Article
Mechanics
Yu Li, Jiemin Ding, Zheng Zhang, Xinjie Zhou, Mehdi Makvandi, Philip F. Yuan, Yi Min Xie
Summary: With the development of architectural design and structural analysis techniques, structural performance-based design approaches have gained importance in the field of architecture. This study introduces a multi-material topology optimization method and applies it to the core structure design of the Xiong'an Wings building project, achieving favorable results.
COMPOSITE STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Rossana R. Fernandes, Ali Y. Tamijani
Summary: This paper presents an experimentally validated framework for performing topology and orientation optimization of lattice structures subject to stress constraints. Effective stiffnesses and yield stresses of a unit cell are obtained using numerical homogenization and implemented via macrostructure topology optimization to improve lattice structure stiffness.
MATERIALS & DESIGN
(2021)
Article
Computer Science, Interdisciplinary Applications
Shuai Li, Yongcun Zhang, Shutian Liu, Shuhao Wu
Summary: This study presents a topology optimization method for thermoelastic structures under transient thermal loads, considering thermal stress constraints. The method can realize accurate optimization and effective stress control of transient thermoelastic structures. The temperature field and elastic responses are obtained by solving the transient thermal conductive equations and thermoelastic equations. The adjoint method is used to derive the sensitivity expressions. Three numerical examples are provided to illustrate the effectiveness and necessity of the proposed method. The results show that the adopted design method needs to accurately reflect the influence of transient effects on the structural response, which can be achieved by the method proposed in this paper.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2023)
Article
Engineering, Multidisciplinary
Saurav Dixit, Anna Stefanska, Adam Musiuk
Summary: This passage discusses the importance of the relationship between architectural and structural systems in sustainable design, as well as the method of minimizing material consumption through inspiration from nature. The research found that structural and architectural optimization implemented in the early stages of design can significantly reduce material consumption.
AIN SHAMS ENGINEERING JOURNAL
(2021)
Article
Computer Science, Interdisciplinary Applications
Quhao Li, Qiangbo Wu, Ji Liu, Jingjie He, Shutian Liu
Summary: This paper proposes a new formulation of frequency band constraint based on a modified Heaviside function for topology optimization of engineering structures. The method effectively addresses numerical issues in the optimization process and validates its effectiveness by considering frequency band constraints in optimized results.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2021)
Article
Computer Science, Interdisciplinary Applications
Ronald Bartz, Thilo Franke, Sierk Fiebig, Thomas Vietor
Summary: This paper presents a density-based shape optimization method using an interface motion scheme. The aim is to generate optimal material distributions with high-quality interfaces for topology and shape optimization. By using a density function, the method can seamlessly adopt density-based topology optimization results as the initial design, and also introduce a constraint for surface curvature.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2022)
Article
Computer Science, Interdisciplinary Applications
Chaitanya Dev, Gabriel Stankiewicz, Paul Steinmann
Summary: We propose a sequential topology and shape optimization framework for designing compliant mechanisms with boundary stress constraints. Our approach utilizes a density-based topology optimization method to generate the configuration of the mechanisms and a node-based shape optimization method for obtaining an exact boundary representation. Stress constraints are imposed to avoid impractical hinges with point connections, either locally on the nodes of the boundary or globally using P-norm stress constraints in the domain. Moreover, our method incorporates an adaptive shape refinement strategy to increase the design space and capture fine-scale geometry details. Numerical experiments demonstrate the effectiveness of our approach in designing compliant mechanisms with stress constraints.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2022)
Article
Computer Science, Interdisciplinary Applications
Alberto Donoso, Ernesto Aranda, David Ruiz
Summary: The aim of this work is to propose a continuous mathematical model that captures and enforces connectivity in topology optimization. This is achieved by constraining the second eigenvalue of an auxiliary eigenproblem solved alongside the governing state law during each iterative step. The effectiveness of our density-based approach is demonstrated through 2D and 3D numerical examples in the field of structural design.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2023)
Article
Computer Science, Interdisciplinary Applications
Xuan Wang, Hongliang Liu, Zhan Kang, Kai Long, Zeng Meng
Summary: This study tackles the minimum stress design problem in continuum structures with movable holes for the first time, proposing an effective hybrid methodology that optimizes material density and geometric parameters as design variables. By mapping embedded holes to a density field and introducing a new material interpolation scheme, the optimization model successfully minimizes stress in the system.
COMPUTERS & STRUCTURES
(2021)
Article
Computer Science, Interdisciplinary Applications
Gregoire Allaire, Martin Bihr, Beniamin Bogosel, Matias Godoy
Summary: This paper focuses on the accessibility constraint, a geometric constraint for shape and topology optimization of structures in additive manufacturing. The constraint is motivated by the difficulty in removing sacrificial supports hidden within complex geometries of structures. The paper presents a mathematical approach to evaluate this accessibility constraint using distance functions and eikonal equations, allowing for shape derivatives computation. Numerical demonstrations show that the approach enables simultaneous optimization of mechanical performance and accessibility of building supports, ensuring manufacturability.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Physics, Applied
Tyler W. Hughes, Momchil Minkov, Victor Liu, Zongfu Yu, Shanhui Fan
Summary: Metalenses for optical beam manipulation have a significant impact in many applications, but the large physical size relative to the optical wavelength poses a barrier to accurate simulations. Advances in computing hardware now make it feasible to simulate large area metalenses within a reasonable time frame, providing significant opportunities for the field.
APPLIED PHYSICS LETTERS
(2021)
Article
Engineering, Multidisciplinary
Weisheng Zhang, Qingqing Jiang, Weizhe Feng, Sung-Kie Youn, Xu Guo
Summary: This article presents an explicit topology optimization approach using the moving morphable void (MMV) based on the boundary element method. Compared to conventional methods, this approach uses B-splines to describe structural boundaries, avoids the use of weak materials, and enables precise and explicit description of voids to capture tiny structural features effectively. Additionally, it naturally avoids numerical instabilities that may arise from the use of fixed meshes.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2021)
Article
Engineering, Mechanical
Zeng Meng, Gang Yang, Qiangbo Wu, Shan Xiao, Quhao Li
Summary: Resonance can be avoided by preventing structural natural frequencies from falling within the operating frequency range. However, these frequencies are influenced by uncertain parameters. Therefore, a reliability-based eigenvalue topology optimization model is established to consider these uncertainties. To reduce computational burden, a frequency-band constraint shifting method (FBCSM) is proposed. Sensitivities of eigenfrequencies with respect to design and random variables are derived. Examples demonstrate the effectiveness and efficiency of the proposed model and FBCSM.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Wei Huang, Chongcong Tao, Hongli Ji, Jinhao Qiu
Summary: This work reports a simultaneous optimization of Acoustic Black Hole (ABH) plates for broadband energy dissipation. The geometry of the plate and the topology of the damping layer are optimized using a novel objective function. The achieved optimal arrangement of the damping layer covers more than just the ABH area, contradicting the conventional belief. The mechanism of broadband energy dissipation by the optimal solution is demonstrated.
JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Weisheng Zhang, Yue Wang, Zongliang Du, Chang Liu, Sung-Kie Youn, Xu Guo
Summary: A machine-learning assisted topology optimization approach is proposed for architectural design with artistic flavor. Neural style transfer technique is adopted to measure and generate prior knowledge from a reference image with concerned artistic flavor. The measured knowledge is integrated into pixel-based topology optimization as a formal similarity constraint. The effectiveness of the proposed approach is illustrated through solving 2D and 3D problems, achieving systematic inheritance of artistic heritage.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Review
Computer Science, Interdisciplinary Applications
Rebekka V. Woldseth, Niels Aage, J. Andreas Baerentzen, Ole Sigmund
Summary: The question of how artificial intelligence methods can improve traditional frameworks for topology optimization has gained attention in the past few years. While different model variations have been proposed with varying levels of success, few significant breakthroughs have been achieved. The literature tends to have a strong belief in the magical capabilities of artificial intelligence, leading to misunderstandings about its limitations. This article presents a critical review of the current state of research in this field and provides recommendations for future scientific progress.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2022)
Article
Chemistry, Multidisciplinary
Fengwen Wang, Marie Brons, Ole Sigmund
Summary: Stretch-dominated truss and plate microstructures are competing in the development of highly rigid and strong architected materials. Although closed-cell isotropic plate microstructures meet theoretical upper bounds on stiffness, they have low buckling strength, whereas open-cell truss microstructures have high buckling strength but reduced stiffness. Hollow truss lattice and hierarchical microstructures outperform both in terms of buckling strength, but are challenging to build. In this study, single-scale non-hierarchical microstructures are designed, built, and tested, surpassing the buckling strength of hollow truss lattice and plate microstructures. The microstructures are realized with 3D printing and both experiments and numerical modeling validate the theoretical predictions.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Optics
Rasmus E. Christiansen, Philip Trost Kristensen, Jesper Mork, Ole Sigmund
Summary: Using topology optimization, compact wavelength-sized devices are designed to study the effect of optimizing geometries for enhancing different optical processes. The findings show that different field distributions lead to maximization of different processes, emphasizing the importance of targeting the appropriate metric when designing photonic components for optimal performance.
Article
Engineering, Multidisciplinary
Yafeng Wang, Ole Sigmund
Summary: This study aims to optimize the buckling capacity of mechanical structures subjected to thermal and mechanical loading through a density-based topology optimization scheme. By decoupling the effects of mechanical and thermal loadings, the buckling aspects induced by each loading can be separately analyzed and optimized. The study also employs a multi-material topology optimization scheme to optimize the buckling capacity of active structures and prestressed structures.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Erik A. Traff, Anton Rydahl, Sven Karlsson, Ole Sigmund, Niels Aage
Summary: This work presents three-dimensional linear elastic compliance minimisation using topology optimisation implementations accelerated by Graphics Processing Units (GPUs). Two GPU-accelerated implementations, based on OpenMP 4.5 and the Futhark language, are presented. Both implementations utilize high level GPU frameworks, avoiding the need for expertise knowledge of CUDA or OpenCL. Additionally, a vectorised and multi-threaded CPU code is included for reference. The results show that the GPU accelerated codes are able to solve large-scale topology optimisation problems faster than the reference CPU code, and they can also handle nonlinear problems.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Christoffer Fyllgraf Christensen, Fengwen Wang, Ole Sigmund
Summary: Topology optimization has been used for maximizing stiffness or minimizing compliance in multiscale structures. This study focuses on optimizing buckling stability of multiscale structures with isotropic porous infill, by considering both local and global instability.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Federico Ferrari, Ole Sigmund
Summary: In this study, a strategy is introduced to prevent the occurrence of spurious modes in the spectrum computed by linearized buckling analysis in the context of topology optimization. Spurious buckling modes commonly appear in low density regions, but this study also highlights the occurrence of localized modes in solid areas due to the limitations of linearized buckling analysis. The proposed remedy involves using filtering and erosion operations on the stress field, helping to mitigate the occurrence of spurious modes and improve the optimization process towards high performance designs.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2023)
Article
Acoustics
Peter Risby Andersen, Vicente Cutanda Henriquez, Niels Aage
Summary: The increasing interest in miniaturizing acoustic devices has highlighted the importance of accurate and efficient models of acoustic viscous and thermal losses, especially in micro-acoustic devices. While using the full linearized Navier Stokes equations for modeling losses is computationally expensive, the use of an approximate boundary layer impedance boundary condition has become popular due to its high efficiency. However, applying the boundary layer impedance can be problematic when boundary layers overlap, impacting optimization results and design possibilities.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Computer Science, Interdisciplinary Applications
Lukas C. Hoghoj, Cian Conlan-Smith, Ole Sigmund, Casper Schousboe Andreasen
Summary: This paper presents a method for simultaneous optimization of the outer shape and internal topology of aircraft wings, with the objective of minimizing drag subject to lift and compliance constraints for multiple load cases. The physics are evaluated by the means of a source-doublet panel method for the aerodynamic response and linear elastic finite elements for the structural response, which are one-way coupled. Wings of small fixed-wing airplanes both with and without a stiffening strut are optimized. The resulting wings show internal topologies with struts and wall-truss combinations, depending on the design freedom of the shape optimization. The lift distributions of the optimized wings show patterns like the ones obtained when performing optimization of wing shapes with constraints on the bending moment at the root.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2023)
Article
Energy & Fuels
Vaishnavi Kale, Niels Aage, Marc Secanell
Summary: A variable density, stress-constrained topology optimization approach is used to optimize the rotor of a flywheel energy storage system (FESS). A new specific energy maximization optimization formulation is proposed to eliminate the need for an arbitrary volume fraction constraint. Factors such as operating speed, maximum stress, rotational symmetry, and rotor material are investigated to understand their effects on optimal topology and energy capacity.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Mathematics, Interdisciplinary Applications
Andreas Henrik Frederiksen, Ole Sigmund, Konstantinos Poulios
Summary: This paper addresses the limitations of incorporating contact in topology optimization and proposes a new method for topology optimization problems with internal contact. The method ensures stability and robustness of the optimized designs by introducing a tangent stiffness requirement and penalizing small features. The examples demonstrate the effectiveness of the method in topology optimization under large deformations.
COMPUTATIONAL MECHANICS
(2023)
Article
Engineering, Multidisciplinary
Weichen Li, Yingqi Jia, Fengwen Wang, Ole Sigmund, Xiaojia Shelly Zhang
Summary: This study systematically investigates several precisely programmed nonlinear extreme responses in 3D structures under finite deformations through multimaterial inverse design by topology optimization. Unique complex 3D geometries with deformation capabilities are discovered and utilized to deliver the target responses. The optimized structure is accurately fabricated through a proposed hybrid fabrication method and the design's programmed behavior is validated.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2023)
Article
Acoustics
Peter Risby Andersen, Gyeong-Tae Lee, Daniel Gert Nielsen, Junghwan Kook, Vicente Cutanda Henriquez, Niels Aage, Yong-Hwa Park
Summary: This work focuses on the shape optimization and experimental validation of an acoustic lens for compact loudspeakers, such as those used in speakerphones. The optimization uses a combined lumped parameter and boundary element method model with a free form deformation geometry parameterization. The optimized design is 3D printed and characterized experimentally to verify its frequency response. The results show good agreement between measurements and simulations, although some shortcomings of the model assumptions are revealed.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2023)
Article
Engineering, Multidisciplinary
Rebekka Woldseth, J. Andreas Baerentzen, Ole Sigmund
Summary: This paper presents an alternative approach to dehomogenisation of elastic Rank-N laminate structures based on the computer graphics discipline of phasor noise. The proposed methodology offers an improvement of existing methods, where high-quality single-scale designs can be obtained efficiently without the utilisation of any least-squares problem or pre-trained models. Numerical tests verifies the performance of the proposed methodology compared to state-of-the-art alternatives, and the dehomogenised designs achieve structural performance within a few percentages of the optimised homogenised solution.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2024)