A Novel Adaptive Topology Optimization Method Considering Unnecessary Element Removal and Progressive Mesh Refinement

2018 ◽  
Author(s):  
Yingchun Bai ◽  
Il Yong Kim ◽  
Cheng Lin
Keyword(s):  
Topology Optimization ◽  
Optimization Method ◽  
3D Design ◽  
Solution Quality ◽  
Design Problems ◽  
Progressive Mesh ◽  
Adaptive Topology ◽  
Optimization Efficiency ◽  
Element Removal ◽  
Density Threshold

This paper proposes an adaptive topology optimization (TO) approach considering unnecessary element removal and progressive element refinement. A two-stage density filtering for element removal is developed to relax the design space for next iteration, and therefore make a trade-off between solution quality and optimization efficiency. An isolated element detection and deletion is also conducted between element removal and element refinement operation to guarantee the numerical stability. Two 2D numerical examples and one 3D design problems are investigated to demonstrate the effectiveness of the proposed method. Based on the numerical tests, the applicability range of the proposed method and recommended range of element density threshold are provided as well.

Topology Optimization of Bracing Systems for Multistory Steel Frames under Earthquake Loads

2011 ◽  
Vol 255-260 ◽  
pp. 2388-2393 ◽  
Author(s):  
Ji Zhuo Huang ◽  
Zhan Wang
Keyword(s):  
Topology Optimization ◽  
Weighted Average ◽  
Optimization Method ◽  
Layout Design ◽  
Computational Effort ◽  
Steel Frame ◽  
Structural Topology Optimization ◽  
Structural Topology ◽  
Earthquake Loads ◽  
Element Removal

Application of continuum structural topology optimization methods to the layout design of bracing systems for multistory steel frame buildings under earthquake loads is explored in this work. A weighted average strain energy sensitivity of element is formulated to be served as the element removal criterion in the optimization process, and then an ESO-based continuum structural topology optimization method for the layout design of multistory steel frame bracing systems subjected to earthquake-induced ground motions is presented. In each iterative design, an approximate reanalysis technique named CA method is adopted to reduce the computational effort. Finally, a design example is given to demonstrate the effectiveness of the presented optimization method for the optimal layout design of steel frame bracing systems under earthquake loads.

A level set-based topology optimization method targeting metallic waveguide design problems

2011 ◽  
Vol 87 (9) ◽  
pp. 844-868 ◽  
Author(s):  
Shintaro Yamasaki ◽  
Tsuyoshi Nomura ◽  
Atsushi Kawamoto ◽  
Kazuo Sato ◽  
Shinji Nishiwaki
Keyword(s):  
Topology Optimization ◽  
Level Set ◽  
Optimization Method ◽  
Design Problems ◽  
Waveguide Design ◽  
Metallic Waveguide ◽  
Topology Optimization Method

Bi-Directional Evolutionary Structural Optimization Method with Draw Direction Constraints

2013 ◽  
Vol 420 ◽  
pp. 346-351
Author(s):  
Tien Tung Chung ◽  
Jia Pei Wang ◽  
Yan Zuo Chen ◽  
Ta Chuan Liu
Keyword(s):  
Structural Optimization ◽  
Mechanical Design ◽  
Optimization Method ◽  
Optimized Design ◽  
Design Problems ◽  
Closed Cavity ◽  
Evolutionary Structural Optimization ◽  
Draw Direction ◽  
Beso Method ◽  
Element Removal

This paper proposes a new bi-directional evolutionary structural optimization (BESO) method with draw direction constraints. Draw direction constraints, defined by required manufacturing process, are achieved by modifying element removal/addition criteria such that elements are removed from the top surface of the draw direction to the inner design domain. The optimized design with draw direction constraints is free from hollow or closed cavity geometries which are infeasible for manufacturing. A stiffness design of a motor front cover is carried out to show the ability of the proposed method in practical mechanical design problems.

Multi-material topology optimization for automotive design problems

2017 ◽  
Vol 232 (14) ◽  
pp. 1950-1969 ◽  
Author(s):  
Chao Li ◽  
Il Yong Kim
Keyword(s):  
Topology Optimization ◽  
Conceptual Design ◽  
Real World ◽  
Optimization Method ◽  
Design Problems ◽  
Multiple Load Cases ◽  
Engineering Problems ◽  
Single Material ◽  
Multiple Load ◽  
Topology Optimization Method

The algorithms for multi-material topology optimization were developed to solve compliance-minimization problems and applied to engineering problems in automotive concepts and lightweight design. Two small-scale problems of a long cantilever and a control arm were studied initially to verify the effectiveness of the developed algorithms and in-house program. Optimal solutions achieved by the multi-material topology optimization method developed were compared to their counterparts obtained by standard single-material topology optimization. To efficiently solve real-world engineering problems, the algorithms were further advanced to incorporate extrusion constraints and to handle multiple load cases. The effectiveness and the efficiency of the proposed method were demonstrated by the study of two real-world engineering problems: (a) the conceptual design of a cross-member for a chassis frame; and (b) the conceptual design of an automotive engine cradle. The two optimization design problems both involved complex geometries, design and non-design domains, prescribed regions with specific material allocations, multiple load cases, and manufacturing extrusion constraints. It was explicitly demonstrated that, for the same weight, the optimum designs achieved by the multi-material topology optimization method were stiffer than those achieved by standard single-material topology optimization.

Topology Optimization of Poroelastic Structures to Minimize Mean Sound Pressure Levels

2008 ◽  
Author(s):  
T. Yamamoto ◽  
S. Maruyama ◽  
S. Nishiwaki ◽  
M. Yoshimura
Keyword(s):  
Topology Optimization ◽  
Sound Pressure ◽  
Optimization Problems ◽  
Optimization Method ◽  
Biot’S Theory ◽  
Equivalent Representation ◽  
Design Problems ◽  
Biot's Theory ◽  
Sound Pressure Levels ◽  
Poroelastic Material

In optimization problems that aim to minimize noise, elastic structures have been designed so that fundamental eigenfrequencies depart from excitation frequencies. Moreover, for the sake of simplicity, sound pressure responses have rarely been calculated. In this paper, we propose a new topology optimization method for the design of poroelastic material layouts that minimize sound pressure levels by sound attenuation. In this method, the surrounding air is exactly modeled, and poroelastic material is located in a space filled with air to efficiently dissipate power. The Biot’s theory is incorporated into the optimization scheme to deal with poroelastic material, and we utilize a new bi-material continuum that consists of poroelastic material combined with an equivalent representation of air in the Biot’s theory. Several design problems are presented to demonstrate that the proposed method can provide optimal layouts of poroelastic material that reduce sound pressure levels within specified frequency ranges.

scholarly journals Topology Optimization of Hard-Coating Thin Plate for Maximizing Modal Loss Factors

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 774
Author(s):  
Haitao Luo ◽  
Rong Chen ◽  
Siwei Guo ◽  
Jia Fu
Keyword(s):  
Topology Optimization ◽  
Objective Function ◽  
Composite Plates ◽  
Optimization Method ◽  
Hard Coating ◽  
Design Variables ◽  
Coating Composite ◽  
Damping Materials ◽  
Topology Optimization Method ◽  
Loss Factors

At present, hard coating structures are widely studied as a new passive damping method. Generally, the hard coating material is completely covered on the surface of the thin-walled structure, but the local coverage cannot only achieve better vibration reduction effect, but also save the material and processing costs. In this paper, a topology optimization method for hard coated composite plates is proposed to maximize the modal loss factors. The finite element dynamic model of hard coating composite plate is established. The topology optimization model is established with the energy ratio of hard coating layer to base layer as the objective function and the amount of damping material as the constraint condition. The sensitivity expression of the objective function to the design variables is derived, and the iteration of the design variables is realized by the Method of Moving Asymptote (MMA). Several numerical examples are provided to demonstrate that this method can obtain the optimal layout of damping materials for hard coating composite plates. The results show that the damping materials are mainly distributed in the area where the stored modal strain energy is large, which is consistent with the traditional design method. Finally, based on the numerical results, the experimental study of local hard coating composites plate is carried out. The results show that the topology optimization method can significantly reduce the frequency response amplitude while reducing the amount of damping materials, which shows the feasibility and effectiveness of the method.

Sign in / Sign up

Export Citation Format

Share Document