CN114417680B - Topology optimization method, system, device and storage medium for improving dynamic deletion rate - Google Patents
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Abstract
The invention relates to a topology optimization method, a system, equipment and a storage medium for improving dynamic deletion rate, wherein the method comprises the following steps: establishing an initial structure finite element model and a structure topological optimization mathematical model based on an engineering structure, and determining topological optimization related parameters for improving the dynamic deletion rate; carrying out finite element solution on the initial structure finite element model to obtain element sensitivity, structural stress uniformity, structural volume fraction index and dynamic deletion rate of the current step, and calculating the structure volume of the next step according to the dynamic deletion rate of the current step; solving a sensitivity threshold value according to the volume of the next step structure, and updating the initial structure finite element model according to the unit sensitivity and the sensitivity threshold value; and circularly and iteratively executing the solving and optimizing steps until the optimized structure finite element model reaches a preset constraint condition and a preset convergence condition, and outputting the optimized topological structure of the engineering structure. The invention can output the structure with optimal performance.
Description
Technical Field
The present invention relates to the field of structure optimization technologies, and in particular, to a topology optimization method, system, device, and storage medium for improving dynamic deletion rate.
Background
The topological optimization is an important branch in the field of structural optimization design, and has become a mature design method after decades of development, and the method has the characteristics of high design efficiency, high design freedom and the like, and is widely applied to engineering structural design and academic research. The topological optimization can delete low-efficiency materials in the structure under certain constraint conditions, and find the optimal distribution of the materials in a design domain, so that the structure with light weight and excellent performance is obtained. At present, people face various problems such as material resource shortage, environmental impact and technical competition, and the advantages of topology optimization make the problems become one of important methods for solving the problems.
The deletion rate is an important parameter for structural topology optimization, and the gradual optimization of the material in each iteration step can be controlled to be an optimal form. However, in the current topology optimization method, the deletion rate is a constant that is fixed and unchanged, but the number of entity units changes dynamically in the structure optimization process, so that the current fixed deletion rate is difficult to match with the dynamic change of the units, and the phenomena of low optimization efficiency, unstable optimization process and even failure in optimization occur. Therefore, it is necessary to improve the way of determining the deletion rate, and to provide a new topology optimization method to accomplish the optimization design goal more efficiently and stably.
Disclosure of Invention
In view of the above, it is necessary to provide a topology optimization method, a system, a device and a storage medium for improving a dynamic deletion rate, so as to solve the problem that a conventional fixed deletion rate topology optimization method cannot effectively delete redundant materials due to low optimization efficiency and unstable optimization.
In order to solve the above problem, in a first aspect, the present invention provides a topology optimization method for improving a dynamic deletion rate, which is applied in a structure optimization design process, and includes:
establishing an initial structure finite element model and a structure topology optimization mathematical model based on an engineering structure, distributing an initial unit state variable value for each unit in the initial structure finite element model, and determining topology optimization related parameters for improving the dynamic deletion rate;
carrying out finite element model on the initial structureFinite element solution to obtain element sensitivityDegree of structural stress uniformityStructural volume fraction indexAnd a firstStep dynamic deletion rateAccording to said secondStep dynamic deletion rateCalculate the firstVolume of step structure;
According to the said firstVolume of step structureSolving for sensitivity thresholdAnd according to the cell sensitivityAnd the sensitivityThreshold valueUpdating the initial structure finite element model;
and circularly and iteratively executing the solving and updating steps until the updated structure finite element model reaches a preset constraint condition and a preset convergence condition, and outputting the optimized topological structure of the engineering structure.
Further, the structure topology optimization mathematical model comprises:
whereinin order to have an average flexibility of the structure,andrespectively, the load and the unit displacement vector,in order to transpose the symbols,in order to be a constraint condition, the method comprises the following steps of,in order to optimize the target volume,is the total number of the entity units,is as followsThe volume of each unit cell is equal to the volume of each unit cell,is as followsThe state variable of each unit is changed into a state variable,representThe unit is a physical unit which is a unit,representsThe unit is an empty unit;
the allocating of the initial element state variable value to each element in the initial structure finite element model comprises that the initial element of each element in the initial structure finite element model is a solid element;
the topology optimization related parameters for improving the dynamic deletion rate comprise the minimum deletion rateAnd an upper limit of increase of deletion rate。
whereinis as followsThe displacement vector of the node of each unit,is as followsA cell stiffness matrix of individual cells.
the degree of uniformity of the structural stress by using the coefficient of variationAnd (3) solving:whereinis a firstThe von Mises stress of the individual cells,is the mean value of von Mises stress of all the entity units in the current iteration step.
indexing the volume fraction of the structure by means of relative difference quotientAnd (3) solving:whereinfor the current number of iteration steps,is as followsThe volume of the step structure is increased,in order to optimize the target volume,to design the domain volume.
Further, said first stepStep dynamic deletion rateThe solving process comprises the following steps:
based on the structural stress uniformityAnd structural volume fraction indexFor the second step, by means of a sine functionSolving the step dynamic deletion rate:whereinis as followsThe dynamic rate of deletion is stepped up to,in order to minimize the rate of deletion,an upper limit is added to the erasure rate.
Further, the method according to the second aspectStep dynamic deletion rateCalculate the firstVolume of step structureThe method comprises the following steps:。
further, the unit sensitivity is determined according to the unit sensitivityAnd the sensitivity thresholdOptimizing the initial structure finite element model in terms of size, comprising:
when the cell sensitivity of any cellGreater than the sensitivity thresholdIf so, converting the unit into an entity unit;
when the cell sensitivity of any cellLess than the sensitivity thresholdThen the cell is converted to an empty cell.
Further, the preset constraint condition includes: the structure volume reaches the optimized target volume;
the preset convergence condition comprises the following steps:whereinthe value of the objective function, i.e. the average compliance of the structure,for the number of steps of the current iteration,is the tolerance of convergence and is,are integers.
In a second aspect, the present invention further provides a topology optimization system for improving a dynamic deletion rate, which is applied to a structure optimization design process, and includes:
the system comprises an establishing module, a dynamic deletion rate improving module and a dynamic deletion rate improving module, wherein the establishing module is used for establishing an initial structure finite element model and a structure topology optimization mathematical model based on an engineering structure, allocating initial unit state variable values for each unit in the initial structure finite element model and determining related parameters of topology optimization for improving the dynamic deletion rate;
a solving module for carrying out finite element solving on the initial structure finite element model to obtain element sensitivityDegree of structural stress uniformityStructural volume fraction indexAnd a first step ofStep dynamic deletion rateAccording to said secondStep dynamic deletion rateCalculate the firstVolume of step structure;
An update module for updating according to the secondVolume of step structureSolving for sensitivity thresholdAnd according to the cell sensitivityAnd the sensitivity thresholdUpdating the initial structure finite element model;
and the output module is used for circularly and iteratively executing the solving and updating steps until the updated structure finite element model reaches a preset constraint condition and a preset convergence condition, and outputting the optimized topological structure of the engineering structure.
In a third aspect, the present invention further provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the topology optimization method for improving dynamic deletion rate when executing the computer program.
In a fourth aspect, the present invention further provides a computer storage medium, in which a computer program is stored, and the computer program, when executed by a processor, implements the steps in the topology optimization method for improving dynamic deletion rate as described above.
The beneficial effects of adopting the above embodiment are:
in the invention, in the structure optimization design process of the building material, an improved dynamic deletion rate calculation method is constructed by considering the structure volume fraction index and the structure stress uniformity, and a topological optimization method calculation process for improving the dynamic deletion rate is established, so that a finite element solution can be carried out on an initial structure finite element model according to a structure topological optimization mathematical model, the dynamic deletion rate is calculated according to the stress condition of the structure in each iteration step, and the problem that the traditional fixed deletion rate cannot be dynamically changed and optimization failure is possibly caused is solved. And then optimizing the finite element model of the building material according to the dynamic deletion rate, outputting the optimized topological structure of the building material, and effectively reducing the use of redundant materials through a reasonable optimized structure, thereby not only meeting the requirements of actual engineering, but also ensuring the optimal performance of the structure. The optimization method in the invention requires fewer iteration steps, and has high calculation efficiency and good stability.
Drawings
FIG. 1 is a flowchart illustrating an embodiment of a topology optimization method for improving dynamic deletion rate according to the present invention;
FIG. 2 is a field diagram of a cantilever design in an embodiment of the present invention;
FIG. 3(a) is a graph of the calculation result of the fixed erasure rate in an embodiment of the present invention;
FIG. 3(b) is a graph of improved dynamic erasure rate calculations in an embodiment provided by the present invention;
FIG. 4 is a graph comparing structure strain energy change history of a fixed erasure rate topology optimization method and a topology optimization method for improving dynamic erasure rate according to an embodiment of the present invention;
fig. 5 is a graph comparing the unit deletion amount history of the topology optimization method with a fixed deletion rate and the topology optimization method with an improved dynamic deletion rate according to an embodiment of the present invention;
FIG. 6 is a schematic structural diagram of an embodiment of a topology optimization system for improving dynamic erasure rate according to the present invention;
fig. 7 is an electronic device provided by the present invention.
Detailed Description
The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form a part hereof, and which together with the embodiments of the invention serve to explain the principles of the invention and not to limit its scope.
In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.
The present invention provides a topology optimization method, system, device and storage medium for improving dynamic deletion rate, which are described below.
Referring to fig. 1, fig. 1 is a schematic flow chart of an embodiment of a topology optimization method for improving dynamic deletion rate according to the present invention, and an embodiment of the present invention discloses a topology optimization method for improving dynamic deletion rate, which is applied to a structure optimization design process, and includes:
step S101: establishing an initial structure finite element model based on an engineering structure and a structural topological optimization mathematical model, distributing an initial unit state variable value for each unit in the initial structure finite element model, and determining topological optimization related parameters for improving the dynamic deletion rate;
it should be noted that the topology optimization method of the present invention is applicable to the minimum compliance topology optimization design of any engineering structure, and in a specific embodiment of the present invention, the engineering structure includes a building material that can be stressed, such as a cantilever beam. The initial structure finite element model based on the engineering structure comprises a cantilever beam finite element model.
The structure topology optimization mathematical model comprises:whereinin order to have an average flexibility of the structure,andrespectively, the load and the unit displacement vector,in order to transpose the symbols,in order to be a constraint condition, the method comprises the following steps of,in order to optimize the target volume,is the total number of the entity units,is as followsThe volume of each unit cell is equal to the volume of each unit cell,is as followsThe state variable of each unit is changed into a state variable,representsThe unit is a solid unit which is composed of a plurality of units,representsThe unit is an empty unit;
and then assigning an initial element state variable value to each element in the initial structure finite element model, wherein the initial element of each element in the initial structure finite element model is a solid element, that is, all element state variables are 1 in the first iteration.
Wherein the topology optimization related parameters for improving the dynamic deletion rate comprise the minimum deletion rateAnd an upper limit of increase of deletion rate。
Step S102: carrying out finite element solution on the initial structure finite element model to obtain element sensitivityStructural stress uniformityStructural volume fraction indexAnd a firstStep dynamic deletion rateAnd according to the firstStep dynamic deletion rateCalculate the firstVolume of step structure;
It can be understood that the displacement of each degree of freedom of the node can be obtained by performing finite element solution on the initial structure finite element model, and then subsequent parameters can be solved according to the displacement of each degree of freedom of the node.
In one embodiment of the invention, the cell sensitivityThe solving process comprises the following steps:
whereinis as followsThe displacement vector of the node of each unit,is as followsA cell stiffness matrix of individual cells.
In one embodiment of the invention, the degree of structural stress uniformityThe solving process comprises the following steps:
degree of structural stress uniformity by using coefficient of variationAnd (3) solving:whereinis as followsThe von Mises stress of the individual cells,is the mean value of von Mises stress of all the entity units in the current iteration step.
Wherein,the larger the structure stress distribution, the more uneven the structure stress distribution, and the influence of unreal numerical values caused by stress concentration can be reduced by adopting the variation coefficient to calculate the structure stress uniformity, so that the structure stress uniformity is reflected more truly.
In one embodiment of the invention, the structure volume fraction indicatorThe solving process comprises the following steps:
index structure volume integral number by means of relative difference quotientAnd (3) solving:wherein, in the process,for the current number of iteration steps,is as followsThe volume of the step structure is increased,in order to optimize the target volume,to design the domain volume.
In one embodiment of the invention, the secondStep dynamic deletion rateThe solving process comprises the following steps:
based on the degree of structural stress uniformityAnd structural volume fraction indexBy means of sine functionSolving the step dynamic deletion rate:whereinis as followsThe dynamic rate of deletion is stepped on to the extent that,in order to minimize the rate of deletion,an upper limit is added to the erasure rate.
By making the unit stress distribution uniformAnd structural volume fraction indexThe influence of the multiplication method and the unit deletion rate is comprehensively considered, the optimal dynamic deletion rate of each iteration step can be obtained, and compared with the traditional fixed deletion rate mode, the optimization efficiency and quality of the method are greatly improved.
And according toStep dynamic deletion rateThe solving process of the method can be known to adopt a larger deleting rate when the structural stress is uniformly distributed in the early stage of optimization and the structural residual volume is larger than the target volume, and adopt a smaller deleting rate when the structural stress is uniformly distributed and the structural residual volume approaches the target volume in the later stage of optimization, and the dynamic change is carried out along with iteration, so that the material deleting process is carried out efficiently, and compared with the traditional fixed deleting rate topological optimization method, the method has higher calculation efficiency and better stability.
In one embodiment of the invention, according toStep dynamic deletion rateCalculate the firstVolume of step structureThe method comprises the following steps:。
step S103: according to the firstVolume of step structureSolving for sensitivity thresholdAnd according to cell sensitivityAnd sensitivity thresholdUpdating the initial structure finite element model according to the size of the initial structure finite element model;
wherein according to the firstVolume of step structureSolving for sensitivity thresholdIn the design process, all units in the design domain need to be sequenced according to the sensitivity level of the units to determineVolume of step structureHaving the number of units according toVolume of step structureThe number of physical cells that are present determines the sensitivity threshold, for example, if there are 1000 cells in the design domain, and the cell sensitivity is ranked as:if, ifCorresponding to a design with 700 physical units, then。
In one embodiment of the invention, the sensitivity is based on the cellAnd sensitivity thresholdUpdating the initial structure finite element model according to the size of the initial structure finite element model, comprising:
when the cell sensitivity of any cellGreater than a sensitivity thresholdIf so, converting the unit into an entity unit, namely changing the unit state variable of the unit into 1;
when the cell sensitivity of any cellLess than a sensitivity thresholdThen the cell is converted to an empty cell, i.e. the cell state variable for the cell is changed to 0.
Step S104: and circularly and iteratively executing the solving and updating steps until the updated structure finite element model reaches a preset constraint condition and a preset convergence condition, and outputting the optimized topological structure of the engineering structure.
In one embodiment of the present invention, the preset constraint condition includes: the structure volume reaches the optimized target volume;
it can be understood that, in the iteration process, if the structure volume of a certain step is the same as the optimization target volume, the structure finite element model updated in the current iteration step can be considered to reach the preset constraint condition.
The preset convergence condition comprises the following steps:whereinthe value of the objective function, i.e. the average compliance of the structure,for the current number of iteration steps,is the tolerance of convergence and is,are integers.
It can be understood that the preset convergence condition means that the change of the objective function value in the last 10 iterations is very small and tends to be smooth, i.e. the objective function reaches convergence.
And when the preset constraint condition and the preset convergence condition are reached, ending the iteration process and outputting an updated model, wherein the updated model comprises the optimal topological structure of the engineering structure.
In the invention, in the structure optimization design process of the building material, an improved dynamic deletion rate calculation method is constructed by considering the structure volume fraction index and the structure stress uniformity, and a topological optimization method calculation process for improving the dynamic deletion rate is established, so that a finite element solution can be carried out on an initial structure finite element model according to a structure topological optimization mathematical model, the dynamic deletion rate is calculated according to the stress condition of the structure in each iteration step, and the problem that the traditional fixed deletion rate cannot be dynamically changed and optimization failure is possibly caused is solved. And then optimizing the finite element model of the building material according to the dynamic deletion rate, outputting the optimized topological structure of the building material, and effectively reducing the use of redundant materials through a reasonable optimized structure, thereby not only meeting the requirements of actual engineering, but also ensuring the optimal performance of the structure. The optimization method in the invention requires fewer iteration steps, and has high calculation efficiency and good stability.
For a more convenient understanding of the present invention, reference is made to an embodiment of the present invention, referring to fig. 2, and fig. 2 is a diagram illustrating a cantilever design according to an embodiment of the present invention.
1) Establishing a cantilever beam finite element model, applying load and boundary conditions, solidifying the left end of the figure 2, and enabling the middle point of the cantilever end to be acted by the load F =100N and to be downward. The designed domain has a length of 80mm and a height of 50mm, and is divided into 80 × 50 grids, and 4000 square units are designed. Measuring elastic modulus to 100GPa, taking Poisson's ratio to 0.3, and establishing topological optimization mathematical modelSetting related parameters of topological optimization method for improving dynamic deletion rate and volume constraintTaking out the mixture of 0.4 percent,taking out the weight of the mixture of 0.02,taking 0.02, the dynamic deletion rate is [0.02,0.04 ]]And varied within the interval.
2) Performing finite element solution to obtain element sensitivityThe unit sensitivity calculation method comprises the following steps:(ii) a And determining the degree of structural stress uniformityStructural volume fraction indexAnd calculating the current step deletion rateAnd according toCalculating next step structure volume:。
3) From the next step structure volumeCalculating sensitivity thresholdSensitivity of the if empty cellGreater than a sensitivity thresholdThe cell is converted to a physical cell (i.e., the cell state variable of the cell is changed to 1) if the physical cell sensitivity is highLess than a sensitivity thresholdThe element is converted to an empty element (i.e., the element state variable of the element is changed to 0), thereby updating the cantilever finite element model.
Wherein the sensitivity threshold valueThe calculation method specifically comprises the following steps: all units in the design domain are sorted according to the sensitivity level, and at the momentByIt is decided, for example, that there are 1000 cells in the design domain,if, ifCorresponding to a design with 700 physical units, then;
4) Repeating 2), 3) until the structure volume reaches the target volume, the target function satisfying the following convergence criterion:. Referring to fig. 3(a) and fig. 3(b), fig. 3(a) is a graph of a calculation result of a fixed erasure rate in an embodiment of the present invention, and fig. 3(b) is a graph of a calculation result of an improved dynamic erasure rate in an embodiment of the present invention.
It can be seen from fig. 3(a) and 3(b) that the final structures obtained by the two methods are similar, and only slight differences exist. In the optimization process of the cantilever beam model, the strain energy of the final structure obtained by the fixed deletion rate topological optimization method and the final structure obtained by the method is 2.3246N ∙ mm and 2.3170N ∙ mm respectively, and the strain energy of the final structure obtained by the method provided by the invention is smaller, which shows that the method provided by the invention has relatively better optimization quality.
Referring to fig. 4, fig. 4 is a graph comparing the structural strain energy change history of the topology optimization method with the fixed erasure rate and the topology optimization method with the improved dynamic erasure rate according to an embodiment of the present invention. The deleting rate of the fixed deleting rate topological optimization method is the average value of the upper limit and the lower limit of the deleting rate of the topological optimization method for improving the dynamic deleting rate, wherein the deleting rate of the fixed deleting rate topological optimization method is 0.03.
Referring to fig. 5, fig. 5 is a graph comparing the unit erasure count history of the topology optimization method with the fixed erasure rate and the topology optimization method with the improved dynamic erasure rate according to an embodiment of the present invention.
As can be seen from fig. 5, with the method provided by the present invention, when the structure at the early stage of optimization has more redundant materials and the stress distribution is very uneven, the number of single-step unit deletions is large, and as the structure is continuously close to the target volume and the stress distribution is relatively even, the number of single-step unit deletions gradually decreases. Compared with a fixed deletion rate topology optimization method which needs 65 steps to reach a convergence condition, the method provided by the invention can converge only in 47 steps to obtain an optimal structure, the efficiency is improved by 27.7%, and the method provided by the invention is more efficient and reasonable.
In order to better implement the topology optimization method for improving dynamic deletion rate in the embodiment of the present invention, on the basis of the topology optimization method for improving dynamic deletion rate, correspondingly, please refer to fig. 6, where fig. 6 is a schematic structural diagram of an embodiment of the topology optimization system for improving dynamic deletion rate provided by the present invention, and an embodiment of the present invention provides a topology optimization system 600 for improving dynamic deletion rate, including:
the establishing module 601 is used for establishing an initial structure finite element model and a structure topology optimization mathematical model based on an engineering structure, allocating an initial element state variable value to each element in the initial structure finite element model, and determining a topology optimization related parameter for improving a dynamic deletion rate;
a solving module 602, configured to perform finite element solution on the initial structure finite element model to obtain element sensitivityDegree of structural stress uniformityStructural volume fraction indexAnd a firstStep dynamic deletion rateAnd according to the firstStep dynamic deletion rateCalculate the firstVolume of step structure;
An update module 603 forVolume of step structureSolving for sensitivity thresholdAnd according to cell sensitivityAnd sensitivity thresholdUpdating the initial structure finite element model according to the size of the initial structure;
and the output module 604 is configured to perform the solving and updating steps in a loop iteration manner until the updated finite element model of the structure reaches a preset constraint condition and a preset convergence condition, and output an optimized topological structure of the engineering structure.
Here, it should be noted that: the system 600 provided in the foregoing embodiment may implement the technical solutions described in the foregoing method embodiments, and the specific implementation principle of each module or unit may refer to the corresponding content in the foregoing method embodiments, which is not described herein again.
Based on the topology optimization method for improving the dynamic deletion rate, an embodiment of the present invention further provides an electronic device, including: a processor and a memory and a computer program stored in the memory and executable on the processor; the processor, when executing the computer program, implements the steps in the topology optimization method for improving dynamic deletion rate as described in the embodiments above.
A schematic structural diagram of an electronic device 700 suitable for implementing embodiments of the present invention is shown in fig. 7. The electronic devices in the embodiments of the present invention may include, but are not limited to, mobile terminals such as mobile phones, notebook computers, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), in-vehicle terminals (e.g., car navigation terminals), and the like, and fixed terminals such as digital TVs, desktop computers, and the like. The electronic device shown in fig. 7 is only an example, and should not bring any limitation to the functions and the scope of use of the embodiments of the present invention.
The electronic device includes: a memory and a processor, wherein the processor may be referred to as the processing device 701 hereinafter, and the memory may include at least one of a Read Only Memory (ROM) 702, a Random Access Memory (RAM) 703 and a storage device 708 hereinafter, as shown in detail below:
as shown in fig. 7, electronic device 700 may include a processing means (e.g., central processing unit, graphics processor, etc.) 701 that may perform various appropriate actions and processes in accordance with a program stored in a Read Only Memory (ROM) 702 or a program loaded from storage 708 into a Random Access Memory (RAM) 703. In the RAM703, various programs and data necessary for the operation of the electronic apparatus 700 are also stored. The processing device 701, the ROM702, and the RAM703 are connected to each other by a bus 704. An input/output (I/O) interface 705 is also connected to bus 704.
Generally, the following devices may be connected to the I/O interface 705: input devices 706 including, for example, a touch screen, touch pad, keyboard, mouse, camera, microphone, accelerometer, gyroscope, etc.; an output device 707 including, for example, a Liquid Crystal Display (LCD), a speaker, a vibrator, and the like; storage 708 including, for example, magnetic tape, hard disk, etc.; and a communication device 709. The communication means 709 may allow the electronic device 700 to communicate with other devices, wireless or wired, to exchange data. While fig. 7 illustrates an electronic device 700 having various means, it is to be understood that not all illustrated means are required to be implemented or provided. More or fewer devices may be alternatively implemented or provided.
In particular, according to an embodiment of the present invention, the processes described above with reference to the flowcharts may be implemented as computer software programs. For example, an embodiment of the invention includes a computer program product comprising a computer program carried on a non-transitory computer readable medium, the computer program containing program code for performing the method illustrated by the flow chart. In such an embodiment, the computer program may be downloaded and installed from a network via the communication means 709, or may be installed from the storage means 708, or may be installed from the ROM 702. The computer program, when executed by the processing device 701, performs the above-described functions defined in the methods of embodiments of the present invention.
Based on the topology optimization method for improving dynamic deletion rate, embodiments of the present invention also provide a computer-readable storage medium, where one or more programs are stored, and the one or more programs are executable by one or more processors to implement the steps in the topology optimization method for improving dynamic deletion rate according to the embodiments.
Those skilled in the art will appreciate that all or part of the flow of the method implementing the above embodiments may be implemented by a computer program, which is stored in a computer readable storage medium, to instruct related hardware. The computer readable storage medium is a magnetic disk, an optical disk, a read-only memory or a random access memory.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.
Claims (9)
1. A topology optimization method for improving dynamic deletion rate is applied to a structure optimization design process, and is characterized by comprising the following steps:
establishing an initial structure finite element model and a structure topological optimization mathematical model based on an engineering structure, allocating initial unit state variable values to each unit in the initial structure finite element model, and determining topological optimization related parameters for improving dynamic deletion rate, wherein the topological optimization related parameters for improving dynamic deletion rate comprise minimum deletion rateAnd an upper limit of increase in deletion rate;
Carrying out finite element solution on the initial structure finite element model to obtain element sensitivityDegree of structural stress uniformityStructural volume fraction indexAnd a firstStep dynamic deletion rateAccording to said secondStep dynamic deletion rateCalculate the firstVolume of step structure;
According to the said firstVolume of step structureSolving for sensitivity thresholdAnd according to the cell sensitivityAnd the sensitivity thresholdUpdating the initial structure finite element model;
whereinis a firstThe von Mises stress of the individual cells,the stress mean value of von Mises of all entity units in the current iteration step;
indexing the volume fraction of the structure by means of relative difference quotientAnd (3) solving:whereinfor the current number of iteration steps,is as followsThe volume of the step structure is increased,in order to optimize the target volume,to design domain volume;
based on the structural stress uniformityAnd structural volume fraction indexFor the second step, by means of a sine functionSolving the step dynamic deletion rate:;
and circularly and iteratively executing the solving and updating steps until the updated structure finite element model reaches a preset constraint condition and a preset convergence condition, and outputting the optimized topological structure of the engineering structure.
2. The method of claim 1, wherein the structural topology optimization mathematical model comprises:
whereinin order to have an average flexibility of the structure,andrespectively, the load and the unit displacement vector,in order to transpose the symbols,in order to be a constraint condition, the method comprises the following steps of,in order to optimize the target volume,is the total number of the entity units,is as followsThe volume of each unit cell is equal to the volume of each unit cell,is as followsThe state variable of each unit is changed into a state variable,representsThe unit is a physical unit which is a unit,representsThe unit is an empty unit;
the assigning of the initial element state variable value to each element in the initial structure finite element model includes the initial element of each element in the initial structure finite element model being a solid element.
5. the method of claim 4, wherein the cell sensitivity is based on the cell sensitivityAnd the sensitivity thresholdOptimizing the initial structure finite element model in terms of size, comprising:
when the cell sensitivity of any cellGreater than the sensitivity thresholdIf so, converting the unit into an entity unit;
6. The method according to claim 5, wherein the preset constraint condition comprises: the structure volume reaches the optimized target volume;
7. A topology optimization system for improving dynamic deletion rate is applied to a structure optimization design process, and is characterized by comprising the following steps:
the establishing module is used for establishing an initial structure finite element model and a structure topological optimization mathematical model based on an engineering structure, allocating initial unit state variable values to each unit in the initial structure finite element model and determining topological optimization related parameters for improving the dynamic deletion rate, wherein the topological optimization related parameters for improving the dynamic deletion rate comprise the minimum deletion rateAnd an upper limit of increase of deletion rate;
A solving module for carrying out finite element solution on the initial structure finite element model to obtain element sensitivityStructural stress uniformityStructural volume fraction indexAnd a first step ofStep dynamic deletion rateAccording to said secondStep dynamic deletion rateCalculate the firstVolume of step structure;
An update module for updating the first data according to the second dataVolume of step structureSolving for sensitivity thresholdAnd according to the cell sensitivityAnd the sensitivity thresholdUpdating the initial structure finite element model;
the degree of uniformity of the structural stress by using the coefficient of variationAnd (3) solving:whereinis as followsThe von Mises stress of the individual cells,the stress mean value of von Mises of all entity units in the current iteration step;
indexing the volume fraction of the structure by means of relative difference quotientAnd (3) solving:whereinfor the current number of iteration steps,is as followsThe volume of the step structure is increased,in order to optimize the target volume,to design domain volume;
based on the structural stress uniformityAnd structural volume fraction indexFor the second step, by means of a sine functionSolving the step dynamic deletion rate:;
and the output module is used for circularly and iteratively executing the solving and updating steps until the updated structure finite element model reaches a preset constraint condition and a preset convergence condition, and outputting the optimized topological structure of the engineering structure.
8. An electronic device comprising a memory and a processor, wherein the memory is configured to store a program; the processor, coupled to the memory, is configured to execute the program stored in the memory to implement the steps in the topology optimization method for improving dynamic deletion rate of any of the above claims 1 to 6.
9. A computer-readable storage medium storing a computer-readable program or instructions, which when executed by a processor, implement the steps of the topology optimization method for improving dynamic deletion rate according to any of the claims 1 to 6.
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109299519A (en) * | 2018-08-29 | 2019-02-01 | 湖南科技大学 | A kind of method of concrete component topology strut and tie adding window progressive structure optimization |
CN110069800A (en) * | 2018-11-17 | 2019-07-30 | 华中科技大学 | Three-dimensional structure method of topological optimization design and equipment with smooth boundary expression |
CN110348102A (en) * | 2019-07-04 | 2019-10-18 | 广州大学 | Dynamic evolution rate BESO Topology Optimization Method and its application based on arc tangent |
CN111353246A (en) * | 2020-02-28 | 2020-06-30 | 湖南科技大学 | Static and dynamic force multi-target topology evolution method for concrete member design |
CN111737839A (en) * | 2020-05-19 | 2020-10-02 | 广州大学 | BESO (beam-based event optimization) topology optimization method based on dynamic evolution rate and adaptive grid and application thereof |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI519987B (en) * | 2014-11-14 | 2016-02-01 | 財團法人工業技術研究院 | Structural topology optimization design method |
-
2022
- 2022-03-31 CN CN202210332696.2A patent/CN114417680B/en active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109299519A (en) * | 2018-08-29 | 2019-02-01 | 湖南科技大学 | A kind of method of concrete component topology strut and tie adding window progressive structure optimization |
CN110069800A (en) * | 2018-11-17 | 2019-07-30 | 华中科技大学 | Three-dimensional structure method of topological optimization design and equipment with smooth boundary expression |
CN110348102A (en) * | 2019-07-04 | 2019-10-18 | 广州大学 | Dynamic evolution rate BESO Topology Optimization Method and its application based on arc tangent |
CN111353246A (en) * | 2020-02-28 | 2020-06-30 | 湖南科技大学 | Static and dynamic force multi-target topology evolution method for concrete member design |
CN111737839A (en) * | 2020-05-19 | 2020-10-02 | 广州大学 | BESO (beam-based event optimization) topology optimization method based on dynamic evolution rate and adaptive grid and application thereof |
Non-Patent Citations (5)
Title |
---|
creep model of high-strength high-performance concrete under cyclic loading;Li, Q., Liu, M., Lu, Z. et al.;《 Wuhan Univ. Technol.-Mat. Sci. Edit》;20191231;622–629 * |
一种变删除率的渐进结构优化方法;李旭宇等;《长沙理工大学学报(自然科学版)》;20130628;第10卷(第02期);57-62、81 * |
加窗渐进结构优化算法;王磊佳等;《应用力学学报》;20181015;第35卷(第05期);1037-1044 * |
卢志芳 ; 黎子童 ; 刘沐宇 ; 刘齐民 ; 张强.基于正交试验新型钢-混组合板梁桥结构参数优化.《武汉理工大学学报》.2020, * |
基于一种动态删除率的ESO方法;罗静等;《计算力学学报》;20150415;第32卷(第02期);274-279 * |
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