Article
Computer Science, Interdisciplinary Applications
Van-Nam Hoang, Trung Pham, Duc Ho, H. Nguyen-Xuan
Summary: This paper presents a novel multiscale topology optimization approach that can optimize incompressible multi-material designs at both macro and micro scales, and demonstrates the effectiveness of the technique through examples of solving incompressible porous multi-material designs under single and multiple random loads.
ENGINEERING WITH COMPUTERS
(2022)
Article
Engineering, Mechanical
Jinhu Cai, Long Huang, Hongyu Wu, Lairong Yin
Summary: This study presents a robust concurrent topology optimization method for periodic microstructures considering dynamic load uncertainty. The objective function is formulated as a sum of the mean and standard deviation of the structural dynamic compliance modulus. Constraints are imposed on the macro-structure and material microstructure volumes. The proposed hybrid dimension reduction method and Gauss integral method quantifies and propagates load uncertainty for estimation of the objective function. A decoupled sensitivity analysis method is proposed to reduce computation burden.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Engineering, Multidisciplinary
Yifu Lu, Liyong Tong
Summary: This article introduces a mechanical cloaking technique that can hide objects and make them unfeelable. A generic method is developed to design cloaks for solids with a given stiffness by using metamaterials with spatially varying microstructures. A multiscale topology optimization model is proposed to investigate the concurrent optimization of structural topology and material properties of mechanical cloaking devices.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Computer Science, Interdisciplinary Applications
Bo Yang, Changzheng Cheng, Xuan Wang, Song Bai, Kai Long
Summary: This paper proposes a unified robust reliability-based topology optimization (RRBTO) approach for continuum structures considering loading uncertainty. An optimization model is established to minimize a linear combination of the mean and standard deviation of compliance response subject to a stress-based reliability constraint. To enhance computational efficiency, a polynomial chaos expansion-based surrogate modeling technique is adopted. 2D and 3D benchmark design examples are optimized and Monte Carlo simulation is implemented to verify the effectiveness of the proposed approach.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2023)
Article
Mechanics
Van-Nam Hoang, Xuan Wang, H. Nguyen-Xuan
Summary: This paper presents a direct multiscale design approach for 3D porous structures by using adaptive geometric components to describe the macrostructure and microstructure of materials, and utilizing multiresolution topology optimization to reduce the cost of finite element analysis. Optimization of geometry parameters simultaneously optimizes the overall macrostructure and microstructure of materials.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Multidisciplinary
Takayuki Nishino, Junji Kato
Summary: This study proposes a robust topology optimization method that considers uncertainties in load magnitude and direction on geometrically nonlinear structures. The method combines expected value and standard deviation of end-compliance, using quadratic approximation to reduce computational cost. The importance of considering geometrical nonlinearity for obtaining robust structures is emphasized through numerical examples.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2021)
Article
Engineering, Multidisciplinary
Mingdong Zhou, Yufan Lu, Yichang Liu, Zhongqin Lin
Summary: This paper presents a systematic design optimization approach for shells with self-supporting infills for Additive Manufacturing (AM). The design workflow involves concurrent Topology Optimization (TO) of the shells and infills, with a focus on overhang control and manufacturability requirements. By utilizing a density based TO approach and a two-field based formulation, the optimized infills can support the shells and meet mechanical properties regardless of voxel granularity.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Computer Science, Interdisciplinary Applications
Nolan Black, Ahmad R. Najafi
Summary: Concurrent multiscale structural optimization aims to improve macroscale structural performance by designing microscale architectures. This work uses deep learning models to increase microstructure complexity. The deep neural network is implemented as a model for both microscale structural properties and material shape derivatives. Compared to traditional methods, the deep neural network achieves sufficient accuracy and stability in structural optimization.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2023)
Article
Computer Science, Interdisciplinary Applications
Bin Niu, Eddie Wadbro
Summary: This paper introduces a novel design strategy to minimize the dynamic compliance of a vibrating infill structure with a solid outer coating and periodic uniform infill lattice. The study focuses on the effects of different conditions on the performance of the infill structure through multiscale topological designs and optimization methods.
COMPUTERS & STRUCTURES
(2021)
Article
Engineering, Manufacturing
Jaewook Lee, Chiyoung Kwon, Jeonghoon Yoo, Seungjae Min, Tsuyoshi Nomura, Ercan M. Dede
Summary: This paper introduces a systematic design procedure for shell-infill structures in additive manufacturing, utilizing multiscale topology optimization and a de-homogenization scheme compatible with Computer-Aided Design (CAD). The effectiveness of the design procedure is demonstrated through validation with design examples and fabrication using a multi-jet printing machine.
ADDITIVE MANUFACTURING
(2021)
Article
Thermodynamics
Musaddiq Al Ali, Masatoshi Shimoda
Summary: This paper investigates the application of multiscale topology optimization for lightweight and high heat conductive solid structures. A mathematical optimization model is introduced to concurrently optimize the macrostructure and micro-structure, and a sensitivity analysis is derived to address their coupling. The study compares three topology optimization methods and demonstrates the advantages of introducing various microstructures for weight reduction and performance improvement.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Mechanics
Xingjun Gao, Weihua Chen, Yingxiong Li, Gongfa Chen
Summary: This paper proposes an efficient method for robust multimaterial topology optimization problems of continuum structures under load uncertainty. The method minimizes the weighted sum of the mean and standard deviation of structural compliance for each material phase, separates the Monte Carlo sampling from the topology optimization procedure, and establishes an efficient procedure for sensitivity analysis. By using an alternating active-phase algorithm of the Gauss-Seidel version, the multi-material topology optimization problem is split into a series of binary topology optimization sub-problems, leading to the demonstration of the effectiveness of the proposed method through several 2D examples.
COMPOSITE STRUCTURES
(2021)
Article
Mathematics
Ang Zhao, Vincent Beng Chye Tan, Pei Li, Kui Liu, Zhendong Hu
Summary: This paper proposes a filtering-based reconstruction method to solve the checkerboard problem and provides an important solution for the practical application of multiscale topology optimization.
Article
Computer Science, Interdisciplinary Applications
Yanfang Zhao, Guikai Guo, Xinyu Xie, Wenjie Zuo
Summary: A concurrent topology optimization method is proposed for multiscale hollow design with lattice cells, considering geometrical nonlinearity. Lattice materials and hollow structures possess excellent mechanical properties, which are beneficial for lightweight product design.
ENGINEERING WITH COMPUTERS
(2023)
Article
Engineering, Multidisciplinary
Xiliang Liu, Liang Gao, Mi Xiao
Summary: This paper proposes a multiscale concurrent topology optimization method for design of hierarchal multi-morphology lattice structures. The method utilizes Kriging metamodel and sigmoid function based hybrid transition strategy to achieve smooth transition between multi-morphology lattice unit cells. It also employs KUMMI model to couple the design variables and optimize the relative densities of lattice unit cells. Numerical examples demonstrate the effectiveness and applicability of the proposed method, showing rational distribution of hierarchal multi-morphology lattice unit cells and superior structural performance.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Computer Science, Interdisciplinary Applications
Chien H. Thai, H. Nguyen-Xuan, P. Phung-Van
Summary: This paper presents a size-dependent high-order shear deformation theory (HSDT) model for analyzing the static and free vibration of laminated composite and sandwich nanoplates. By introducing scale parameters, the size effect of nanostructures is considered, and a virtual work principle is used to establish the bending and free vibration analysis model. The results show that the characteristics of the nanostructures are influenced by the geometry, boundary condition, length-to-thickness ratio, strain gradient parameter, and nonlocal parameter.
ENGINEERING WITH COMPUTERS
(2023)
Article
Computer Science, Interdisciplinary Applications
P. Phung-Van, H. Nguyen-Xuan, Chien H. Thai
Summary: This paper investigates the free vibration analysis of functionally graded graphene platelet-reinforced composites (FG GPLRC) plates using a nonlocal strain gradient isogeometric model based on the higher order shear deformation theory. Various distributed patterns of graphene platelets (GPLs) are considered, and the effects of different parameters on the natural frequencies of the nanoplates are examined. The results obtained in this study can serve as benchmark results for further research on FG GPLRC nanoplates.
ENGINEERING WITH COMPUTERS
(2023)
Article
Engineering, Marine
Bao-Loi Dang, Hung Nguyen-Xuan, Magd Abdel Wahab
Summary: In this paper, a systematic and time-efficient approach is proposed to calibrate 2D VARANS-VOF models for simulating wave interaction with a porous plate. A data-driven approach combined with numerical and experimental data is developed to identify the optimal empirical coefficients associated with drag force coefficients. Advanced gradient boosting decision trees algorithms are used to accurately predict the model parameters. The developed model is validated using available experimental data, showing a high level of agreement.
Article
Engineering, Civil
Van-Thien Tran, Trung-Kien Nguyen, H. Nguyen-Xuan, Magd Abdel Wahab
Summary: This paper proposes an algorithm for vibration and buckling optimization of functionally graded porous microplates and investigates the effects of material distribution, length scale, porosity density, and boundary conditions on their characteristics.
THIN-WALLED STRUCTURES
(2023)
Article
Engineering, Aerospace
Nam V. Nguyen, Kim Q. Tran, P. Phung-Van, Jaehong Lee, H. Nguyen-Xuan
Summary: In this study, an efficient numerical framework is proposed to explore the responses of functionally graded triply periodic minimal surface (FG-TPMS) microplates. The static bending, free vibration, and buckling characteristics of these structures are thoroughly presented for the first time. The study utilizes refined plate theory and isogeometric analysis to study these mechanical responses. It also takes into account the size effect with the modified couple stress theory. The findings contribute to the development and application of TPMS geometry in microscale structures.
AEROSPACE SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Multidisciplinary
Yun Lu Tee, H. Nguyen-Xuan, Phuong Tran
Summary: This paper investigates the bending behavior of porcupine quills and bioinspired Voronoi sandwich panels, aiming to understand the influence of geometrical design on their bending performance. X-ray micro-computed tomography is used to examine the internal morphology of the quill, revealing a functionally graded structure. Inspired by this, Voronoi sandwich panels are designed with Voronoi seed distribution and gradient transition configurations. Experimental results and simulations show that the graded panels exhibit better bending performance than the uniform panels. This study provides valuable insights for engineering applications in aerospace and automobile industries.
BIOINSPIRATION & BIOMIMETICS
(2023)
Article
Mechanics
Hien V. Do, Phuc L. H. Ho, Canh V. Le, H. Nguyen-Xuan
Summary: This study proposes a pseudo-lower bound method for direct limit analysis of two-dimensional structures and safety evaluation based on isogeometric analysis integrated through Bezier extraction. The key idea in this approach is that the stress field is separated into two parts: fictitious elastic and residual, and then the equilibrium conditions are recast using the weak form. The approximations based on the stress field automatically satisfy volumetric locking phenomena, unlike the displacement approach.
INTERNATIONAL JOURNAL OF APPLIED MECHANICS
(2023)
Article
Construction & Building Technology
Vuong Nguyen-Van, Chenxi Peng, Paul J. Hazell, Jaehong Lee, H. Nguyen-Xuan, Phuong Tran
Summary: Research on strengthening and retrofitting of concrete structures against explosive loading has gained significant attention recently. This study proposes a new reinforcement method using triply periodic minimal surface (TPMS)-primitive scaffold to enhance the blast-resistant capacity of concrete panels. A numerical model is developed to investigate the performance of TPMS-primitive reinforced concrete panels subjected to blast loading, and the results are validated using experimental data. The findings indicate that the TPMS-primitive scaffold improves damage resistance and reduces deflection of the concrete panels compared to traditional rebar lattice reinforcement.
STRUCTURAL CONCRETE
(2023)
Article
Engineering, Mechanical
Lieu B. Nguyen, H. Nguyen-Xuan, Chien H. Thai, P. Phung-Van
Summary: This paper presents a size-dependent isogeometric analysis approach for modeling smart functionally graded porous nanoscale plates made of two piezoelectric materials. The nonlocal elasticity theory is employed to consider size-dependent effects and the governing equations are obtained using a combination of higher-order shear deformation theory and non-uniform rational B-splines formulations. The paper investigates the influences of various factors on the natural frequencies of the smart nanoplate and compares the results with published documents, showing the reliability and effectiveness of the proposed method.
INTERNATIONAL JOURNAL OF MECHANICS AND MATERIALS IN DESIGN
(2023)
Article
Green & Sustainable Science & Technology
Thinh Huynh, Anh Tuan Pham, Jaehong Lee, H. Nguyen-Xuan
Summary: In this paper, a method for optimizing the component parameters of fuel cell hybrid electric vehicles (FCHEVs) is proposed to improve their performance and reduce operating costs. The balancing composite motion optimization (BCMO) algorithm is used to design the polymer electrolyte membrane fuel cell system, lithium-ion battery, electric motor, and differential unit. The proposed method takes into account the desired performance, hydrogen consumption, fuel cell system efficiency, and power source lifespan through a single cost function. Comparative studies validate the effectiveness of the method.
INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING-GREEN TECHNOLOGY
(2023)
Article
Mechanics
Chien H. Thai, A. M. J. Fereira, H. Nguyen-Xuan, P. Phung-Van, P. T. Hung
Summary: In this study, a nonlocal strain gradient isogeometric model for free vibration analysis of magneto-electro-elastic (MEE) nanoplates made of functionally graded (FG) materials is presented. The model takes into account higher-order shear deformation theory, nonlocal strain gradient theory, and isogeometric analysis method. The stiffness of MEE-FG nanoplates is shown to be influenced by two scale parameters. The natural frequency of the nanoplates is evaluated by considering the power-law scheme, geometrical parameter, nonlocal parameter, strain gradient parameter, electric voltage, and magnetic potential. The results obtained using nonlocal strain gradient theory (NSGT) are compared to those obtained using classical theory.
COMPOSITE STRUCTURES
(2023)
Article
Mechanics
H. Nguyen-Xuan, Kim Q. Tran, Chien H. Thai, Jaehong Lee
Summary: This paper investigates a new model of porous plates called Functionally Graded Triply Periodic Minimal Surface (FG-TPMS) plates. The effective moduli and Poisson's ratio of TPMS structures are evaluated using a fitting technique based on a two-phase piece-wise function. The mechanical characteristics of the FG-TPMS plates are verified through numerical examples, demonstrating their reliability and accuracy.
COMPOSITE STRUCTURES
(2023)
Article
Construction & Building Technology
Trung Kien Nguyen, Muhammad Shazwan Suhaizan, H. Nguyen-Xuan, Phuong Tran
Summary: This work proposes a new lightweight cellular concrete with controllable mechanical properties inspired by natural cellular structures, which is suitable for prefabricated engineering applications. 3D printed sacrificial formworks with lattice and TPMS architectures were used and infiltrated with foamed concrete of different densities. The compressive performance, air void characteristics, and failure mechanisms were investigated through numerical simulations and experimental tests. The gyroid cellular structure exhibited the highest compressive capacity and the bio-inspired architecture of the formworks significantly affected the air void distribution and compressive strength of the concrete.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Engineering, Civil
Chien H. Thai, P. T. Hung, H. Nguyen-Xuan, P. Phung-Van
Summary: In this paper, a new size-dependent meshfree method is introduced to analyze the free vibrations of magneto-electro-elastic (MEE) functionally graded (FG) nanoplates. The method combines the nonlocal strain gradient theory (NSGT), the higher-order shear deformation theory (HSDT), and meshfree method for the first time. The effective material properties of MEE-FG nanoplates are expressed using a power-law scheme. Numerical examples are given to investigate the effect of various parameters on the natural frequency of MEE-FG nanoplates.
ENGINEERING STRUCTURES
(2023)
Article
Engineering, Civil
Leonardo Leonetti, H. Nguyen-Xuan, Gui-Rong Liu
Summary: This paper investigates a new solid-shell finite element formulation, which introduces new stress variables and an extra smoothing region to improve the accuracy of the approximate solutions. The assumed natural strain and discrete shear gap techniques are employed to alleviate trapezoidal and shear locking. The proposed method successfully solves popular benchmark tests and avoids cross-diagonal meshes.
THIN-WALLED STRUCTURES
(2023)