Reliability-based structural optimization of frame structures for multiple failure criteria using topology optimization techniques

2006 ◽  
Vol 32 (4) ◽  
pp. 299-311 ◽  
Author(s):  
Katsuya Mogami ◽  
Shinji Nishiwaki ◽  
Kazuhiro Izui ◽  
Masataka Yoshimura ◽  
Nozomu Kogiso
Author(s):  
Manas Metar

Abstract: Weight reduction techniques have been practiced by automobile manufacturers for the purpose of long range, less fuel consumption and achieving higher speeds. Due to the numerous set objectives that must be met, especially with respect to of car safety, automotive chassis design for vehicle weight reduction is a difficult task. In passenger classed vehicles using a monocoque chassis for vehicle construction has been a great solution for reducing overall wight of the vehicle body yet the structure is more stiffened and sturdier. However, some parts such as A-pillar, B-pillar, roof structure, floor pan can be further optimized to reduce more weight without affecting the strength needed for respective purposes. In this paper, the main focus is on reducing weight of the B-pillar. The B-pillar of a passenger car has been optimized using topology optimization and optimum weight reduction has been done. The modelling and simulation are done using SOLIDWORKS 3D software. The B-pillar in this study has been subjected to a static load of 140 KN. Further by providing goals and constraints the optimization was caried out. The results of Finite Element Analysis (FEA) of the original model are explained. The Topology Optimization resulted in reducing 53% of the original weight of the B-pillar. Keywords: Structural optimization techniques, weight reduction techniques, weight reduction technologies, need for weight reduction, Topology optimization, B-pillar design, structural optimization of B-pillar, Topology optimization of B-pillar.


2011 ◽  
Vol 383-390 ◽  
pp. 5441-5446
Author(s):  
Chao Yan Wan ◽  
Xiao Feng Li ◽  
Jun Yong Li ◽  
Ying Liu

To achieve the damping design of an EMU bogie, the dynamic topology optimization is performed to the ATP hanging beam of bogie. Based on the HyperWorks / OptiStruct platform,the static and modal analyses on ATP are realized with the help of the finite element method. Then, the dynamic topology optimization is carried out in which improving the first natural frequency by variable density method is the optimization objective and the volume fraction and stress are the constraints. This optimization improves the structure and increases the natural frequency of the hanging beam. The design requirements are therefore satisfied. With the rapid development of high speed intercity rail, it's time to solve the security risk problem of trains. Using as the key components of high-speed bogie, more reasonable, safer and more reliable structure of ATP (Automatic Train Protection) hanging beam is needed by means of structural optimization, since it can improve the natural frequency of structure and increase the life of hanging beam on the hypothesis of meeting the fatigue strength conditions. Structural optimization design is a modern design manner combining the optimization techniques with the finite element analysis technology. In accordance with the degree of difficulty, it can be divided into size optimization, geometry optimization and structural topology optimization. The structural optimization design is the most challenging area because of the complexity of theory and calculation [1]. With the development and progress of technology, the dynamic characteristics of topology optimization for structures (including the natural frequency, mode shape, damping and stiffness and mass distribution, etc.) are attracted more and more attention[2]. The research focus mainly concentrates on the engineering applications [3-6]. In this paper, the dynamic topology optimization to the ATP hanging beam on a bogie is implemented by using the advanced structural optimization software named HyperWorks based on HyperWorks / OptiStruct platform [7]. An effective improvement plan of the ATP hanging beam is also introduced.


2019 ◽  
Vol 78 ◽  
pp. 528-544 ◽  
Author(s):  
Baotong Li ◽  
Honglei Liu ◽  
Wenjun Su

2021 ◽  
Vol 26 (2) ◽  
pp. 34
Author(s):  
Isaac Gibert Martínez ◽  
Frederico Afonso ◽  
Simão Rodrigues ◽  
Fernando Lau

The objective of this work is to study the coupling of two efficient optimization techniques, Aerodynamic Shape Optimization (ASO) and Topology Optimization (TO), in 2D airfoils. To achieve such goal two open-source codes, SU2 and Calculix, are employed for ASO and TO, respectively, using the Sequential Least SQuares Programming (SLSQP) and the Bi-directional Evolutionary Structural Optimization (BESO) algorithms; the latter is well-known for allowing the addition of material in the TO which constitutes, as far as our knowledge, a novelty for this kind of application. These codes are linked by means of a script capable of reading the geometry and pressure distribution obtained from the ASO and defining the boundary conditions to be applied in the TO. The Free-Form Deformation technique is chosen for the definition of the design variables to be used in the ASO, while the densities of the inner elements are defined as design variables of the TO. As a test case, a widely used benchmark transonic airfoil, the RAE2822, is chosen here with an internal geometric constraint to simulate the wing-box of a transonic wing. First, the two optimization procedures are tested separately to gain insight and then are run in a sequential way for two test cases with available experimental data: (i) Mach 0.729 at α=2.31°; and (ii) Mach 0.730 at α=2.79°. In the ASO problem, the lift is fixed and the drag is minimized; while in the TO problem, compliance minimization is set as the objective for a prescribed volume fraction. Improvements in both aerodynamic and structural performance are found, as expected: the ASO reduced the total pressure on the airfoil surface in order to minimize drag, which resulted in lower stress values experienced by the structure.


2013 ◽  
Vol 785-786 ◽  
pp. 1258-1261
Author(s):  
In Pyo Cha ◽  
Hee Jae Shin ◽  
Neung Gu Lee ◽  
Lee Ku Kwac ◽  
Hong Gun Kim

Topology optimization and shape optimization of structural optimization techniques are applied to transport skate the lightweight. Skate properties by varying the design variables and minimize the maximum stress and strain in the normal operation, while reducing the volume of the objective function of optimal design and Skate the static strength of the constraints that should not degrade compared to the performance of the initial model. The skates were used in this study consists of the main frame, sub frame, roll, pin main frame only structural analysis and optimal design was performed using the finite element method. Simplified initial model set design area and it compared to SM45C, AA7075, CFRP, GFRP was using the topology optimization. Strength does not degrade compared to the initial model, decreased volume while minimizing the stress and strain results, the optimum design was achieved efficient lightweight.


2021 ◽  
pp. 1-31
Author(s):  
Lorenzo Pinelli ◽  
Andrea Amedei ◽  
Enrico Meli ◽  
Federico Vanti ◽  
Benedetta Romani ◽  
...  

Abstract The need for high performances is pushing the complexity of mechanical design at very high levels, especially for turbomachinery components. Structural topology optimization methods together with additive manufacturing techniques for high resistant alloys are considered very promising tools, but their potentialities have not been deeply investigated yet for critical rotating components like new-generation turbine blades. This research work proposes a methodology for the design, the optimization and the additive manufacturing of extremely stressed turbomachinery components like turbine blade-rows. The presented procedure pays particular attention to important aspects of the problems as fluid-structure interactions and fatigue of materials, going beyond the standard structural optimization approaches found in the literature. The numerical procedure shows robustness and efficiency, making the proposed methodology a good tool for rapid design and prototyping, and for reducing the design costs and the time-to-market typical of these mechanical elements. The procedure has been applied to a low-pressure turbine rotor to improve the aeromechanical behavior while keeping the aerodynamic performance. From the original geometry, mode-shapes, forcing functions and aerodynamic damping have been numerically evaluated and are used as input data for the following topological optimization. Finally, the optimized geometry has been verified in order to confirm the improved aeromechanical design. After the structural topology optimization, the final geometries provided by the procedure have been then properly rendered to make them suitable for additive manufacturing. Some prototypes of the new optimized turbine blade have been manufactured to be tested in terms of fatigue.


Author(s):  
Ji-Hong Zhu ◽  
Wei-Hong Zhang

The purpose of this paper is to give an overall introduction of the structural optimization research works in ESAC group in 2011. Four main topics are involved, i.e. 1) topology optimization with multiphase materials, 2) integrated layout and topology optimization, 3) prediction of effective material properties and 4) composite design. More detailed techniques and some numerical results are also presented and discussed here.


2011 ◽  
Vol 267 ◽  
pp. 297-301
Author(s):  
Yong Wang ◽  
Guo Niu Zhu ◽  
Bo Yu Sun

The paper is concerned with topology optimization in the mechanical design process. The disadvantage of current process of mechanical design is discussed and a new design process based on structural topology optimization is presented. The design process with structural topology optimization in mechanical design is discussed by the example of the frame of a bender. Static analysis is made to the original model first according to the whole structure and working characteristic of the machine, the stress and deformation distribution are obtained and then topology optimization is carried out. On the basis of topology optimization, the layout of the initial design proposal is obtained and the weight of the frame is substantially reduced while the performance enhanced. The application of the method demonstrates that through innovative utilization of the topology optimization techniques, the conceptual proposals can be obtained and the overall mechanical design process can be improved substantially in a cost effective manner.


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