A Hybrid Method for Finite Element Nodal Ordering

The objective of this study is to thoroughly investigate the dynamic characteristics of the Kao Ping Hsi Bridge located in southern Taiwan. A one-element cable system (OECS) and a multi-element cable system (MECS) are presented for simulating the dynamic properties of the cables of the bridge. By a finite element computation procedure, the initial shape, modal, and seismic analyses are conducted for the bridge using either the OECS or MECS model. A hybrid method combining both the two-loop iteration and the catenary function is proposed to determine the initial shapes using the MECS model. Convergent and smooth initial shapes can be obtained using such a method. The results indicate that the OECS model can yield solution in an efficient way, whereas the MECS model should be used if solutions of greater accuracy are desired.

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A hybrid solver based on the integral equation method and vector finite-element method for 3D controlled-source electromagnetic method modeling

Geophysics ◽

10.1190/geo2017-0502.1 ◽

2018 ◽

Vol 83 (5) ◽

pp. E319-E333 ◽

Cited By ~ 11

Author(s):

Rong Liu ◽

Rongwen Guo ◽

Jianxin Liu ◽

Changying Ma ◽

Zhenwei Guo

Keyword(s):

Differential Equation ◽

Finite Element Method ◽

Integral Equation ◽

Finite Element ◽

Differential Equations ◽

Electric Fields ◽

Hybrid Method ◽

Linear Equations ◽

Integral Equation Method ◽

Controlled Source

The integral equation method (IEM) and differential equation methods have been widely applied to provide numerical solutions of the electromagnetic (EM) fields caused by inhomogeneity for the controlled-source EM method. IEM has a bounded computational domain and has been well-known for its efficiency, whereas differential equation methods are commonly used for complex geologic models. To use the advantages of the two types of approaches, a hybrid method is developed based on the combination of IEM and the edge-based finite-element method (vector FEM). In the hybrid scheme, Maxwell’s differential equations of the secondary electric fields in the frequency domain are derived for a volume with boundary placed slightly away from the inhomogeneity. The vector FEM is applied to solve Maxwell’s differential equations, and a system of linear equations for the secondary electric fields can be derived by the minimum theorem. The secondary electric fields on the boundary are represented by IEM in terms of the secondary electric fields inside the inhomogeneity. The linear equations from substituting the boundary values into the vector FEM linear equations then can be solved to obtain the secondary electric fields inside the inhomogeneity. The secondary electric fields at receivers are calculated by IEM based on the secondary electric field solutions inside the inhomogeneity. The hybrid algorithm is verified by comparison of simulated results with earlier works on canonical 3D disc models with a high accuracy. Numerical comparisons with two conventional IEMs demonstrate that the hybrid method is more accurate and efficient for high-conductivity contrast media.

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Efficient analysis of welding thermal conduction using the Newton–Raphson method, implicit method, and their combination

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-020-06233-6 ◽

2020 ◽

Vol 111 (7-8) ◽

pp. 1929-1940 ◽

Cited By ~ 1

Author(s):

Zhongyuan Feng ◽

Ninshu Ma ◽

Wangnan Li ◽

Kunio Narasaki ◽

Fenggui Lu

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Hybrid Method ◽

Thermal Conduction ◽

Computing Time ◽

Implicit Method ◽

Heating Process ◽

Element Analysis ◽

Heating And Cooling ◽

Raphson Method

AbstractFinite element analysis is commonly used to investigate the thermal-mechanical phenomena during welding. To improve the computing efficiency of finite element analysis for welding thermal conduction, a novel Newton–Raphson method (NRM) without the computation of inverse matrix and a hybrid method combing the NRM and conventional implicit method (IMP) were developed. Comparison of computing time between the hybrid method implemented in an in-house software JWRIAN and the IMP used in a commercial software ABAQUS indicated that the computing speed of the former was about 4.5 times faster than that of the latter. Additionally, compared to the conventional IMP, the NRM exhibited higher computing efficiency in the analysis of transient thermal conduction during the welding heating process. Meanwhile, a combined hybrid method of the NRM and IMP was verified to be more efficient in analyzing the welding thermal conduction throughout the heating and cooling processes. Moreover, the thermal cycles computed by the hybrid method were consistent with those from experimental measurement, indicating the high accuracy of the hybrid method. Furthermore, the hybrid method was used to predict the temperature field of the corner boxing fillet joint welded by a low transformation temperature weld metal for generation of compressive residual stress.

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Optimization for an Electronic Card with a New Hybrid Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.682.143 ◽

2013 ◽

Vol 682 ◽

pp. 143-151 ◽

Cited By ~ 1

Author(s):

S. Assif ◽

H. Hachimi ◽

M. Agouzoul ◽

Rachid Ellaia ◽

A. El Hami ◽

...

Keyword(s):

Genetic Algorithm ◽

Finite Element ◽

Particle Swarm Optimization ◽

Mechanical Behavior ◽

Hybrid Method ◽

Optimal Structure ◽

Electronic Systems ◽

Swarm Optimization ◽

Robust Algorithm ◽

Performance Results

Embedded electronic systems are playing a very important role in several areas, such as in automotive, aerospace, telecommunications and medical sectors. To properly perform their functions, electronic systems must be reliable [2. So in this paper, we present a new hybrid method of optimization by the heuristics algorithms to evaluate the reliability of the electronic card by simulating its thermo-mechanical behavior. A model of simulation by finite element is developed to consider the maximal deformations due to the temperature; a mechanico-computing coupling is used to find the optimal structure. This powerful and robust algorithm which is based on hybridation of Genetic algorithm with Particle swarm optimization PSO gives performance results.

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Band-gap characteristics of elastic metamaterial plate with axial rod core by the finite element and spectral element hybrid method

Mechanics of Advanced Materials and Structures ◽

10.1080/15376494.2020.1863531 ◽

2021 ◽

pp. 1-18

Author(s):

Linzhongyang E ◽

Zhijing Wu ◽

Guangping Zou ◽

Fengming Li ◽

Chuanzeng Zhang ◽

...

Keyword(s):

Finite Element ◽

Band Gap ◽

Hybrid Method ◽

Spectral Element ◽

Gap Characteristics ◽

Elastic Metamaterial Plate

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An Efficient Parallel Hybrid Method of FEM-MLFMA for Electromagnetic Radiation and Scattering Analysis of Separated Objects

Applied Computational Electromagnetics Society ◽

10.47037/2020.aces.j.351004 ◽

2020 ◽

Vol 35 (10) ◽

pp. 1127-1136

Author(s):

Sheng Zuo ◽

Zhongchao Lin ◽

Zheng Yue ◽

Daniel Garcia Donoro ◽

Yu Zhang ◽

...

Keyword(s):

Finite Element ◽

Hybrid Method ◽

Information Exchange ◽

Domain Decomposition Method ◽

Near Field ◽

Computational Time ◽

Excellent Performance ◽

Parallel Hybrid ◽

Higher Order Method ◽

Complex Features

In order to meet the rapidly increasing demand for accurate and efficient analysis of complex radiating or scattering structures in the presence of electrically large objects, a finite element method (FEM)-multilevel fast multipole algorithm (MLFMA) hybrid method that based on the Finite Element-Iterative Integral Equation Evaluation (FE-IIEE) mesh truncation technique is proposed in this paper. The present method makes use of FEM for the regions with small and complex features and MLFMA for the analysis of the electrically large objects, which ensure the accuracy and applicability of the method are better than most commonly adopted FEM-high frequency technique (HFT) hybrid method. The mutual interactions between regions are taken into account in a fully coupled way through iterative near filed computation process. In order to achieve an excellent performance, both algorithms have been implemented together from scratch, being able to run over multi CPU cores. An efficient parallel FEM domain decomposition method (DDM) solver with exploiting geometrical repetitions is included to drastically reduce memory requirements and computational time in the calculation of large array antenna. Also, the parallel MLFMA is adopted to expedite the near-field information exchange between regions. Through numerical example, the effect of distance between regions on the convergence of the proposed hybrid method is studied, and it is shown that the proposed method converge well even if the distance is equal to 0.05λ. Through comparisons with an in-house higher order method of moments (HOMoM) code and commercial software FEKO, the accuracy and effectiveness of the implemented parallel hybrid method are validated showing excellent performance.

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