Engineering Analysis with Boundary Elements最新文献_第4页

Linear energy-stable Runge–Kutta relaxation schemes for the Bi-flux diffusion model 双通量扩散模型的线性能量稳定龙格-库塔弛豫格式

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106087

Jiayue Xu , Cong Xie , Maosheng Jiang

This paper conducts an in-depth study of nonlinear Bi-flux diffusion models with one energy stable linear relaxation with regularized energy reformulation numerical scheme. This novel scheme combines the single diagonal implicit Runge–Kutta method (SDIRK) in temporal dimension and a meshless generalized finite difference method (GFDM) in spatial dimension. Thus in terms of spatial discretization high quality grids are not required and in terms of time discretization large time step is potential compared with the existing methods. The rigorous proof of the unconditional energy stable property for the scheme is presented. According to different values of the coefficient in nonlinear Bi-flux model, it could degenerate to Allen–Cahn equation, Fisher–Kolmogorov equation and extended Fisher–Kolmogorov model. The accuracy and the effectiveness of the proposed scheme are presented. Moreover, a large number of evolution processes for the nonlinear Bi-flux model under different regimes are demonstrated.

本文采用正则化的能量重构数值格式，对具有一能量稳定线性松弛的非线性双通量扩散模型进行了深入的研究。该方案结合了时间维的单对角隐式龙格-库塔法（SDIRK）和空间维的无网格广义有限差分法（GFDM）。因此，在空间离散化方面不需要高质量的网格，而在时间离散化方面，与现有方法相比，有可能实现更大的时间步长。给出了该方案无条件能量稳定性质的严格证明。根据非线性双通量模型中不同的系数值，它可以退化为Allen-Cahn方程、Fisher-Kolmogorov方程和扩展的Fisher-Kolmogorov模型。验证了该方案的准确性和有效性。此外，还证明了非线性双通量模型在不同状态下的大量演化过程。

引用次数: 0

A peridynamic method for creep and stress relaxation incorporating a novel fractional viscoelastic model 结合新型分数黏弹性模型的蠕变和应力松弛的周动力方法

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106104

Guosheng Wang , Wenwen He , Dechun Lu , Zhiqiang Song , Xiuli Du

A fractional viscoelastic kernel function is proposed to describe the modulus evolution during the creep and stress relaxation behavior of quasi-brittle materials. A unified fractional viscoelastic model for creep and stress relaxation is further developed, which has the advantages of few parameters and high accuracy. The model can be degenerated into the basic viscoelastic models under different values of fractional order. The relationship between the force state in non-ordinary state-based peridynamics and the stress tensor in the continuum mechanics constitutive model is established. The developed fractional viscoelastic model is then integrated into the peridynamic framework to create a unified creep and stress relaxation peridynamic method. The calibration method of the model parameters is also determined through the equivalence of the peridynamics and the continuum mechanics, and the influence rules of parameters on the viscoelastic behavior of materials are discussed. The effectiveness of the proposed peridynamic method is verified by numerical simulations of a plate, bar, slate, and beam. The proposed method can accurately describe the deformation process from continuous to discontinuous in creep and stress relaxation. This study provides a valuable numerical tool for simulating structural damage caused by creep and stress relaxation in engineering structures during long-term operation.

提出了一个分数黏弹性核函数来描述准脆性材料在蠕变和应力松弛过程中的模量演化。进一步建立了蠕变和应力松弛的统一分数黏弹性模型，该模型具有参数少、精度高的优点。该模型在不同分数阶值下可退化为基本粘弹性模型。建立了非一般状态周动力学中的力态与连续介质力学本构模型中的应力张量之间的关系。然后将所建立的分数阶粘弹性模型整合到周期动力学框架中，建立了统一的蠕变和应力松弛周期动力学方法。通过周动力学和连续介质力学的等效，确定了模型参数的标定方法，并讨论了参数对材料粘弹性行为的影响规律。通过对板、杆、板岩和梁的数值模拟，验证了该方法的有效性。该方法能准确描述蠕变和应力松弛过程中由连续到不连续的变形过程。该研究为模拟工程结构在长期运行过程中因蠕变和应力松弛引起的结构损伤提供了有价值的数值工具。

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引用次数: 0

Electromagnetic-thermal coupling simulation in high temperature superconducting bulk by peridynamic differential operator 高温超导体中电磁-热耦合的周动力微分算子模拟

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106097

Shouhong Shan , Huadong Yong , Youhe Zhou

The high temperature superconducting (HTS) bulk can operate in the liquid nitrogen temperature. A useful model describing superconductivity for engineering applications links electric field and current density, namely as E-J power law. Since the exponent of the E-J power law is usually set as 20∼50, the distribution of current density changes dramatically between the penetrated and unpenetrated regions, which brings a challenge to the numerical accuracy and convergence of the calculation. Furthermore, in order to simulate the heat transfer behavior between HTS bulk and its ambient environment during operation, the nonlinear flux boundary condition of temperature is employed. The peridynamic differential operator (PDDO) is a powerful tool to solve the mathematical model with PDEs. Utilizing the theory of the PDDO, the spatial partial derivative in the PDEs is converted into a corresponding non-local form. To verify our model, a comparison between the numerical results solved by the PDDO and finite element method is carried out. Finally, the effects of the global and local non-uniformity of critical current and thermal perturbation on the electromagnetic and thermal behaviors of the HTS bulk in the multi-pulsed field magnetization process are simulated.

高温超导体可以在液氮温度下工作。在工程应用中，描述超导性的一个有用模型将电场和电流密度联系起来，即E-J幂律。由于E-J幂律的指数通常设置为20 ~ 50，电流密度在穿透区和未穿透区之间的分布变化很大，这给计算的数值精度和收敛性带来了挑战。此外，为了模拟高温超导体在运行过程中与周围环境之间的换热行为，采用了温度的非线性通量边界条件。动力学微分算子（PDDO）是求解动力学微分算子数学模型的有力工具。利用偏微分方程理论，将偏微分方程中的空间偏导数转换为相应的非局部形式。为了验证模型的正确性，将PDDO法与有限元法求解的数值结果进行了比较。最后，模拟了临界电流的全局和局部不均匀性以及热扰动对高温超导体在多脉冲场磁化过程中的电磁和热行为的影响。

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引用次数: 0

Nonlocal modelling of temperature-dependent electrochemical corrosion using peridynamic operator method 基于周动力学算子的非局部温度依赖性电化学腐蚀建模

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106096

Dewei He , Zhiyuan Li , Dan Huang , Ding Chen , Xuehao Yao

A nonlocal nonlinear temperature-dependent electrochemical corrosion model is proposed in this paper. The corrosion process is described by the concentration of ions controlled by diffusion and electromigration, and the influence of temperature is taken into consideration as well. The weak form of governing equations is obtained by using the weighted residual method which is then reformulated in their nonlocal form by using the peridynamic operator method. Numerical examples of galvanic corrosion and pitting corrosion illustrate that the model is capable of determining the corrosion rate quantitatively and capturing the moving interface of corrosion naturally. The influence of temperature and inert inclusions on diffusivity and electrical conductivity are discussed as well, leveraging the advantages of peridynamics in directly solving discontinuous problems. The 2D and 3D simulation results both indicate that an elevated temperature accelerates corrosion, and the non-uniform temperature distributions lead to the formation of different pitting corrosion morphologies.

提出了一种非局部非线性温度依赖性电化学腐蚀模型。腐蚀过程由扩散和电迁移控制的离子浓度来描述，并考虑了温度的影响。首先利用加权残差法得到控制方程的弱形式，然后利用周动力算子法将控制方程的非局部形式重新表述。电偶腐蚀和点蚀的数值算例表明，该模型能够定量地确定腐蚀速率，并能自然地捕捉腐蚀的运动界面。讨论了温度和惰性夹杂物对扩散率和电导率的影响，利用周动力学在直接解决不连续问题中的优势。二维和三维模拟结果均表明，温度升高会加速腐蚀，温度分布的不均匀导致不同点蚀形态的形成。

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引用次数: 0

Dual distance transformations for evaluating domain integrals in the boundary integral equation of transient heat conduction 计算瞬态热传导边界积分方程域积分的对偶距离变换

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106103

Zhengxu Tan, Yunqiao Dong, Xingwang Bai

Accurate computation of domain integrals is indeed crucial for effective boundary element analysis of transient heat conduction problems. The progressive reduction of the time step can cause the time-dependent kernel within the integral to oscillate rapidly and exhibit near-singularity. Additionally, integration over the sub-triangular element with a large angle and large side length ratio will result in the circumferential near-singularity. The traditional distance transformation technique, while effective, is limited to the nearly singular integrals and addresses the near-singularity in only one direction. To enhance the accuracy of the domain integral computations, a dual distance transformations method is introduced. The (α, β) coordinate transformation is initially employed to separate the near-singularity. An appropriate distance transformation is then proposed to eliminate the near-singularity associated with the variable α. Furthermore, the circumferential near-singularity induced by the sub-triangle with poor shape is analyzed. Considering the integral form related to the variable β, another new distance transformation is finally established to mitigate the effect of the element shape. With the presented dual distance transformations method, the domain integrals can be accurately computed for different time steps and source point locations. The accuracy and efficiency of the proposed method are effectively proven through several numerical examples.

区域积分的精确计算对于瞬态热传导问题的有效边界元分析至关重要。时间步长的逐步减小会导致积分内的时变核快速振荡并呈现近奇异性。此外，在大角度、大边长比的次三角形单元上的积分会导致周向近奇点。传统的距离变换技术虽然有效，但仅限于近奇异积分，并且只能处理一个方向上的近奇异积分。为了提高域积分计算的精度，引入了对偶距离变换方法。首先采用（α, β）坐标变换分离近奇点。然后提出了一种适当的距离变换来消除与变量α相关的近奇异性。进一步分析了形状较差的子三角形引起的周向近奇点。考虑到与变量β相关的积分形式，最后建立了另一种新的距离变换，以减轻单元形状的影响。采用对偶距离变换方法，可以精确地计算出不同时间步长和不同源点位置的域积分。通过数值算例，有效地证明了该方法的准确性和有效性。

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引用次数: 0

Properties optimisation of nanostructures via machine learning: Progress and perspective 基于机器学习的纳米结构性能优化：进展与展望

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106063

Nurul Akmal Che Lah

Nanostructures play a vast role in the current Internet of NanoThings (IoNT) era due to remarkable properties and features that precisely impart their desired application functions in catalysis, energy and other fields. The exploration in understanding their minute features caused by the flexibility of compositional and complex atomic arrangement from the synthesis reaction widely opens for the in-depth discovery of their search space such as particle size, morphology and structures that controlled the characteristics. A wide range of possible compositions and various lattice atomic arrangements combined with small particle size distribution and large surface area create grand challenges to copy/differentiate their corresponding specific properties. Thus, the employment of machine learning (ML)-based strategies using the closed-loop experimental data from the nanostructure synthesis to help navigate and optimise for the large classes of data attributes related to the size, morphology and other properties from the trained model are reviewed. The data attributes are assisted by discussions of the selected case studies from the recent literature that highlight different condition nanostructures. The review concludes with a discussion of perspectives on the major challenges in the implementation of ML data-driven design in the field of nanostructure synthesis.

纳米结构在当前的纳米物联网（IoNT）时代发挥着巨大的作用，由于其显著的性质和特征，精确地赋予其在催化，能源和其他领域所需的应用功能。从合成反应中对其组成的灵活性和复杂的原子排列所引起的微小特征的探索，为深入发现其粒径、形态和结构等控制特征的搜索空间打开了广阔的大门。广泛的可能组成和各种晶格原子排列，结合小颗粒尺寸分布和大表面积，给复制/区分其相应的特定性质带来了巨大的挑战。因此，本文回顾了使用来自纳米结构合成的闭环实验数据的基于机器学习（ML）的策略，以帮助导航和优化与训练模型的大小、形态和其他属性相关的大类数据属性。数据属性是由最近的文献，突出不同条件的纳米结构选定的案例研究的讨论协助。本文最后讨论了在纳米结构合成领域实现机器学习数据驱动设计的主要挑战。

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引用次数: 0

A novel RBF-DDM method for modelling transient droplet spreading in simple oil shear flow 用于模拟简单油液剪切流中瞬态液滴扩散的新型 RBF-DDM 方法

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106099

Muhamad Dwi Septiyanto, Eko Prasetya Budiana, Syamsul Hadi

This current numerical model of droplet spreading in a simple oil shear flow is assessed using a hybrid combination of the radial basis function (RBF) and domain decomposition method (DDM). The complex interfacial interaction understanding of oil-water is challenging to consider appropriately with the RBF-DDM numerical solution. The governing equations, which consist of the Navier-Stokes equation in primitive variable form, the Cahn-Hilliard equation, and the Poisson equation, are solved using the Radial Basis Function (RBF) method for spatial derivatives and the forward Euler method for time derivatives. This combination of RBF and DDM successfully addressed the complex domain multifluid interaction, with the dense matrix solved in several subdomains. The capillary number (Ca) and initial oil velocity are two independent variables analyzed, with the deformation coefficient serving as the primary dependent variable. The findings reveal that both variables affect the deformation coefficient presented with the deformation based on non-dimensionalization time. As theoretically stated, the interfacial tension is inversely proportional to the Ca, meaning that a possibly high Ca leads to a higher deformation coefficient. To get accurate elaboration, the convergence analysis and statistical model analysis use root mean square divergence (RMSDIV) and root mean square error (RMSE), respectively.

采用径向基函数（RBF）和区域分解法（DDM）的混合组合方法对简单油剪切流中液滴扩散的现有数值模型进行了评估。RBF-DDM数值解对油水复杂界面相互作用的理解具有挑战性。控制方程由原始变量形式的Navier-Stokes方程、Cahn-Hilliard方程和Poisson方程组成，空间导数采用径向基函数（RBF）法，时间导数采用正演欧拉法求解。这种RBF和DDM的结合成功地解决了复杂域多流体相互作用问题，并在多个子域中求解了密集矩阵。毛细管数（Ca）和初始油速为两个自变量，变形系数为主要因变量。结果表明，这两个变量都会影响基于非量纲化时间的变形所呈现的变形系数。从理论上讲，界面张力与Ca成反比，这意味着可能较高的Ca会导致较高的变形系数。为了得到准确的阐述，收敛分析和统计模型分析分别使用均方根散度（RMSDIV）和均方根误差（RMSE）。

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引用次数: 0

A preconditioned 3D multi-domain FMIBEM for near-fault ground motion simulation considering the complete physical process of fault-path-layered sedimentary basin 考虑断径-层状沉积盆地完整物理过程的近断层地震动模拟预处理三维多域FMIBEM

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106088

Zhongxian Liu , Zhenen Huang , Qinghua Han , Lei Huang

Efficient and precise numerical methods, grounded in physical processes, are crucial for studying ground motion distribution in near-fault complex sites. This study introduces a preconditioned 3D multi-domain fast multipole indirect boundary element method (FMIBEM) that considers complete physical processes, including fault rupture, path propagation, and near-surface complex site response. The computational efficiency of the preconditioned FMIBEM in solving high-frequency ground motions (>3 Hz) is enhanced by over 97 % compared to the regular FMIBEM. Employing preconditioned FMIBEM, we simulate broadband (0–5 Hz) ground motions in near-fault sedimentary basins on a regular workstation, revealing that: (I) sedimentary basins, especially layered ones, significantly amplify near-fault ground motion, with the amplification coefficient of PGA exceeding 5.0; (II) layered sedimentary basins notably increase permanent displacement due to fault slip; (III) sedimentary basins transform unidirectional velocity pulses from fault slip into bidirectional pulses with larger amplitude and longer period.

基于物理过程的高效、精确的数值方法是研究近断层复杂地点地震动分布的关键。本文提出了一种预条件三维多域快速多极间接边界元方法（FMIBEM），该方法考虑了完整的物理过程，包括断层破裂、路径传播和近地表复杂场地响应。与常规FMIBEM相比，预处理FMIBEM在求解高频地面运动（> 3hz）时的计算效率提高了97%以上。利用预处理FMIBEM在常规工作站模拟近断层沉积盆地宽带（0 ~ 5 Hz）地震动，结果表明：(1)沉积盆地尤其是层状沉积盆地对近断层地震动有明显的放大作用，其PGA放大系数超过5.0；(2)层状沉积盆地因断层滑动导致永久位移显著增加；(3)沉积盆地将断层滑动的单向速度脉冲转化为振幅更大、周期更长的双向速度脉冲。

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引用次数: 0

Third-order MFS for solving two-dimensional Stokes flow problems 求解二维Stokes流动问题的三阶MFS

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106092

Chein-Shan Liu , Chia-Ming Fan , Chung-Lun Kuo

When the two-dimensional (2D) Stokes equations are formulated as two-coupled third-order partial differential equations, we prove two types particular solutions and develop the corresponding meshless third-order method of fundamental solutions (MFS) to solve the Stokes flow problems. The second MFS with more comprehensive bases is more accurate than the first MFS. Some examples are examined to exhibit the performance of the proposed two novel third-order methods of fundamental solutions.

将二维Stokes方程化为两耦合三阶偏微分方程，证明了两类特解，并建立了相应的无网格三阶基本解方法。基于更全面基础的第二次MFS比第一次MFS更准确。通过一些例子来证明所提出的两种新的三阶基本解方法的性能。

引用次数: 0

Efficient surface reconstruction for SPH method and its application to simulation of solid-solid contact and fluid-rigid body interaction SPH方法的高效表面重构及其在固-固接触和流-刚体相互作用模拟中的应用

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-02-01 DOI: 10.1016/j.enganabound.2024.106086

Yihua Xiao , Duping Zhai , Dongdong Jiang , Jianli Shao

Explicit surface reconstruction is useful for treating challenging boundary-related problems in smoothed particle hydrodynamics (SPH), for example, high-accuracy contact treatment. In this work, an efficient local surface reconstruction method (LSRM) is proposed. It first identifies boundary layer particles and then employs the Delaunay triangulation technique to reconstruct explicit surfaces from the boundary layer particles. The surface reconstruction efficiency of the LSRM is examined by two-dimensional and three-dimensional test cases and compared with that of a global surface reconstruction method (GSRM) proposed previously. Compared with the GSRM, the LSRM shows an increasing advantage in efficiency as the number of particles increases, and its efficiency can be dozens of times higher when the number of particles is large. The LSRM is incorporated into SPH for contact treatment and is used to simulate some typical contact problems. The simulation results show that the LSRM is applicable to solid-solid contact problems involving friction and large deformation and fluid-rigid body interaction problems with complex free surface phenomena. Compared with the GSRM, the LSRM can produce simulation results with similar accuracy and significantly improve the overall efficiency of SPH simulation.

显式表面重构有助于处理平滑粒子流体力学（SPH）中具有挑战性的边界相关问题，例如高精度接触处理。本研究提出了一种高效的局部表面重构方法（LSRM）。它首先识别边界层粒子，然后采用 Delaunay 三角测量技术从边界层粒子重建显式表面。通过二维和三维测试案例检验了 LSRM 的表面重建效率，并与之前提出的全局表面重建方法（GSRM）进行了比较。与 GSRM 相比，LSRM 的效率随着粒子数量的增加而不断提高，当粒子数量较多时，其效率可提高数十倍。将 LSRM 纳入 SPH 进行接触处理，并用于模拟一些典型的接触问题。模拟结果表明，LSRM 适用于涉及摩擦和大变形的固-固接触问题，以及具有复杂自由表面现象的流-刚体相互作用问题。与 GSRM 相比，LSRM 可以得到精度相近的模拟结果，并显著提高 SPH 模拟的整体效率。

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引用次数: 0