scholarly journals Development of the Sequential Voids Creation Approach in Axisymmetric Forming Dies

2021 ◽  
Vol 2096 (1) ◽  
pp. 012116
Author(s):  
I K Andrianov
Keyword(s):  
Elastic Modulus ◽  
Fatigue Strength ◽  
Stress State ◽  
Metal Forming ◽  
State Level ◽  
Optimization Methods ◽  
Optimization Method ◽  
Topological Optimization ◽  
Optimal Topology ◽  
Strength Curve

Abstract The study deals with the problem of topological optimization of forming dies with a limitation on fatigue strength. As a model of a stamp, a typical geometric configuration of stamps for the manufacture of parts of the " cup " type is considered. The algorithm for finding the optimal topology is proposed to be built separately in the internal areas under the stamp flanges and under the bottom of the "cup" of forming. Mathematical regularities are presented, according to which elements that fall into the area of predicted removal have a very small elastic modulus, which is widely used in topological optimization methods, then the stress state level is analyzed according to the fatigue strength curve. In the area of the flanges, there is a "build-up" of the mass according to the quadratic law with a variation in the depth of removal of the material. In the area of the bottom of the " cup " of forming, a step-by-step addition of rod elements is proposed until the level of the stress state meets the specified restrictions. Thus, this study is a modification of the topological optimization method. The novelty of the research lies in the construction of a new geometric scheme for determining the area of stored and deleted elements. The results of the study can be further developed in the development of methods for effective redistribution of material, as well as significantly reduce the material costs for the production of metal forming dies.

Finite Element Calculation of the Polymer Stamp Material Redistribution under Restrictions on Fatigue Life

2022 ◽  
Vol 1049 ◽  
pp. 248-254
Author(s):  
Ivan Andrianov
Keyword(s):  
Finite Element ◽  
Fatigue Strength ◽  
Stress State ◽  
Geometric Model ◽  
Optimization Methods ◽  
Optimization Method ◽  
Topological Optimization ◽  
Optimal Topology ◽  
Calculation Results ◽  
Rejection Coefficient

The numerical method of stamp topological optimization taking into account fatigue strength is presented in the work. It is proposed to take into account the restrictions on the stress state in accordance with the curve of the dependence of the maximum stresses on the number of loading cycles in the ESO topological optimization method. An approach to the selection of the evolutionary coefficient with a step-by-step increase in the rejection coefficient is proposed when constructing an iterative scheme for the rejection of elements by the method of topological optimization. The calculation of the stamp optimal topology with a decrease in volume due to the removal and redistribution of material was carried out in the study. The new geometric model of the optimal topology stamp is based on the predicted distribution of elements with a minimum stress level. The verification calculation of the stress state of the stamp of optimal topology with an assessment of fatigue strength was carried out in the work. The numerical calculation was carried out using the finite element method in the Ansys software package. The minimized stamp volume decreased by 35% according to the calculation results. The results of the study can be further applied in the development of topological optimization methods and in the design of stamping tools of optimal topology.

scholarly journals Topological Optimization of a Complex Shape Forming Stamp

2021 ◽  
Vol 2096 (1) ◽  
pp. 012115
Author(s):  
I K Andrianov
Keyword(s):  
Mathematical Modeling ◽  
Fatigue Strength ◽  
Stress State ◽  
Software Package ◽  
Complex Shape ◽  
Scientific Research ◽  
Topological Optimization ◽  
Optimal Topology ◽  
Ansys Software ◽  
Cold Stamping

Abstract The scientific research is devoted to the mathematical modeling of the optimal topology of stamps with a complex forming surface. Topological optimization is based on the SIMP method by creating a field of pseudo-densities and minimizing the pliability of the structure under the influence of load. When setting the problem, it is proposed to take into account the fatigue strength of polymers, taking into account the restrictions on the stress state. According to the results of the calculation in the ANSYS software package, an optimal redistribution of the stamp material and a reduction in volume due to the removal of elements that have little effect on the rigidity of the structure is obtained. The results of the study can be further applied in the field of hot and cold stamping by creating stamping tools of minimal volume.

Application of Topological Optimization on Aluminum Alloy Automobile Wheel Designing

2012 ◽  
Vol 562-564 ◽  
pp. 705-708
Author(s):  
Zhi Jun Zhang ◽  
Hong Lei Jia ◽  
Ji Yu Sun ◽  
Ming Ming Wang
Keyword(s):  
Topology Optimization ◽  
Lightweight Design ◽  
Optimization Method ◽  
Variable Density ◽  
Topological Optimization ◽  
Optimal Topology ◽  
Element Analysis ◽  
Material Interpolation ◽  
Strength And Stiffness

Topology optimization method based on variable density and the minimum compliance objective function was used on designing the wheel spokes. SIMP material interpolation model was established to compensate these deficiencies of variable density method. Considering manufacturing process and stress distribution, five bolt wheels was chose to topology optimization. The percentage of material removal of the optimal topology 40% was reasonable. Finite element analysis was used to test the strength and stiffness of the structure of the wheel, the result meets the requirements after wheel topology optimization, and reduces the quality of wheels to 7.76kg, achieve the goals of lightweight design.

Topological Optimization of Coronary Stents

2015 ◽  
Author(s):  
Shijia Zhao ◽  
Linxia Gu
Keyword(s):  
Radial Stress ◽  
Optimization Method ◽  
Homogenization Method ◽  
Topology Design ◽  
Topological Optimization ◽  
Optimal Topology ◽  
Patient Specific ◽  
Stent Design ◽  
Restenosis Rate ◽  
Radial Stiffness

The structural topological optimization method is an effective way to find the optimal topology of stents, which could be tailored for targeted stent performance, such as scaffolding ability, foreshortening, potential restenosis rate, etc. The radial stiffness is one of the major characteristics about stent performance. In this work, the homogenization method was utilized for the optimization of stent designs with the objective of maximizing the scaffolding ability of stent, i.e. its radial stiffness. A few design choices were presented by changing the number and distribution of strut connectors while keeping the void volume as 80%. The obtained optimal topology illustrated that the material distribution was mainly determined by the radial stress applied onto the stent. The optimal topology design in this work paves the way for the following dimension design, which can be targeted to the customized stent design for patient-specific lesions.

Application of Blank Optimization Method in Deep Drawing of Rectangular Magnesium Alloy Cups under Non-Isothermal Condition

2007 ◽  
Vol 344 ◽  
pp. 333-339
Author(s):  
W.T. Zheng ◽  
Donato Sorgente ◽  
G. Palumbo ◽  
Luigi Tricarico ◽  
Li Mei Ren ◽  
...  
Keyword(s):  
Magnesium Alloy ◽  
Deep Drawing ◽  
Metal Forming ◽  
Room Temperature ◽  
Isothermal Condition ◽  
Optimization Methods ◽  
Optimization Method ◽  
Forming Process ◽  
Metal Forming Process ◽  
Blank Shape

Using the optimum blank in sheet metal forming process not only can decrease the material wasting but also avoid possible defects such as local severe thinning, wrinkling and fracture. Since it is practical technology for industrial production, many blank optimization methods have been proposed and their validity was verified by some forming tests of typical or complicated components. However, all the forming tests were carried out at room temperature or under isothermal condition. In present work, a blank optimization method was employed to evaluate its efficiency in deep drawing of rectangular magnesium alloy cups under non-isothermal condition. It is proved by experiment that the employed blank optimization method can predict successfully the optimum initial blank shape for the component with specified shape and dimension.

scholarly journals Improvement of an additively manufactured subperiosteal implant structure design by finite elements based topological optimization

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alberto Carnicero ◽  
Andrés Peláez ◽  
Andrés Restoy-Lozano ◽  
Isaías Jacquott ◽  
Ricardo Perera
Keyword(s):  
Fatigue Strength ◽  
Structural Integrity ◽  
Optimization Methods ◽  
Structure Design ◽  
Biocompatible Materials ◽  
Topological Optimization ◽  
Manufacturing Cost ◽  
Surgical Trauma ◽  
Edentulous Patients ◽  
Subperiosteal Implant

AbstractTo design a new subperiosteal implant structure for patients suffering from severe Maxillary Atrophy that lowers manufacturing cost, shortens surgical time and reduces patient trauma with regard to current implant structures. A 2-phase finite-element-based topology optimization process was employed with implants made from biocompatible materials via additive manufacturing. Five bite loading cases related to standard chewing, critical chewing force, and worst conditions of fastening were considered along with each specific result to establish the areas that needed to be subjected to fatigue strength optimization. The 2-phase topological optimization tested in this study performed better than the reference implant geometry in terms of both the structural integrity of the implant under tensile-compressive and fatigue strength conditions and the material constraints related to implant manufacturing conditions. It returns a nearly 28% lower volumetric geometry and avoids the need to use two upper fastening screws that are required with complex surgical procedures. The combination of topological optimization methods with the flexibility afforded by additively manufactured biocompatible materials, provides promising results in terms of cost reduction, minimizing the surgical trauma and implant installation impact on edentulous patients.

3-D optimal design of laminated yoke of billet heater for rolling wire rod using ON/OFF method

2012 ◽  
Vol 61 (1) ◽  
pp. 115-123 ◽  
Author(s):  
Norio Takahashi ◽  
Shunsuke Nakazaki ◽  
Daisuke Miyagi ◽  
Naoki Uchida ◽  
Keiji Kawanaka ◽  
...  
Keyword(s):  
Optimal Design ◽  
Local Heating ◽  
Optimization Method ◽  
Optimal Topology ◽  
Field Problem ◽  
Heating Efficiency ◽  
Magnetic Devices ◽  
Wire Rod ◽  
Magnetic Recording Heads ◽  
Sensitivity Method

3-D optimal design of laminated yoke of billet heater for rolling wire rod using ON/OFF method The optimization method using the ON/OFF sensitivity analysis has an advantage that an epoch-making construction of magnetic circuit may be obtained. Therefore, it is attractive for designers of magnetic devices. We have already developed the ON/OFF method for the optimization of a static magnetic field problem, and the effectiveness is verified by applying it to the optimization of magnetic recording heads. In this paper, the ON/OFF sensitivity method is extended to the optimization of the eddy current problem using the adjoint variable. The newly developed ON/OFF method is applied to the determination of the optimal topology of the yoke of the billet heater for rolling wire rod. As a result, the optimal shape of yoke, which we could not imagine beforehand can be obtained. It is shown that the local heating of the yoke was reduced without decreasing the heating efficiency.

Reverse Modeling and Topological Optimization for Lightweight Design of Automobile Wheel Hubs with Hollow Ribs

2019 ◽  
Vol 17 (09) ◽  
pp. 1950064
Author(s):  
P. F. Xu ◽  
S. Y. Duan ◽  
F. Wang
Keyword(s):  
Finite Element ◽  
Lightweight Design ◽  
Element Model ◽  
Optimization Method ◽  
Modeling Technique ◽  
Topological Optimization ◽  
Time Interval ◽  
Braking Performance ◽  
Existing Structures ◽  
Physical Conditions

Lightweight of wheel hubs is the linchpin for reducing the unsprung mass and improving the vehicle dynamic and braking performance of vehicles, thus, sustaining stability and comfortability. Current experience-based lightweight designs of wheel hubs have been argued to render uneven distribution of materials. This work develops a novel method to combine the reverse modeling technique with the topological optimization method to derive lightweight wheel hubs based on the principles of mechanics. A reverse modeling technique is first adopted to scan and reproduce the prototype 3D geometry of the wheel hub with solid ribs. The finite element method (FEM) is then applied to perform stress analysis to identify the maximum stress and its location of wheel hub under variable potential physical conditions. The finite element model is then divided into optimization region and nonoptimized region: the former is the interior portion of spoke and the latter is the outer surface of the spoke. A topology optimization is then conducted to remove the optimization region which is interior material of the spokes. The hollow wheel hub is then reconstructed with constant wall thickness about 5[Formula: see text]mm via a reverse modeling technique. The results show that the reconstructed model can reduce the mass of 12.7% compared to the pre-optimized model. The present method of this paper can guarantee the optimal distribution of wheel hub material based on mechanics principle. It can be implemented automatically to shorten the time interval for optimal lightweight designs. It is especially preferable for many existing structures and components as it maintains the structural appearance of optimization object.

scholarly journals Strut-and-tie models for linear and nonlinear behavior of concrete based on topological evolutionary structure optimization (ESO)

2019 ◽  
Vol 12 (1) ◽  
pp. 87-100
Author(s):  
R. M. LANES ◽  
M. GRECO ◽  
M. B. B. F. GUERRA
Keyword(s):  
Nonlinear Behavior ◽  
Structure Optimization ◽  
Internal Flow ◽  
Optimization Method ◽  
Topological Optimization ◽  
Structural Elements ◽  
Stress Concentrations ◽  
Progressive Reduction ◽  
Strut And Tie ◽  
Safety And Reliability

Abstract The search for representative resistant systems for a concrete structure requires deep knowledge about its mechanical behavior. Strut-and-tie models are classic analysis procedures to the design of reinforced concrete regions where there are stress concentrations, the so-called discontinuous regions of the structure. However, this model is strongly dependent of designer’s experience regarding the compatibility between the internal flow of loads, the material’s behavior, the geometry and boundary conditions. In this context, the present work has the objective of presenting the application of the strut-and-tie method in linear and non-linear on some typical structural elements, using the Evolutionary Topological Optimization Method (ESO). This optimization method considers the progressive reduction of stiffness with the removal of elements with low values of stresses. The equivalent truss system resulting from the analysis may provide greater safety and reliability.

scholarly journals Target Localization Based on Bistatic T/R Pair Selection in GNSS-Based Multistatic Radar System

2021 ◽  
Vol 13 (4) ◽  
pp. 707
Author(s):  
Yu’e Shao ◽  
Hui Ma ◽  
Shenghua Zhou ◽  
Xue Wang ◽  
Michail Antoniou ◽  
...  
Keyword(s):  
Optimization Methods ◽  
Optimization Method ◽  
Satellite System ◽  
Radar System ◽  
Target Localization ◽  
Computational Load ◽  
Matrix Fusion ◽  
Global Navigation Satellite ◽  
Multistatic Radar ◽  
Combined Algorithm

To cope with the increasingly complex electromagnetic environment, multistatic radar systems, especially the passive multistatic radar, are becoming a trend of future radar development due to their advantages in anti-electronic jam, anti-destruction properties, and no electromagnetic pollution. However, one problem with this multi-source network is that it brings a huge amount of information and leads to considerable computational load. Aiming at the problem, this paper introduces the idea of selecting external illuminators in the multistatic passive radar system. Its essence is to optimize the configuration of multistatic T/R pairs. Based on this, this paper respectively proposes two multi-source optimization algorithms from the perspective of resolution unit and resolution capability, the Covariance Matrix Fusion Method and Convex Hull Optimization Method, and then uses a Global Navigation Satellite System (GNSS) as an external illuminator to verify the algorithms. The experimental results show that the two optimization methods significantly improve the accuracy of multistatic positioning, and obtain a more reasonable use of system resources. To evaluate the algorithm performance under large number of transmitting/receiving stations, further simulation was conducted, in which a combination of the two algorithms were applied and the combined algorithm has shown its effectiveness in minimize the computational load and retain the target localization precision at the same time.

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