.1m, r2=0.2m, r3=0.3m, r4=0.5m, and r5=0.7m.
[0062] S3.1.2: Use the split line to divide the end face of the Euler domain into four equal parts, and in one of them, the adjacent concentric circles form a circular arc surface.
[0063] The remaining features and working principles are consistent with embodiment 1.
[0064] Embodiment 3
[0065] Embodiment 3 of the Euler domain partition method for explosion material explosion shock simulation, based on embodiment 1, the difference from embodiment 1 is that in S3.1, select one of the fluid domains, and in the fluid domain, take the center of the cylinder as a plurality of concentric circular arcs, and the radii of the concentric circular arcs are r1, r2, r3, r4, r5, and the adjacent two circular arcs form a circular arc surface;
[0066] ; wherein, when n is odd, then r n =r (n-1) +0.5kr(n-1); when n is even, then r n =r (n-1) +0.5krn; r1=r=0.1m, k=1. r1=0.1m, r2=0.2m, r3=0.3m, r4=0.5m, r5=0.7m.
[0067] The remaining features and working principles of this embodiment are consistent with embodiment 1.
[0068] Obviously, the above embodiments of the present application are merely exemplary but not intended to limit the embodiments of the present application. Based on the above description, any other variations or changes can be made by those skilled in the art without departing from the spirit and principles of the present application. It is not necessary to list all the embodiments here. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall fall within the scope of the claims of the present application.
Claims
1. An Eulerian domain partitioning method for explosive material blast shock simulation, characterized by, The method comprises the following steps: Step one: calculating the geometric size of the explosive material; Step two: drawing the Euler domain of the cylindrical explosive material impact and dividing it into a fluid domain and an explosive material domain; Step three: dividing the end face of the Euler domain and dividing the fluid domain into a plurality of concentric circular arc faces; S3.1: dividing the end face of the Euler domain into at least four equal parts, selecting one part, and dividing a plurality of circular arc faces on the end face of the fluid domain in the part, from the center of the fluid domain to the outer edge, and sequentially recording them as G1, G2, G3,..., Gn respectively; S3.1.1: Select one of the fluid domains, and in the fluid domain, make a plurality of concentric circles with the center of the cylinder as the center, and the radii of the concentric circles are from small to large, respectively , , ... ; wherein, when n is odd, ; when n is even, ; ; S3.1.2: dividing the end face of the Euler domain into at least four equal parts using the division line, and forming a circular arc face between adjacent concentric circles in one of the parts; S3.2: taking the midpoint of the inner circle arc of the circular arc face G1, and dividing the circular arc face G1 into three parts by two division lines passing through the midpoint and respectively parallel to the two side lines of the circular arc face G1; S3.3: sequentially separating the circular arc faces of odd-numbered items in the manner of S3.2, and finally completing the division of the Euler domain; Step four: further dividing the two-dimensional structured unit according to the division result of step three to generate the Euler domain unit of the explosive material impact.
2. The Eulerian domain partitioning method for explosive material blast simulation of claim 1, wherein, In step one, the radius r and height h of the cylindrical explosive material impact effect are determined according to the known explosive material mass M and density p.
3. The Eulerian domain partitioning method for explosive material blast simulation of claim 2, wherein, In step two, the Euler domain of the cylindrical explosive material impact is drawn, and the explosive material domain with a radius of r and a height of h is divided on one end of the cylindrical explosive material with a radius of R and a height of H, and the area between the radius r and the radius R is the fluid domain.
4. The Eulerian domain partitioning method for explosive material blast simulation of claim 1, wherein, The specific steps of step four are: S4.1: determining the size of the unit according to the explosive material, and dividing the Euler domain end face of one part completed in step three into a two-dimensional structured unit; S4.2: copying the two-dimensional structured unit in S4.1 to other equally divided end faces along the center to obtain the two-dimensional structured unit of the Euler domain end face, and stretching the two-dimensional structured unit to generate the Euler domain unit of the explosive material impact; S4.3: grouping and integrating the explosive material domain unit and the fluid domain unit of the Euler domain unit in step S4.2 to obtain the Euler domain unit of the explosive material impact simulation.
5. The Eulerian domain partitioning method for explosive material blast simulation of claim 4, wherein, In S4.2, the two-dimensional structured unit is stretched to generate the Euler domain unit of the explosive material impact by the sweeping method.
6. The Eulerian domain partitioning method for explosion impact simulation of an explosive material according to any one of claims 1-5, characterized in that, In step two, the drawn Euler domain is imported into the finite element software, and the fluid domain and the explosive material domain are divided on one end of the cylinder through the entity editing function.