A Header Design Method for Target Flow Distribution among Parallel Channels Based on Topology Optimization

This paper discusses a flexible design method of cell traps based on the topology optimization of fluidic flows. Being different from the traditional method, this method obtains the periodic layout of the cell traps according to the cell trapping requirements by proposing a topology optimization model. Additionally, it satisfies the cell trapping function by restricting the flow distribution while taking into account the overall energy dissipation of the flow field. The dependence on the experience of the designer is reduced when this method is used to design a cell trap with acceptable trapping performance. By comparing the influence of the changes of various parameters on the optimization results, the flexibility of the topology optimization method for cell trap structure optimization is verified. The capability of this design method is validated by several performed comparisons between the obtained layouts and optimized designs in the published literature.

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A Shape Optimization Method for Part Design Derived from the Buildability Restrictions of the Directed Energy Deposition Additive Manufacturing Process

Designs ◽

10.3390/designs4030019 ◽

2020 ◽

Vol 4 (3) ◽

pp. 19

Author(s):

Andreas K. Lianos ◽

Harry Bikas ◽

Panagiotis Stavropoulos

Keyword(s):

Topology Optimization ◽

Additive Manufacturing ◽

Energy Deposition ◽

Design Method ◽

Current Trend ◽

Internal Stresses ◽

Material Distribution ◽

Load Case ◽

Design Elements ◽

Industrial Sectors

The design methodologies and part shape algorithms for additive manufacturing (AM) are rapidly growing fields, proven to be of critical importance for the uptake of additive manufacturing of parts with enhanced performance in all major industrial sectors. The current trend for part design is a computationally driven approach where the parts are algorithmically morphed to meet the functional requirements with optimized performance in terms of material distribution. However, the manufacturability restrictions of AM processes are not considered at the primary design phases but at a later post-morphed stage of the part’s design. This paper proposes an AM design method to ensure: (1) optimized material distribution based on the load case and (2) the part’s manufacturability. The buildability restrictions from the direct energy deposition (DED) AM technology were used as input to the AM shaping algorithm to grant high AM manufacturability. The first step of this work was to define the term of AM manufacturability, its effect on AM production, and to propose a framework to estimate the quantified value of AM manufacturability for the given part design. Moreover, an AM design method is proposed, based on the developed internal stresses of the build volume for the load case. Stress tensors are used for the determination of the build orientation and as input for the part morphing. A top-down mesoscale geometric optimization is used to realize the AM part design. The DED Design for Additive Manufacturing (DfAM) rules are used to delimitate the morphing of the part, representing at the same time the freeform mindset of the AM technology. The morphed shape of the part is optimized in terms of topology and AM manufacturability. The topology optimization and AM manufacturability indicator (TMI) is introduced to screen the percentage of design elements that serve topology optimization and the ones that serve AM manufacturability. In the end, a case study for proof of concept is realized.

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Structural topology optimization of bridge girders in cable supported bridges

IABSE Conference, Kuala Lumpur 2018: Engineering the Developing World ◽

10.2749/kualalumpur.2018.0975 ◽

2018 ◽

Author(s):

Mads Baandrup ◽

Ole Sigmund ◽

Niels Aage

Keyword(s):

Topology Optimization ◽

Large Scale ◽

Design Method ◽

Optimization Method ◽

Bridge Girders ◽

Structural Topology ◽

Box Girders ◽

Box Girder ◽

Fine Mesh ◽

Further Development

This work applies a ultra large scale topology optimization method to study the optimal structure of bridge girders in cable supported bridges.The current classic orthotropic box girder designs are limited in further development and optimiza tion, and suffer from substantial fatigue issues. A great disadvantage of the orthotropic girder is the loads being carried one direction at a time, thus creating stress hot spots and fatigue problems. Hence, a new design concept has the potential to solve many of the limitations in the current state of-the-art.We present a design method based on ultra large scale topology optimization. The highly detailed structures and fine mesh-discretization permitted by ultra large scale topology optimization reveal new design features and previously unseen eff ects. The results demonstrate the potential of gener ating completely different design solutions for bridge girders in cable supported bridges, which dif fer significantly from the classic orthotropic box girders.The overall goal of the presented work is to identify new and innovative, but at the same time con structible and economically reasonable, solutions tobe implemented into the design of future cable supported bridges.

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Multiscale, thermomechanical topology optimization of self-supporting cellular structures for porous injection molds

Rapid Prototyping Journal ◽

10.1108/rpj-09-2017-0190 ◽

2019 ◽

Vol 25 (9) ◽

pp. 1482-1492

Author(s):

Tong Wu ◽

Andres Tovar

Keyword(s):

Topology Optimization ◽

Mechanical Performance ◽

Mechanical Load ◽

Design Method ◽

Three Dimensional ◽

Optimization Method ◽

Cellular Structures ◽

Injection Mold ◽

Computationally Efficient ◽

Content Type

Purpose This paper aims to establish a multiscale topology optimization method for the optimal design of non-periodic, self-supporting cellular structures subjected to thermo-mechanical loads. The result is a hierarchically complex design that is thermally efficient, mechanically stable and suitable for additive manufacturing (AM). Design/methodology/approach The proposed method seeks to maximize thermo-mechanical performance at the macroscale in a conceptual design while obtaining maximum shear modulus for each unit cell at the mesoscale. Then, the macroscale performance is re-estimated, and the mesoscale design is updated until the macroscale performance is satisfied. Findings A two-dimensional Messerschmitt Bolkow Bolhm (MBB) beam withstanding thermo-mechanical load is presented to illustrate the proposed design method. Furthermore, the method is implemented to optimize a three-dimensional injection mold, which is successfully prototyped using 420 stainless steel infiltrated with bronze. Originality/value By developing a computationally efficient and manufacturing friendly inverse homogenization approach, the novel multiscale design could generate porous molds which can save up to 30 per cent material compared to their solid counterpart without decreasing thermo-mechanical performance. Practical implications This study is a useful tool for the designer in molding industries to reduce the cost of the injection mold and take full advantage of AM.

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An Artificial Intelligence–Assisted Design Method for Topology Optimization without Pre-Optimized Training Data

Applied Sciences ◽

10.3390/app11199041 ◽

2021 ◽

Vol 11 (19) ◽

pp. 9041

Author(s):

Alex Halle ◽

Lucio Flavio Campanile ◽

Alexander Hasse

Keyword(s):

Topology Optimization ◽

Input Data ◽

Design Method ◽

Design Procedure ◽

Computational Effort ◽

Training Data ◽

Geometry Design ◽

Random Input Data ◽

Degree Of Filling ◽

Initial Process

Engineers widely use topology optimization during the initial process of product development to obtain a first possible geometry design. The state-of-the-art method is iterative calculation, which requires both time and computational power. This paper proposes an AI-assisted design method for topology optimization, which does not require any optimized data. An artificial neural network—the predictor—provides the designs on the basis of boundary conditions and degree of filling as input data. In the training phase, the so-called evaluators evaluate the generated geometries on the basis of random input data with respect to given criteria. The results of those evaluations flow into an objective function, which is minimized by adapting the predictor’s parameters. After training, the presented AI-assisted design procedure generates geometries that are similar to those of conventional topology optimizers, but require only a fraction of the computational effort. We believe that our work could be a clue for AI-based methods that require data that are difficult to compute or unavailable.

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The influences of variable sectional area design on improving the hydrocarbon fuel flow distribution in parallel channels under supercritical pressure

Fuel ◽

10.1016/j.fuel.2018.06.082 ◽

2018 ◽

Vol 233 ◽

pp. 442-453 ◽

Cited By ~ 4

Author(s):

Yuguang Jiang ◽

Jiang Qin ◽

Yaxing Xu ◽

Wenli Yu ◽

Silong Zhang ◽

...

Keyword(s):

Flow Distribution ◽

Hydrocarbon Fuel ◽

Supercritical Pressure ◽

Sectional Area ◽

Fuel Flow ◽

Parallel Channels

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Microstructural Topology Optimization of Constrained Layer Damping on Plates for Maximum Modal Loss Factor of Macrostructures

Shock and Vibration ◽

10.1155/2020/8837610 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Zhanpeng Fang ◽

Lei Yao ◽

Shuxia Tian ◽

Junjian Hou

Keyword(s):

Topology Optimization ◽

Loss Factor ◽

Strain Energy ◽

Design Method ◽

Optimization Method ◽

Constrained Layer Damping ◽

Viscoelastic Materials ◽

Modal Strain Energy ◽

Design Variables ◽

Microstructural Topology Optimization

This paper presents microstructural topology optimization of viscoelastic materials for the plates with constrained layer damping (CLD) treatments. The design objective is to maximize modal loss factor of macrostructures, which is obtained by using the Modal Strain Energy (MSE) method. The microstructure of the viscoelastic damping layer is composed of 3D periodic unit cells. The effective elastic properties of the unit cell are obtained through the strain energy-based method. The density-based topology optimization is adopted to find optimal microstructures of viscoelastic materials. The design sensitivities of modal loss factor with respect to the design variables are analyzed and the design variables are updated by Method of Moving Asymptotes (MMA). Numerical examples are given to demonstrate the validity of the proposed optimization method. The effectiveness of the optimal design method is illustrated by comparing a solid and an optimized cellular viscoelastic material as applied to the plates with CLD treatments.

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Layout Design of Stiffened Plates for Large-Scale Box Structure under Moving Loads Based on Topology Optimization

Mathematical Problems in Engineering ◽

10.1155/2020/8843657 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Zhaohua Wang ◽

Chenglong Yang ◽

Xiaopeng Xu ◽

Dezhuang Song ◽

Fenghe Wu

Keyword(s):

Topology Optimization ◽

Large Scale ◽

Load Transfer ◽

Comprehensive Evaluation ◽

Design Method ◽

Layout Design ◽

Stiffened Plates ◽

Moving Loads ◽

Box Structures ◽

Box Structure

As the main load-bearing structure of heavy machine tools, cranes, and other high-end equipment, the large-scale box structures usually bear moving loads, and the results of direct topology optimization usually have some problems: the load transfer skeleton is difficult to identify and all working conditions are difficult to consider comprehensively. In this paper, a layout design method of stiffened plates for the large-scale box structures under moving loads based on multiworking-condition topology optimization is proposed. Based on the equivalent principle of force, the box structures are simplified into the main bending functional section, main torsional functional section, and auxiliary functional section by the magnitude of loads and moments, which can reduce the structural dimension and complexity in topology optimization. Then, the moving loads are simplified to some multiple position loads, and the comprehensive evaluation function is constructed by the compromise programming method. The mathematical model of multiworking-condition topology optimization is established to optimize the functional sections. Taking a crossbeam of superheavy turning and milling machining center as an example, optimization results show that the stiffness and strength of the crossbeam are increased by 17.39% and 19.9%, respectively, while the weight is reduced by 12.57%. It shows that the method proposed in this paper has better practicability and effectiveness for large-scale box structures.

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Comparator Synthesis Using Distributed Genetic Algorithm and HSPICE Optimization

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.888.17 ◽

2019 ◽

Vol 888 ◽

pp. 17-28

Author(s):

Nobukazu Takai ◽

Kento Suzuki ◽

Yoshiki Sugawara

Keyword(s):

Genetic Algorithm ◽

Topology Optimization ◽

Design Method ◽

Automatic Design ◽

Circuit Topology ◽

Target Value ◽

Distributed Genetic Algorithm ◽

Better Than

In this paper, we propose an automatic design method that determines comparator topology and satisfies desired specification of the comparator by combining distributed genetic algorithm and HSPICE optimization function.In the comparator synthesis, new topology is created using known circuit topology information.After creating the topology, optimization of element values of the comparator is executed by distributed genetic algorithm and HSPICE optimization.As a target value example, specification of HA163S02 is used.Simulation results indicate that the proposed method can design the comparator despite the number of specifications and elements of circuit increase compared to the conventional methods.Furthermore, the performance of the automatic designed comparator is better than that of conventional comparators.

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Research on the Design Method of the Centrifugal Pump With Splitter Blades

Volume 1: Symposia, Parts A, B and C ◽

10.1115/fedsm2009-78101 ◽

2009 ◽

Cited By ~ 4

Author(s):

Shouqi Yuan ◽

Jinfeng Zhang ◽

Yue Tang ◽

Jianping Yuan ◽

Yuedeng Fu

Keyword(s):

Flow Field ◽

Centrifugal Pump ◽

Design Method ◽

Flow Distribution ◽

Orthogonal Test ◽

Operating Conditions ◽

Test Results ◽

Cfd Simulations ◽

Pump Performance ◽

Blade Number

The research on a centrifugal pump of low specific speed with splitter blades was carried out in recent years by our group, is systematically introduced in this paper. The design method is summarized also. At the beginning, based on the former L9(34) orthogonal test, Particle Imagine Velocity (PIV) tests and Computational Fluid Dynamics (CFD) simulations were carried out for several designs with different splitter blade length. Results show that for an impeller with splitter blades the “jet-wake” flow at the impeller outlet is improved, and the velocity distribution inside the impeller is more uniform. This explains that the impeller with splitter blades shows higher performance (especially in head and efficiency). Meanwhile, the numerical simulation results were compared with the test results, which confirm that, CFD technology can be used to observe inner flow distribution and forecast pump performance tendency. Later, a further L9(34) orthogonal test, which adopt the blade number as a new variable, was designed to explore the relationship between geometry parameters of splitter blade and pump performance, and corresponding CFD simulations for the flow field with volute were also done. From the test results the influence of the main design parameters on the hydraulic performance of a centrifugal pump and its reasonable value range are determined. The simulations forecasted pump performance show good consistency with that from tests at the rated point, and the simulated error at other flow rates were analyzed. Thirdly, in order to save research cost, numerical simulations were done for the full flow field including the cavity inside the volute and impeller. By analyzing the distribution law of blade torque and turbulent kinetic energy in the impeller, the value fetching principle for the splitter blade inlet diameter is presented as “the splitter blades torque should be positive”, and by analyzing the distribution of blades loading, the flow distribution rules and pump performance influenced by different splitter blades off-setting angles and inlet diameters were discovered. The disk friction loss, which consuming much energy in centrifugal pumps, was also forecasted at various operating conditions. The results were compared with that from empirical formulas, which show great accordance at the rated point, and the forecasted results at off-design points were analyzed also. Finally, the research results and the design method for the centrifugal pump with splitter blades, such as how to select splitter blade number, the off-setting angle, the inlet diameter and the deflection angle, were summarized.

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