Xun Liu, Li Chen^* , Wen-Quan Tao

Frontiers in Heat and Mass Transfer, Vol.14, No.1, pp. 1-9, 2020, DOI:10.5098/hmt.14.16

Abstract Fluid flow, mass transport and catalytic reaction in micro-reactors with catalyst are studied. Optimized structures of the catalyst generating the maximum reaction rate are explored by numerically solving the reactive transport processes combined with topology optimization schemes in COMSOL 5.3a. Effects of several physicochemical parameters including pressure drop, reaction rate constant, permeability of the porous catalyst and radius of the reactor are investigated. Distributions of the optimized structures, velocity, pressure and concentration are discussed in detail. Results show that the four physicochemical parameters have significant effects on the optimized structures of the catalyst obtained, indicating that generally there does not… More >

Yingjun Wang^1,*, Xinqing Li¹, Kai Long², Peng Wei³

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.1, pp. 1-34, 2023, DOI:10.32604/cmes.2023.027603

Abstract Topology optimization (TO), a numerical technique to find the optimal material layout with a given design domain, has attracted interest from researchers in the field of structural optimization in recent years. For beginners, opensource codes are undoubtedly the best alternative to learning TO, which can elaborate the implementation of a method in detail and easily engage more people to employ and extend the method. In this paper, we present a summary of various open-source codes and related literature on TO methods, including solid isotropic material with penalization (SIMP), evolutionary method, level set method (LSM), moving morphable components/voids (MMC/MMV) methods, multiscale… More > Graphic Abstract

Xuan Wang^1,2, Yuankun Shi², Van-Nam Hoang³, Zeng Meng^2,*, Kai Long^4,*, Yuesheng Wang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.3, pp. 3173-3195, 2023, DOI:10.32604/cmes.2023.025501

Abstract This paper proposes an effective reliability design optimization method for fail-safe topology optimization (FSTO) considering uncertainty based on the moving morphable bars method to establish the ideal balance between cost and robustness, reliability and structural safety. To this end, a performance measure approach (PMA)-based double-loop optimization algorithm is developed to minimize the relative volume percentage while achieving the reliability criterion. To ensure the compliance value of the worst failure case can better approximate the quantified design requirement, a p-norm constraint approach with correction parameter is introduced. Finally, the significance of accounting for uncertainty in the fail-safe design is illustrated by… More > Graphic Abstract

Rafael Marin Ferro^1,2,*, Renato Pavanello²

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1371-1397, 2023, DOI:10.32604/cmes.2023.026043

Abstract This work analyzes the implementation of a continuous method of structural topology optimization (STO) using open-source software for all stages of the topology optimization problem: modeling, sensitivity analysis and optimization. Its implementation involves three main components: numerical analysis using the Finite Element Method (FEM), sensitivity analysis using an Adjoint method and an optimization solver. In order to allow the automated numerical solution of Partial Differential Equations (PDEs) and perform a sensitivity analysis, FEniCS and Dolfin Adjoint software are used as tools, which are open-source code. For the optimization process, Ipopt (Interior Point OPTimizer) is used, which is a software package… More >

Jiazheng Du^*, Xue Cong, Ying Zhang

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1091-1120, 2023, DOI:10.32604/cmes.2023.025585

Abstract Spacecraft in the aerospace field and military equipment in the military field are at risk of being impacted by external objects, which can cause local damage to the structure. The randomness of local damage is a new challenge for structural design, and it is essential to take random damage into account in the conceptual design phase for the purpose of improving structure’s resistance to external shocks. In this article, a random damaged structure is assumed to have damages of the same size and shape at random locations, and the random damage is considered as multiple damage conditions of the structure.… More > Graphic Abstract

Chong Wang¹, Tongxing Zuo^1,2, Haitao Han^1,2, Qianglong Wang^1,2, Han Zhang¹, Zhenyu Liu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.1, pp. 655-683, 2023, DOI:10.32604/cmes.2023.025153

Abstract This paper presents an extended sequential element rejection and admission (SERA) topology optimization method with a region partitioning strategy. Based on the partitioning of a design domain into solid regions and weak regions, the proposed optimization method sequentially implements finite element analysis (FEA) in these regions. After standard FEA in the solid regions, the boundary displacement of the weak regions is constrained using the numerical solution of the solid regions as Dirichlet boundary conditions. This treatment can alleviate the negative effect of the material interpolation model of the topology optimization method in the weak regions, such as the condition number… More > Graphic Abstract

Peng Wei¹, Zirun Jiang¹, Weipeng Xu¹, Zhenyu Liu², Yongbo Deng^2,3, Minqiang Pan^4,*

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.1, pp. 593-619, 2023, DOI:10.32604/cmes.2023.023978

Abstract In this paper, we consider solving the topology optimization for steady-state incompressible Navier-Stokes problems via a new topology optimization method called parameterized level set method, which can maintain a relatively smooth level set function with a local optimality condition. The objective of topology optimization is to find an optimal configuration of the fluid and solid materials that minimizes power dissipation under a prescribed fluid volume fraction constraint. An artificial friction force is added to the Navier-Stokes equations to apply the no-slip boundary condition. Although a great deal of work has been carried out for topology optimization of fluid flow in… More >

Xiaoyan Teng¹, Qiang Li¹, Xudong Jiang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.3, pp. 2479-2496, 2023, DOI:10.32604/cmes.2023.023110

Abstract A smooth bidirectional evolutionary structural optimization (SBESO), as a bidirectional version of SESO is proposed to solve the topological optimization of vibrating continuum structures for natural frequencies and dynamic compliance under the transient load. A weighted function is introduced to regulate the mass and stiffness matrix of an element, which has the inefficient element gradually removed from the design domain as if it were undergoing damage. Aiming at maximizing the natural frequency of a structure, the frequency optimization formulation is proposed using the SBESO technique. The effects of various weight functions including constant, linear and sine functions on structural optimization… More >

Hongliang Liu¹, Peijin Wang¹, Yuan Liang^2,*, Kai Long³, Dixiong Yang²

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.3, pp. 1941-1964, 2023, DOI:10.32604/cmes.2023.024921

Abstract Continuum topology optimization considering the vibration response is of great value in the engineering structure design. The aim of this study is to address the topological design optimization of harmonic excitation structures with minimum length scale control to facilitate structural manufacturing. A structural topology design based on discrete variables is proposed to avoid localized vibration modes, gray regions and fuzzy boundaries in harmonic excitation topology optimization. The topological design model and sensitivity formulation are derived. The requirement of minimum size control is transformed into a geometric constraint using the discrete variables. Consequently, thin bars, small holes, and sharp corners, which… More >

Haoran Zhu, Xinhao Gao, Aodi Yang, Shuting Wang, Xianda Xie, Tifan Xiong^*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.2, pp. 1435-1456, 2023, DOI:10.32604/cmes.2022.023454

Abstract This work puts forward an explicit isogeometric topology optimization (ITO) method using moving morphable components (MMC), which takes the suitably graded truncated hierarchical B-Spline based isogeometric analysis as the solver of physical unknown (SGTHB-ITO-MMC). By applying properly basis graded constraints to the hierarchical mesh of truncated hierarchical B-splines (THB), the convergence and robustness of the SGTHB-ITOMMC are simultaneously improved and the tiny holes occurred in optimized structure are eliminated, due to the improved accuracy around the explicit structural boundaries. Moreover, an efficient computational method is developed for the topological description functions (TDF) of MMC under the admissible hierarchical mesh, which… More > Graphic Abstract