Finite Elements in Analysis and Design最新文献_第2页

A simple hybrid linear and nonlinear interpolation finite element for the adaptive Cracking Elements Method 一种简单的线性和非线性混合插值有限元自适应开裂单元法

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104295

Xueya Wang , Yiming Zhang , Minjie Wen , Herbert A. Mang

The Cracking Elements Method (CEM) is a numerical tool for simulation of quasi-brittle fracture. It neither needs remeshing, nor nodal enrichment, or a complicated crack-tracking strategy. The cracking elements used in the CEM can be considered as a special type of Galerkin finite elements. A disadvantage of the CEM is that it uses nonlinear interpolation of the displacement field (e.g. Q8 and T6 elements for 2D problems), introducing more nodes and consequently requiring greater computing efforts than in case of elements based on linear interpolation of the displacement field. With the aim to solve this problem we propose a hybrid linear and nonlinear interpolation finite element for the adaptive CEM presented in this work. A simple strategy is proposed for treating elements with

p

edge nodes, where

p \in (0, n)

, with

n

as the edge number of the considered element. Only a few program codes are needed. Then, by just adding edge and center nodes to the elements experiencing cracking, while keeping linear interpolation of the displacement field for the elements outside the cracking domain, the number of total nodes is reduced to almost one half of the number in case of using the conventional CEM. Numerical investigations have shown that the new approach not only preserves all of the advantages of the CEM, but also results in a significantly enhanced computing efficiency.

裂纹元素法（CEM）是一种模拟准脆性断裂的数值工具。它既不需要重网格化，也不需要节点富集或复杂的裂纹跟踪策略。CEM 中使用的裂纹元素可视为一种特殊的 Galerkin 有限元素。CEM 的一个缺点是它使用位移场的非线性插值（如二维问题中的 Q8 和 T6 元素），与基于位移场线性插值的元素相比，引入了更多的节点，因此需要更大的计算能力。为了解决这个问题，我们提出了一种线性和非线性混合插值有限元，用于本研究中提出的自适应 CEM。我们提出了一种简单的策略来处理具有 p 个边缘节点的元素，其中 p∈0,n，n 为所考虑元素的边缘数。只需少量程序代码。然后，只需在发生开裂的元素上添加边缘节点和中心节点，同时保持开裂域外元素位移场的线性插值，总节点数就会减少到使用传统 CEM 时的近一半。数值研究表明，新方法不仅保留了 CEM 的所有优点，还显著提高了计算效率。

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引用次数: 0

Development of C1 smooth isogeometric functions for planar multi-patch domains for NURBS based analysis 基于NURBS分析的平面多贴片域光滑等几何函数的发展[公式省略]

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104300

Lokanath Barik, Abinash Kumar Swain

This paper proposes a novel framework for constructing

C^{1}

smooth isogeometric functions on the planar multipatch domain. We extend the concept of

C^{1}

coupling, wherein the null space approach was used to construct geometrically continuous basis functions as linear combinations of

C^{0}

basis functions near patch junctions. However, due to the lack of continuity constraints, the resulting approximate basis functions violated the partition of unity and non-negativity properties. The proposed framework enforces the partition of unity and non-negativity conditions through additional equations, preserving higher-order continuity across the interface. The patch coupling algorithm provided generates

C^{1}

smooth isogeometric functions for arbitrarily shaped planar multipatch geometries. The advantage of this proposed approach is a reduced degree of approximation and a smooth transition from 1D to 2D patch coupling methodology. The computational effort to determine a new set of basis functions is significantly reduced due to the partition of unity property. Numerical studies are performed for the Kirchhoff–Love plate and biharmonic equations on various curved multipatch geometries, including an additional patch test. Enhanced numerical accuracy is observed for geometries with curved interfaces and boundaries. The accuracy and numerical efficiency of the proposed framework are analysed through

L^{2}

and

H_{0}^{2}

errors, showing optimal convergence behaviour for different polynomial orders. Furthermore, well-conditioned global matrices are observed with increasing refinement levels, demonstrating the efficiency of the methodology.

提出了一种在平面多斑域上构造C1光滑等几何函数的新框架。我们扩展了C1耦合的概念，其中使用零空间方法将几何连续基函数构造为补丁结点附近C0基函数的线性组合。然而，由于缺乏连续性约束，得到的近似基函数违背了单位划分和非负性。该框架通过附加方程强制统一和非负性条件的分割，保持了界面上的高阶连续性。所提供的贴片耦合算法对任意形状的平面多贴片几何图形生成C1光滑等距函数。该方法的优点是降低了近似程度，并且从1D到2D的补丁耦合方法平滑过渡。由于单位性质的划分，大大减少了确定一组新基函数的计算量。数值研究进行了Kirchhoff-Love板和双调和方程在各种弯曲的多斑几何，包括一个额外的斑测试。对于具有弯曲界面和边界的几何图形，可以观察到更高的数值精度。通过L2误差和H02误差分析了该框架的精度和数值效率，在不同多项式阶下显示出最优收敛性。此外，观察到良好条件的全局矩阵随着改进水平的提高，证明了该方法的效率。

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引用次数: 0

An hp-finite element for vibration analysis of laminates reinforced with curvilinear fibres 曲线纤维增强层合板振动分析的hp有限元

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104280

Pedro Camacho, Pedro Ribeiro, Hamed Akhavan

In this paper, an approach to model thin composite plates reinforced with curvilinear fibres is presented and applied to analyse modes of vibration. Particular attention is given to plates with non-standard geometries, which are less commonly addressed in studies on this topic. Aiming to achieve accuracy with a small number of degrees-of-freedom, the model is based on Kirchhoff’s plate theory, combined with an hp-version finite element method. Assembling p-version Kirchhoff plate elements, while ensuring continuity, presents a significant challenge. Elastic connections are introduced to address this issue. Additionally, elastic boundaries are also considered to impose the boundary conditions. Regarding the reinforcing fibres, cubic polynomial splines are employed to represent the path of the fibres, which also adds to the proposed model generality. To discretise the displacement field of the plate, three sets of interpolation functions are investigated. The convergence properties of the model, and the effects of the intervening features, are analysed based on hp-refinement. The proposed approach is shown to require fewer degrees-of-freedom to effectively analyse irregular-shaped plates, when compared to the more commonly used h-version finite elements. Moreover, the capability of cubic polynomial splines to represent fibre paths is validated. The paper concludes with modal analysis of a composite plate with a complex shape to verify tailoring abilities of reinforcing curvilinear fibres.

本文提出了一种曲线纤维增强复合材料薄板的建模方法，并将其应用于振动模态分析。特别注意的是非标准几何形状的板，这是不太常见的研究在这个主题。该模型以Kirchhoff板理论为基础，结合hp版有限元法，以较少的自由度达到精度。装配p版Kirchhoff板元件，同时确保连续性，提出了重大挑战。为了解决这个问题，我们引入了弹性连接。此外，还考虑了弹性边界来施加边界条件。对于增强纤维，采用三次多项式样条来表示纤维的路径，这也增加了模型的通用性。为了离散板的位移场，研究了三组插值函数。在此基础上，分析了模型的收敛性和中间特征的影响。与更常用的h型有限元相比，所提出的方法需要更少的自由度来有效地分析不规则板。此外，验证了三次多项式样条曲线表示光纤路径的能力。最后对一种形状复杂的复合材料板进行了模态分析，验证了增强曲线纤维的裁剪能力。

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引用次数: 0

An innovative beam element with section components cohesive interaction for reinforced concrete frames 一种具有截面构件内聚相互作用的创新型梁单元，用于钢筋混凝土框架

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104307

S.Hamed Ebrahimi

The behavior of a Timoshenko concrete beam reinforced by ribbed steel rebars is a function of the cohesive interaction between the concrete and reinforcement provided via bond-slip or traction-separation law. Bond-slip interactions between top/bottom reinforcements and the concrete beam section considering the shear deformations have been studied in this paper in static loading and nonlinear material and geometry conditions.

In this regard, the hybrid beam element has been enriched with two additional interactive degrees of freedom which incorporate the constituted freedom of the top and bottom unions of compressive and tensile reinforcements.

For this purpose, a two-dimensional mesh of the section is added as considered in the multi-fiber and multiscale approaches to non-homogeneous materials simulation whereas, several benefits are provided among which are non-prismatic reinforced concrete beam analysis, arbitrary composite beam section architecture, processing damage, and tracking cracks through the beam section and accordingly through the length of the beam, Fiber Reinforced Polymer reinforcement and wrapping laminates analysis and design, considering prestressing beam sections and many other advantages.

钢筋加筋Timoshenko混凝土梁的性能是混凝土与钢筋之间通过粘结-滑移或牵引-分离规律提供的内聚相互作用的函数。本文研究了静荷载和非线性材料几何条件下考虑剪切变形的顶/底钢筋与混凝土梁截面之间的粘结滑移相互作用。

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引用次数: 0

Formulating finite elements representing a given microstructure without using homogenisation 在不使用均质化的情况下，制定代表给定微观结构的有限元

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104306

Kazem Ghabraie

A framework is proposed to directly calculate the stiffness matrix of a macro-element equivalent to a desired microstructure. In a sense, this approach enables the estimation of the “homogenised” properties of microstructures without using the homogenisation theory. The proposed framework is based on assumed displacement fields within equivalent macro-elements. Different displacement assumptions are briefly discussed and two equivalent macro-elements are formulated. Several numerical tests are performed and discussed to show the potentials and limitations of the equivalent macro-elements. The numerical results show that one of the formulated elements can provide reasonable accuracy improvements, particularly in stress calculations. A sensitivity analysis is provided allowing the proposed equivalent macro-elements to be used in topology optimisation. The numerical results show that the formulated elements can effectively enhance the resolution of the boundaries in optimised solutions to obtain smooth designs.

提出了一种框架，可以直接计算等效于期望微观结构的宏观单元的刚度矩阵。从某种意义上说，这种方法可以在不使用均质化理论的情况下估计微观结构的“均质化”特性。所提出的框架是基于等效宏单元内假定的位移场。简要讨论了不同的位移假设，并建立了两个等效的宏观单元。进行了几个数值试验，讨论了等效宏单元的潜力和局限性。数值计算结果表明，其中一种公式单元可以提供合理的精度提高，特别是在应力计算中。灵敏度分析允许在拓扑优化中使用所提出的等效宏元素。数值结果表明，所建立的单元可以有效地提高优化解的边界分辨率，从而获得光滑的设计。

引用次数: 0

An adaptive mesh refinement algorithm for stress-based phase field fracture models for heterogeneous media: Application using FEniCS to ice-rock cliff failures 非均质介质应力相场破裂模型的自适应网格细化算法：fenic在冰岩断崖破坏中的应用

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104311

Duc Tien Nguyen , Abhinav Gupta , Ravindra Duddu , Chandrasekhar Annavarapu

Fracture propagation in heterogeneous ice-rock cliffs and hanging glaciers is complicated by the presence of internal interfaces and material property mismatch, so their failure risk is difficult to assess. Despite recent advances, phase-field fracture modeling is computationally expensive for large-scale homogeneous and heterogeneous material media. Here, we present an adaptive mesh refinement algorithm for the stress-based phase-field fracture model for heterogeneous media, implemented within the open-source finite element software package FEniCS. The novelty of the proposed algorithm includes its ability to handle material heterogeneity by representing elastic and fracture properties as fields via material distribution functions. These properties, along with the solution fields, are then appropriately transferred during the mesh refinement process without requiring a redefinition. We present several numerical studies to benchmark the method and analyze fracture predictions in idealized homogeneous and heterogeneous rock and ice-rock domains. Through these studies, we demonstrate the method’s accuracy and efficiency of simulations in multi-dimensions, and examine the effect of material properties and the interface inclination on fracture propagation. The results indicate that the mismatch of material properties at the rock-rock and ice-rock interfaces and the critical stress for fracture initiation can have a significant influence on crack propagation, including depth, length, and orientation. In three-dimensional geological fracture simulations, non-adaptive meshes would require handling billions of elements, whereas the proposed algorithm reduces the final mesh size to fewer than a million, demonstrating substantial computational savings and making it a practical approach for geological fracture simulation.

非均质冰岩峭壁和悬空冰川的断裂扩展由于内部界面的存在和材料性质的不匹配而变得复杂，因此其破坏风险难以评估。尽管近年来取得了一些进展，但对于大规模的均质和非均质材料介质，相场裂缝建模的计算成本很高。在这里，我们提出了一种基于应力的异质介质相场裂缝模型的自适应网格细化算法，该算法在开源有限元软件包FEniCS中实现。该算法的新颖之处在于，它能够通过材料分布函数将弹性和断裂性能表示为场，从而处理材料的非均匀性。这些属性，以及解决方案字段，然后在网格细化过程中适当地转移，而不需要重新定义。我们提出了几个数值研究，以基准方法和分析裂缝预测在理想的均质和非均质岩石和冰岩域。通过这些研究，我们证明了该方法在多维模拟中的准确性和有效性，并研究了材料性能和界面倾角对断裂扩展的影响。结果表明，岩石-岩石和冰-岩石界面处材料特性的不匹配以及起裂临界应力对裂纹扩展（包括深度、长度和方向）有显著影响。在三维地质裂缝模拟中，非自适应网格将需要处理数十亿个元素，而该算法将最终网格尺寸减少到不到100万个，显示出大量的计算节省，使其成为地质裂缝模拟的实用方法。

{"title":"An adaptive mesh refinement algorithm for stress-based phase field fracture models for heterogeneous media: Application using FEniCS to ice-rock cliff failures","authors":"Duc Tien Nguyen , Abhinav Gupta , Ravindra Duddu , Chandrasekhar Annavarapu","doi":"10.1016/j.finel.2024.104311","DOIUrl":"10.1016/j.finel.2024.104311","url":null,"abstract":"<div><div>Fracture propagation in heterogeneous ice-rock cliffs and hanging glaciers is complicated by the presence of internal interfaces and material property mismatch, so their failure risk is difficult to assess. Despite recent advances, phase-field fracture modeling is computationally expensive for large-scale homogeneous and heterogeneous material media. Here, we present an adaptive mesh refinement algorithm for the stress-based phase-field fracture model for heterogeneous media, implemented within the open-source finite element software package FEniCS. The novelty of the proposed algorithm includes its ability to handle material heterogeneity by representing elastic and fracture properties as fields via material distribution functions. These properties, along with the solution fields, are then appropriately transferred during the mesh refinement process without requiring a redefinition. We present several numerical studies to benchmark the method and analyze fracture predictions in idealized homogeneous and heterogeneous rock and ice-rock domains. Through these studies, we demonstrate the method’s accuracy and efficiency of simulations in multi-dimensions, and examine the effect of material properties and the interface inclination on fracture propagation. The results indicate that the mismatch of material properties at the rock-rock and ice-rock interfaces and the critical stress for fracture initiation can have a significant influence on crack propagation, including depth, length, and orientation. In three-dimensional geological fracture simulations, non-adaptive meshes would require handling billions of elements, whereas the proposed algorithm reduces the final mesh size to fewer than a million, demonstrating substantial computational savings and making it a practical approach for geological fracture simulation.</div></div>","PeriodicalId":56133,"journal":{"name":"Finite Elements in Analysis and Design","volume":"244 ","pages":"Article 104311"},"PeriodicalIF":3.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142986238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adaptive Interface-PINNs (AdaI-PINNs) for transient diffusion: Applications to forward and inverse problems in heterogeneous media 瞬态扩散的自适应接口- pinn (adai - pinn)：在非均质介质中正反问题中的应用

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104305

Sumanta Roy , Dibakar Roy Sarkar , Chandrasekhar Annavarapu , Pratanu Roy , Brice Lecampion , Dakshina Murthy Valiveti

We model transient diffusion in heterogeneous materials using a novel physics-informed neural networks framework (PINNs) termed Adaptive interface physics-informed neural networks or AdaI-PINNs (Roy et al. arXiv preprint arXiv:2406.04626, 2024). AdaI-PINNs utilize different activation functions with trainable slopes tailored to each material region within the computational domain, allowing for a fully automated and adaptive PINNs approach to model interface problems with strongly and weakly discontinuous solutions. To enhance its performance in highly heterogeneous transient diffusion systems, we prescribe a suite of robust practices, including appropriate non-dimensionalization of equations, a biased sampling method, Glorot initialization, and the hard enforcement of boundary and initial conditions. We evaluate the efficacy of the proposed method on several benchmark forward and inverse problems. Comparative studies on one-dimensional and two-dimensional benchmark problems reveal that the modified AdaI-PINNs outperform its unmodified counterpart, achieving root-mean-square errors that are at least two orders of magnitude better in forward problems. For inverse problems, the maximum errors in the approximated diffusion coefficients by modified AdaI-PINNs are four orders of magnitude better than those of the unmodified version. Additionally, modified AdaI-PINNs demonstrate improved stability in problems with large material mismatches.

我们使用一种新型物理信息神经网络框架（PINNs）对异质材料中的瞬态扩散进行建模，该框架被称为自适应界面物理信息神经网络或 AdaI-PINNs（Roy 等人，arXiv 预印本 arXiv:2406.04626, 2024）。AdaI-PINNs 利用不同的激活函数，针对计算域中的每个材料区域定制可训练斜率，从而实现了全自动自适应 PINNs 方法，为具有强不连续和弱不连续解的界面问题建模。为了提高 PINNs 在高度异质瞬态扩散系统中的性能，我们规定了一系列稳健的做法，包括适当的非尺寸化方程、偏置采样方法、Glorot 初始化以及边界和初始条件的严格执行。我们在几个基准正演和反演问题上评估了所提方法的有效性。对一维和二维基准问题的比较研究表明，修改后的 AdaI-PINNs 优于未修改的对应方法，在正向问题中取得的均方根误差至少提高了两个数量级。在逆向问题中，修正的 AdaI-PINN 近似扩散系数的最大误差比未修正的版本好四个数量级。此外，修改后的 AdaI-PINNs 在材料失配较大的问题中表现出更高的稳定性。

{"title":"Adaptive Interface-PINNs (AdaI-PINNs) for transient diffusion: Applications to forward and inverse problems in heterogeneous media","authors":"Sumanta Roy , Dibakar Roy Sarkar , Chandrasekhar Annavarapu , Pratanu Roy , Brice Lecampion , Dakshina Murthy Valiveti","doi":"10.1016/j.finel.2024.104305","DOIUrl":"10.1016/j.finel.2024.104305","url":null,"abstract":"<div><div>We model transient diffusion in heterogeneous materials using a novel physics-informed neural networks framework (PINNs) termed Adaptive interface physics-informed neural networks or AdaI-PINNs (Roy et al. arXiv preprint arXiv:2406.04626, 2024). AdaI-PINNs utilize different activation functions with trainable slopes tailored to each material region within the computational domain, allowing for a fully automated and adaptive PINNs approach to model interface problems with strongly and weakly discontinuous solutions. To enhance its performance in highly heterogeneous transient diffusion systems, we prescribe a suite of robust practices, including appropriate non-dimensionalization of equations, a biased sampling method, Glorot initialization, and the hard enforcement of boundary and initial conditions. We evaluate the efficacy of the proposed method on several benchmark forward and inverse problems. Comparative studies on one-dimensional and two-dimensional benchmark problems reveal that the modified AdaI-PINNs outperform its unmodified counterpart, achieving root-mean-square errors that are at least two orders of magnitude better in forward problems. For inverse problems, the maximum errors in the approximated diffusion coefficients by modified AdaI-PINNs are four orders of magnitude better than those of the unmodified version. Additionally, modified AdaI-PINNs demonstrate improved stability in problems with large material mismatches.</div></div>","PeriodicalId":56133,"journal":{"name":"Finite Elements in Analysis and Design","volume":"244 ","pages":"Article 104305"},"PeriodicalIF":3.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142986240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Conditional value at risk for damage identification in structural digital twins

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2025.104316

Facundo N. Airaudo , Harbir Antil , Rainald Löhner

Given measurements from sensors and a set of standard forces, an optimization based approach to perform damage identification in structures is introduced. The key novelty lies in letting the loads and measurements to be random variables. Subsequently, the conditional-value-at-risk (CVaR) is minimized subject to the elasticity equations as constraints. CVaR is a risk measure that leads to minimization of rare and low probability events which the standard expectation cannot. The optimization variable is the (deterministic) strength factor which appears as a coefficient in the elasticity equation, thus making the problem nonconvex. Due to uncertainty, the problem is high dimensional and, due to CVaR, the problem is nonsmooth. An adjoint based approach is developed with quadrature in the random variables. This approach would enable the implementation of risk-averse digital twins. Numerical results are presented in the context of a plate, a large structure with trusses similar to those used in solar arrays or cranes, and a footbridge.

引用次数: 0

Finite element analysis-enabled optimization of process parameters in additive manufacturing 基于有限元分析的增材制造工艺参数优化

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104282

Jingyi Wang, Panayiotis Papadopoulos

A design optimization framework is proposed for process parameters in additive manufacturing. A finite element approximation of the coupled thermomechanical model is used to simulate the fused deposition of heated material and compute the objective function for each analysis. Both gradient-based and gradient-free optimization methods are developed. The gradient-based approach, which results in a balance law-constrained optimization problem, requires sensitivities computed from the fully discretized finite element model. These sensitivities are derived and subsequently applied to a projected gradient-descent algorithm. For the gradient-free approach, two distinct algorithms are proposed: a search algorithm based on local variations and a Bayesian optimization algorithm using a Gaussian process. Two design optimization examples are considered in order to illustrate the effectiveness of these approaches and explore the range of their usefulness.

针对增材制造中的工艺参数提出了一个设计优化框架。耦合热机械模型的有限元近似用于模拟加热材料的熔融沉积，并计算每次分析的目标函数。开发了基于梯度和无梯度的优化方法。基于梯度的方法会产生平衡定律约束的优化问题，需要从完全离散化的有限元模型中计算出敏感度。推导出这些敏感度后，将其应用于投影梯度-后裔算法。对于无梯度方法，提出了两种不同的算法：一种是基于局部变化的搜索算法，另一种是使用高斯过程的贝叶斯优化算法。为了说明这些方法的有效性并探索其实用范围，我们考虑了两个设计优化实例。

引用次数: 0

Designing novel vascular stents with enhanced mechanical behavior through topology optimization of existing devices 通过对现有设备的拓扑优化，设计具有增强机械性能的新型血管支架

IF 3.5 3区工程技术 Q1 MATHEMATICS, APPLIED

Finite Elements in Analysis and Design

Pub Date : 2025-02-01 DOI: 10.1016/j.finel.2024.104304

Nicola Ferro , Francesco Mezzadri , Dario Carbonaro , Emanuele Galligani , Diego Gallo , Umberto Morbiducci , Claudio Chiastra , Simona Perotto

A variety of different vascular stent designs are currently available on the market, featuring different geometries, manufacturing materials, and physical characteristics. Here, we propose a framework for designing innovative stents that replicate and enhance the mechanical properties of existing devices. The framework includes a Solid Isotropic Material with Penalization (SIMP)-based topology optimization formulation, assisted by the homogenization theory to constrain the mechanical response, along with a minimum length scale requirement to ensure manufacturability to the designed devices. The optimization problem, discretized on a sequence of computational meshes anisotropically adapted, generates a 2D stent unit cell, which can be automatically converted into a 3D digital version of the device. This virtual prototype is validated through in silico testing via a radial crimping simulation to assess the stent insertion into the catheter, prior to implantation. The results prove that the proposed framework can identify stent designs that are competitive with respect to existing devices in terms of relevant clinical requirements, such as foreshortening, radial stiffness and surface contact area.

目前市场上有多种不同的血管支架设计，其几何形状、制造材料和物理特性各不相同。在此，我们提出了一个设计创新支架的框架，以复制和增强现有设备的机械性能。该框架包括基于各向同性固体材料（Solid Isotropic Material with Penalization，SIMP）的拓扑优化表述，在均质化理论的辅助下约束机械响应，以及最小长度尺度要求，以确保所设计设备的可制造性。优化问题在一连串各向异性调整的计算网格上离散化，生成二维支架单元格，并可自动转换为设备的三维数字版本。该虚拟原型通过径向卷曲模拟进行硅测试验证，以评估支架植入导管前的插入情况。结果证明，在相关临床要求方面，如前缩短、径向刚度和表面接触面积，所提出的框架可以确定与现有装置相比具有竞争力的支架设计。

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引用次数: 0