Structure Topology Optimization Design Research Articles

Recent Advances on Topology Optimization of Multiscale Nonlinear Structures

Research on topology optimization mainly deals with the design of monoscale structures, which are usually made of homogeneous materials. Recent advances of multiscale structural modeling enables the consideration of microscale material heterogeneities and constituent nonlinearities when assessing the macroscale structural performance. However, due to the modeling complexity and the expensive computing requirement of multiscale modeling, there has been very limited research on topology optimization of multiscale nonlinear structures. This paper reviews firstly recent advances made by the authors on topology optimization of multiscale nonlinear structures, in particular techniques regarding to nonlinear topology optimization and computational homogenization (also known as FE2) are summarized. Then the conventional concurrent material and structure topology optimization design approaches are reviewed and compared with a recently proposed FE2-based design approach, which treats the microscale topology optimization process integrally as a generalized nonlinear constitutive behavior. In addition, discussions on the use of model reduction techniques is provided in regard to the prohibitive computational cost.

Topology Optimization Using Node-Based Smoothed Finite Element Method

The node-based smoothed finite element method (NS-FEM) proposed recently has shown very good properties in solid mechanics, such as providing much better gradient solutions. In this paper, the topology optimization design of the continuum structures under static load is formulated on the basis of NS-FEM. As the node-based smoothing domain is the sub-unit of assembling stiffness matrix in the NS-FEM, the relative density of node-based smoothing domains serves as design variables. In this formulation, the compliance minimization is considered as an objective function, and the topology optimization model is developed using the solid isotropic material with penalization (SIMP) interpolation scheme. The topology optimization problem is then solved by the optimality criteria (OC) method. Finally, the feasibility and efficiency of the proposed method are illustrated with both 2D and 3D examples that are widely used in the topology optimization design.

Topology Optimization Design of Spacecraft Antenna Pedestal Structure under Random Excitations

The purpose of this paper is to demonstrate a topology optimization design of the spacecraft antenna pedestal structure to save the structural weight as well as maintain the dynamic performances. The dynamic responses under random acceleration excitations are analyzed firstly and then the peaks of acceleration response are equaled to be static inertial load in the topology optimization as an expedient method. The pseudo-density based topology optimization model considering stress under inertial load as constraint is then formulated, and then further detailed design of the pedestal is carried out according to the optimized structural topology. Compared with the initial design, the optimized structure is improved with the total weight saved and both the dynamic responses and static stress satisfied.

Shape and Topology Optimization Design of Skeletal Structures using Metaheuristic Algorithms: A Review

Shape and Topology Optimization Design of Skeletal Structures using Metaheuristic Algorithms: A Review

Concurrent topology optimization design of material and structure within [formula omitted] nonlinear multiscale analysis framework

This paper revisits concurrent design of material and structure within FE2 nonlinear multiscale analysis framework. For structural stiffness maximization at macroscopic scale, design variables are defined at the both scales. Cellular material models are defined at microscopic scale in a pointwise manner for the considered macroscopic structure. They are optimized to adapt the macroscopic structural physical response. Though linear models are assumed at both scales, the macroscopic structural equilibrium is in general nonlinear due to the adaptation of cellular material microstructures. For this reason, an iterative resolution based on FE2 scheme is developed to address this nonlinearity. Discrete topology optimization algorithm, bi-directional evolutionary structural optimization (BESO) is used at the both scales. It is shown by means of numerical tests that FE2 scheme can well bridge the two scales and address the nonlinearity. Reasonable design solutions of the macroscopic structure and its corresponding cellular materials have been obtained by the developed concurrent design framework.

Topology Optimization Design of Pre-Stressed Plane Entity Steel Structure with the Constrains of Stress and Displacement

For the prestressed plane entitiy steel structure topology optimization design which design variables include the cable pretension value, unit size and the structural topology, the optimized mathematical model which objective function is the minimum structural weight is established with consideration of the constrains of stress and displacement. As for the solving method, firstly we need to determine the pretension applying to the cable according to full stress design and choose the unit size; then we need to conduct displacement sensitivity analysis to delete the low sensitivity unit to realize the structural topology optimization design. The example result is in conformity with the corresponding system of mechanical performance, and it indicates that the method proposed in this paper is effective.

Centrifugal stress analysis and structure optimization of large and high-speed end milling cutter

In the high-speed milling process of large end milling cutter, the stress of cutter caused by centrifugal force accounts for a large proportion of the total stress of the cutter and has a great influence on the milling process. In this paper, an end milling cutter with a diameter of 2,800 mm used on large and high-speed aluminum blank milling machine tools is taken as a research object, and the equations of internal stress caused by centrifugal force have been derived by using analytic method. On this basis, the factors affecting the internal stress were analyzed. Furthermore, the analytic results and the finite element analysis results were compared in order to confirm their correctness. Finally, according to the results of stress analysis, structure topology optimization design for large end milling cutter was carried out in order to reduce the weight and centrifugal force of the cutter.

A Wing Structure Design Based on Topology Optimization

Introduces the characteristics of topology optimization and bionics, proposes the steps and method of using MSC.Patran to establish the model of the wing structure topology optimization, and through to illustrate the feasibility of the method and the application value of the wing structure topology optimization and bionics design. Key words: topological optimization; wing structure; bionics design ;finite element; MSC Patran;MSC Nastran

Structure Topology Optimization Design for Compression Box of Horizontal Preloading Domestic Waste Transfer Station

Horizontal preloading domestic waste transfer station is the core equipment for domestic waste disposal. Compression equipment is the elementary equipment of horizontal preloading domestic waste transfer station, which should be ensured its mechanical properties and structural lightweight. According to the compression box structure in this paper, structural topology optimization model is established. By using HyperWorks software, the result of structural topology optimization result of compression box is obtained. Based on the result of topology optimization, the structural improvement design model of compression box is established, and the number, location, size of strengthening rib for bottom plate, top plate, side plate are optimal designed so as to realize structural lightweight.

Topology Optimization Design of Bars Structure Based on SKO Method

There are less topology optimization methods for bars structure than those for continuum structure. Bionic intelligent method is a powerful way to solve the topology optimization problems of bars structure since it is of good global optimization capacity and convenient for numerical calculation. This article presents a SKO topology optimization model for bars structure based on SKO (Soft Kill Option) method derived from adaptive growth rules of trees, bones, etc. The model has been applied to solve the topology optimization problem of a space frame. It uses three optimization strategies, which are constant, decreasing and increasing material removed rate. The impact on the optimization processes and results of different strategies are discussed, and the validity of the proposed model is proved.

Optimization Design of Vehicle Frame Based on ANSYS

A special vehicle frame as the research object, its topology optimization mathematical model and its algorithm is established based on variable density method. Topology optimization method of continuum structures is applied to the frame structural design of this special vehicle using Optistruct solver. Take the least flexibility of frame as design goal; topology optimization design of frame structure was carried under the condition of flexure, torsion and flexure-torsion. New structural model of frame was determined according to results of topology optimization and engineering experience. The calculation of the stress, deformation and the volume for optimization results was conducted with ANSYS software, and compared with the data before optimization. The results showed that the safety performance of optimized frame improved, and the weight reduced.

Topology Optimization Design of High Pressure Storage Tank Structure

In this paper, based on ANSYS the topology optimization design for high pressure storage tank was studied by the means of the finite element structural analysis and optimization. the finite element model for optimization design was established. The design variables influence factors and rules on the optimization results are summarized. according to the calculation results the optimal design result for tank is determined considering the manufacturing and processing. The calculation results show that the method is effective in optimization design and provide the basis to further design high pressure tank.

Method of Continuum Structural Topology Optimization with Information Functional Materials Based on K Nearest Neighbor

The KNN method is extracted from the technique of pattern recognition for the continuum structure topology optimization design with information functional materials. Original design region is taken as initial sample space, and continuum structure's units are regarded as samples. Unit stress and displacement sensitivity are utilized as feature vector to describe sample, and the feature vectors' Euclidean distance is considered as the recognition standard to classify all the samples. One FEM package is utilized to process the entire optimization. Finally, the topology optimization result is obtained. Several examples are verified under different situations. The results indicate that the KNN method is feasible.

Heat Conduction Structural Topology Optimization Based on RAMP

Based on topology optimization techniques of structural mechanics, an effective method for solving the structural design problems of heat transfer is presented in this paper. The topology optimization model of heat conduction is then constructed and the corresponding Optimization Criteria based on density approach is inferred to solve the optimal heat conduction equation of temperature field. A Filtering technique is employed in density field to eliminate numerical instabilities in the process of topology optimization. Some numerical examples are presented to demonstrate the accuracy and the applicability of the present method, theory and algorithm. This research provides a new idea and an access to the structural topology optimization design of temperature field, and is of good engineering application value.

Non-probabilistic Reliability Based Topology Optimization Design of Two-material Structures

Using the convex model description and the quantified definition of the non-probabilistic reliability,topology optimization of two-material structures considering uncertainties in material properties,geometry and loads is studied.Based on the extended penalization scheme of relative density,a continuous minimax optimization problem,which satisfies the material volume constraint and the reliability requirement,is presented for finding the united distribution of two candidate materials.The minimax problem is solved in the sequential approximate programming manner by embedding a direct iterative formula and the method of moving asymptotes(MMA).The computation cost is thus greatly decreased since the original problem is transformed into a series of deterministic ones.Numerical examples show that system uncertainties may have considerable effects on the optimal united layout of two-material structures.The results prove that a powerful approach for the topology design of two-material structures is furnished by the proposed numerical technique.

Topology Optimization Design of Integral Structure of Woodworking Machine Tool

In accordance with integral structure of woodworking machine tool (WMT), this paper uses the method based on topology optimization design to establish the objective function, constraints, and convergence Criteria. In the meantime, some related factors of woodworking machine tool (WMT), such as economical efficiency, stability, and dynamic properties are taken into consideration. Moreover, through analyzing an instance, the validity of design method has been demonstrated.

Digital Manufacturing of Topology Optimization Designed Structure Based on Lever Set Function

Based on the lever set function and the augmented Lagrange multiplier method, the topology optimization design of structure was achieved and the final cloud data were saved in matrix. The trigonometric patch method was explored to approach the optimized level set surface and the boundary data extraction was realized by each ridge line parametric equation. Together with the standards of the digital manufacturing, the cloud data were sorted through programming and exported by complying with the data format of digital manufacturing. The Wire Electrical Discharge Machining was proposed here to achieve the manufacturing on G01 code, which was proved to be practical by NC Viewer. This process fulfilled the whole courses from topology optimization to digital manufacturing, which makes the foundation for the promotion and large-scale production of topology optimization in future.

A Finite Volume Meshless Local Petrov-Galerkin Method for Topology Optimization Design of the Continuum Structures

A Finite Volume Meshless Local Petrov-Galerkin Method for Topology Optimization Design of the Continuum Structures

Application of virtual laminated element in the topology optimization of structures

This paper presents the topology optimization design of structures composed of plane stress elements. The authors' proposed method of topology optimization by virtual laminated element is based on the Evolutionary Structural Optimization (ESO) method of linear elasticity, but dose not require formation of as many elements as the conventional ESO method. The presented method has the important feature of reforming the stiffness matrix in generating optimum topology. Calculation results showed that this algorithm is simple and effective and can be applied for topology optimization of structures.

Topology optimization design of continuum structures under stress and displacement constraints

Topology optimization design of continuum structures that can take account of stress and displacement constraints simultaneously is difficult to solve at present. The main obstacle lies in that, the explicit function expressions between topological variables and stress or displacement constraints can not be obtained using homogenization method or variable density method. Furthermore, large quantities of design variables in the problem make it hard to deal with by the formal mathematical programming approach. In this paper, a smooth model of topology optimization for continuum structures is established which has weight objective considering stress and displacement constraints based on the independent-continuous topological variable concept and mapping transformation method proposed by Sui Yunkang and Yang Deqing. Moreover, the approximate, explicit expressions are given between topological variables and stress or displacement constraints. The problem is well solved by using dual programming approach, and the proposed element deletion criterion implements the inversion of topology variables from the discrete to the continuous. Numerical examples verify the validity of proposed method.