Engineering Analysis with Boundary Elements最新文献_第9页

A theoretical proof of superiority of Smoothed Finite Element Method over the conventional FEM 平滑有限元法优于传统有限元法的理论证明

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-11-02 DOI: 10.1016/j.enganabound.2024.106007

Yun Chen , Guirong Liu , Junzhi Cui , Qiaofu Zhang , Ziqiang Wang

{"title":"A theoretical proof of superiority of Smoothed Finite Element Method over the conventional FEM","authors":"Yun Chen , Guirong Liu , Junzhi Cui , Qiaofu Zhang , Ziqiang Wang","doi":"10.1016/j.enganabound.2024.106007","DOIUrl":"10.1016/j.enganabound.2024.106007","url":null,"abstract":"<div><div>Numerous simulations have shown that Smoothed Finite Element Method (S-FEM) performs better than the standard FEM. However, there is lack of rigorous mathematical proof on such a claim. This task is challenging since there are so many variants of S-FEM and the standard FEM theory in Sobolev space does not work for S-FEM because of the Smoothed Gradient. Another long-standing open problem is to establish the theory of <span><math><mi>α</mi></math></span>FEM parameter. The <span><math><mi>α</mi></math></span>FEM could be the most flexible and fastest S-FEM variant. Its energy is even exact if the parameter is fine-tuned. So this problem is practical and interesting. By the help of nonlinear essential boundary (geometry), Weyl inequalities (algebra) and matrix differentiation (analysis), this parameter problem leads us to estimate the eigenvalue-gap and energy-gap between S-FEM and FEM. Consequently, we provide a definite answer to the long-standing S-FEM superiority problem in a unified framework. The essential boundary, eigenvalue and energy are linked together by four new necessary and sufficient conditions which are simple, practical and beyond our expectations. The standard S-FEM source code can be reused so it is convenient to numerically implement. Finally, the cantilever and infinite plate with a circular hole are simulated to verify the proof.</div></div>","PeriodicalId":51039,"journal":{"name":"Engineering Analysis with Boundary Elements","volume":"169 ","pages":"Article 106007"},"PeriodicalIF":4.2,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Node's residual descent method for steady-state thermal and thermoelastic analysis 用于稳态热分析和热弹性分析的节点残差下降法

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-11-01 DOI: 10.1016/j.enganabound.2024.106018

Tailang Dong, Shanju Wang, Yuhong Cui

{"title":"Node's residual descent method for steady-state thermal and thermoelastic analysis","authors":"Tailang Dong, Shanju Wang, Yuhong Cui","doi":"10.1016/j.enganabound.2024.106018","DOIUrl":"10.1016/j.enganabound.2024.106018","url":null,"abstract":"<div><div>Thermoelastic problems are prevalent in various practical structures, wherein thermal stresses are of considerable concern for product design and analysis. Solving these thermal and thermoelastic problems for intricate geometries and boundary conditions often requires numerical computations. This study develops a node's residual descent method (NRDM) for solving steady-state thermal and thermoelastic problems. The method decouples the thermoelastic problem into a steady-state thermal problem and an elastic boundary value problem with temperature loading. Numerical validation indicates that the NRDM exhibits excellent performance in terms of precision, iterative convergence, and numerical convergence. The NRDM can readily couple steady-state thermal analysis with linear elastic analysis to enable thermoelastic analysis, which verifies its capability of solving multiphysics field problems. Moreover, the NRDM achieves second-order numerical accuracy using a first-order generalized finite difference algorithm, reducing the star's connectivity requirements while enhancing the convergence rate of the traditional generalized finite difference method (GFDM). Furthermore, the NRDM addresses the numerical challenges of material nonlinearity by simply updating the node thermal conductivities during iterations, without requiring frequent incremental linearization as in the GFDM, thus achieving improved computational efficiency.</div></div>","PeriodicalId":51039,"journal":{"name":"Engineering Analysis with Boundary Elements","volume":"169 ","pages":"Article 106018"},"PeriodicalIF":4.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Quadratic time elements for time-dependent fundamental solution in the BEM for heat transfer modeling 用于传热建模 BEM 中时间相关基本解的二次时间元素

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-11-01 DOI: 10.1016/j.enganabound.2024.106008

I.D. Horvat, J. Iljaž

{"title":"Quadratic time elements for time-dependent fundamental solution in the BEM for heat transfer modeling","authors":"I.D. Horvat, J. Iljaž","doi":"10.1016/j.enganabound.2024.106008","DOIUrl":"10.1016/j.enganabound.2024.106008","url":null,"abstract":"<div><div>In this paper, a quadratic time interpolation for temperature and a linear time interpolation for fluxes are implemented for the parabolic (time-dependent) fundamental solution-based scheme for solving transient heat transfer problems with sources using the subdomain BEM (boundary element method), which is the main innovation of this paper. The approach described in this work to incorporate the quadratic time variation does not require doubling the number of equations, which is otherwise required in the BEM literature, for the discretized problem to be well-conditioned. Moreover, the numerical accuracy, compared over an unprecedented range of the Fourier number (Fo) and source strength values, can help in selecting the appropriate scheme for a given application, depending on the rate of the heat transfer process and the included source term. The newly implemented scheme based on the parabolic fundamental solution is compared with the well-established elliptic (Laplace) scheme, where the time derivative of the temperature is approximated with the second-order finite difference scheme, on two examples.</div></div>","PeriodicalId":51039,"journal":{"name":"Engineering Analysis with Boundary Elements","volume":"169 ","pages":"Article 106008"},"PeriodicalIF":4.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Scaled boundary finite element method for an acoustic cavity with porous layer 带多孔层声腔的比例边界有限元法

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-11-01 DOI: 10.1016/j.enganabound.2024.106003

A.L.N. Pramod

引用次数: 0

Nonlinear generalized piezothermoelasticity of spherical vessels made of functionally graded piezoelectric materials 由功能分级压电材料制成的球形容器的非线性广义压热弹性

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-10-30 DOI: 10.1016/j.enganabound.2024.106010

S.M.H. Jani , Y. Kiani

{"title":"Nonlinear generalized piezothermoelasticity of spherical vessels made of functionally graded piezoelectric materials","authors":"S.M.H. Jani , Y. Kiani","doi":"10.1016/j.enganabound.2024.106010","DOIUrl":"10.1016/j.enganabound.2024.106010","url":null,"abstract":"<div><div>The present study investigates the thermoelastic response of a heterogeneous piezoelectric sphere under thermal shock loading. Boundary conditions as well as loading are considered as symmetric; thus, the response of the sphere is expected to be symmetric. All of the properties of the thick-walled sphere, including mechanical, electrical and thermal properties, are considered dependent on the radial position, except for the relaxation time, which is considered a constant value along the radius. The governing equations of the sphere have been derived under heterogeneous anisotropic assumptions. The general form of the second law of thermodynamics, which is nonlinear in nature, and is called nonlinear energy equation is used. The number of the established equations is three, which includes the motion equation, energy equation and Maxwell electrostatic equation of Maxwell. These equations are obtained in terms of radial displacement, temperature difference and electric potential. The energy equation is derived based on Lord and Shulman theory with a single relaxation time. In the next step, by introducing dimensionless variables, the governing equations are provided in dimensionless presentation. Then these equations have been discretized using generalized differential quadrature method. Also, in order to follow the solution of the equations in time domain, Newmark method has been used. Since the system of equations is nonlinear, Picard algorithm is applied as a predictor-corrector mechanism to solve the nonlinear system of equations. Then numerical results are presented to investigate the propagation of mechanical, thermal and electric waves inside the heterogeneous sphere and also their reflection from the outer surface of the sphere. By examining the results, it can be seen that mechanical and thermal waves propagate with a limited speed, while the speed of electric wave propagation is infinite.</div></div>","PeriodicalId":51039,"journal":{"name":"Engineering Analysis with Boundary Elements","volume":"169 ","pages":"Article 106010"},"PeriodicalIF":4.2,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142555010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Boundary element method for hypersingular integral equations: Implementation and applications in potential theory 超积分方程的边界元方法：势理论中的实施与应用

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-10-30 DOI: 10.1016/j.enganabound.2024.105999

E. Strelnikova , N. Choudhary , K. Degtyariov , D. Kriutchenko , I. Vierushkin

{"title":"Boundary element method for hypersingular integral equations: Implementation and applications in potential theory","authors":"E. Strelnikova , N. Choudhary , K. Degtyariov , D. Kriutchenko , I. Vierushkin","doi":"10.1016/j.enganabound.2024.105999","DOIUrl":"10.1016/j.enganabound.2024.105999","url":null,"abstract":"<div><div>The main objective of this paper is to develop effective numerical methods to solve hypersingular integral equations arising in various physical and mechanical applications. Both surface and contour integrals are considered. The novelty of the proposed approach lies in the exact formulas obtained for an arbitrary planar polygon in hypersingular integral estimations. A one-dimensional hypersingular integral equation is derived for axially symmetrical configurations, and analytical formulas are established for calculating the hypersingular parts. It is proved that the hypersingular component of the surface integral is equal to its hypersingular component along the tangent plane. These exact formulas enable the development of an effective numerical method based on boundary element implementation. Benchmark tests are considered, and the convergence of the proposed methods is demonstrated. Problems in crack analysis are formulated and solved using both surface and contour hypersingular integral equations. A comparison of the results is made between boundary element methods and finite element methods for penny-shaped cracks. Boundary value problems in fluid-structure interaction are considered, and numerical simulations are performed. An estimation of modes and frequencies of panel and blade vibrations when interacting with liquids is carried out.</div></div>","PeriodicalId":51039,"journal":{"name":"Engineering Analysis with Boundary Elements","volume":"169 ","pages":"Article 105999"},"PeriodicalIF":4.2,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142555011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

A hybrid PSO-WO algorithm for identification of irregular inner wall defects of a body in a thermal environment 用于识别热环境中不规则人体内壁缺陷的 PSO-WO 混合算法

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-10-30 DOI: 10.1016/j.enganabound.2024.106011

Wenchao Ji , Guojun Li , Chunguang Zhao , Zhi Yi , Linyang Wei , Shuangcheng Sun , Cunhai Wang

{"title":"A hybrid PSO-WO algorithm for identification of irregular inner wall defects of a body in a thermal environment","authors":"Wenchao Ji , Guojun Li , Chunguang Zhao , Zhi Yi , Linyang Wei , Shuangcheng Sun , Cunhai Wang","doi":"10.1016/j.enganabound.2024.106011","DOIUrl":"10.1016/j.enganabound.2024.106011","url":null,"abstract":"<div><div>Accurate knowledge of the inner wall defect shape of industrial thermal equipment (ITE) plays a crucial role in safety inspections. However, direct observation and measurement are challenging due to the high-temperature environment within ITE. To address this issue, the identification of irregular inner wall defect shape based inverse technology is studied in this work. A novel particle swarm optimization (PSO) coupled with the whale optimization (WO) algorithm (HPWA) is developed as solver for inverse problems to identify the inner wall defect irregular shape. This hybrid approach enhanced the late-stage convergence efficiency of WO while avoiding the local optima issue commonly faced by PSO. The radial integral boundary element method (RIBEM) is used for solving the transient heat transfer problem and obtain transient temperature data at measurement points for inverse problem simulations. It was chosen for its capability to effectively handle complex boundary shapes by discretizing only the domain boundaries. Additionally, the effect of the distance between outer and inner boundaries and measurement duration on the inverse results are thoroughly analyzed. Results show that the PSO-WO algorithm is robust to measurement errors and becomes more accurate with measurement points closer to the actual inner boundary position. Extending the measurement time has little effect on inversion results when the measurement period is long enough.</div></div>","PeriodicalId":51039,"journal":{"name":"Engineering Analysis with Boundary Elements","volume":"169 ","pages":"Article 106011"},"PeriodicalIF":4.2,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142555012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

A new method to solve the forward and inverse problems for the spatial Solow model by using Physics Informed Neural Networks (PINNs) 利用物理信息神经网络 (PINN) 解决空间索洛模型正演和反演问题的新方法

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-10-30 DOI: 10.1016/j.enganabound.2024.106013

Wanjuan Hu

引用次数: 0

An efficient scheme of calculating nearly singular integrals for the 3D BEM modeling of thin media 用于薄介质三维 BEM 建模的近奇异积分高效计算方案

IF 4.2 2区工程技术

Engineering Analysis with Boundary Elements Pub Date : 2024-10-30 DOI: 10.1016/j.enganabound.2024.106005

Y.C. Shiah , Jin-Jia Zhan , M.R. Hematiyan

引用次数: 0

Modeling variably saturated flows in porous media using the numerical manifold method 利用数值流形法模拟多孔介质中的可变饱和流动