• 제목/요약/키워드: FEM(finite element analysis)

검색결과 2,826건 처리시간 0.033초

A Study on Moored Floating Body using Non-linear FEM Analysis

  • Ku, Namkug
    • Journal of Advanced Research in Ocean Engineering
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    • 제4권1호
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    • pp.25-34
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    • 2018
  • In this study, the behavior of the coupled mooring system and floating body is analyzed. The related works are introduced for the mooring analysis of the floating body. Equations motion are introduced for calculating mooring force connected with the floating body. For formulating the equations of motion, the concept of the constrained force is applied for compact expression of it. The input and output data of the module for calculating mooring force is defined. The static analysis and quasi-static analysis are performed. For the analysis, equilibrium equation for elastic catenary mooring line is used by employing finite element method, and the C# solver is developed in this research. The analysis results are validated by comparing with other research results.

경계 요소법에 의한 직교 이방성 다결정 재료의 응력해석에 관한 연구 (A Study of Stress Analysis of Multi-Grain Orthotropic Material by BEM)

  • 김동은;이상훈;정일중;이석순
    • 한국정밀공학회지
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    • 제25권4호
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    • pp.127-133
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    • 2008
  • As the application of the MEMS parts increases, the structural safety of MEMS appears importantly. A lot of MEMS parts are made by a multi-grain silicon wafer, which is an orthotropic material. Moreover directions of the materials on each grain are distributed randomly. The stress analysis for the multi-grain is important factor in order to apply the MEMS parts to industrial applications. The finite element method (FEM) is commonly used by a stress analysis method but the boundary element method (BEM) is known as the result of the BEM is more accurate than that of the FEM since the fundamental solution are used. In this study, we derived the boundary integration equation for the orthotropic material by applying fundamental solutions with complex variables. The multi-region analysis procedure for the BEM and the multi-grain generation procedure by a random process technique are developed in order to apply the analysis of the multi-grain orthotropic material. The discontinuous element is used in order to remove the comer problem in the BEM. The results of the present method are compared with those of the finite element method in order to verify the present procedure.

Multi-Domain Structural-Acoustic Coupling Analysis Using the Finite Element and Boundary Element Techniques

  • Ju, Hyeon-Don;Lee, Shi-Bok
    • Journal of Mechanical Science and Technology
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    • 제15권5호
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    • pp.555-561
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    • 2001
  • A new approach to analyze the multi-domain acoustic system divided and enclosed by flexible structures is presented in this paper. The boundary element formulation of the Helmholtz integral equation is used for the internal fields and the finite element formulation for the structures surrounding the fields. We developed a numerical analysis program for the structural-acoustic coupling problems of the multi-domain system, in which boundary conditions such as the continuity of normal particle velocity and sound pressure in the structural interfaces between Field 1 and Field 2 are not needed. The validity of the numerical analysis program is verified by comparing the numerical results with the experimental ones. Example problems are included to investigate the characteristics of the coupled multi-domain system.

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와전류탐상의 3차원 유한요소 정식화에 따른 특성 분석 (Characteristic Analysis of Eddy Current Testing According to the finite Element formulations)

  • 이향범
    • 비파괴검사학회지
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    • 제25권5호
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    • pp.384-390
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    • 2005
  • 3차원 유한요소법을 이용하여 와전류탐상의 수치해석을 수행하기 위하여 도체영역에서 자기벡터포텐셜과 전기스칼라포텐셜을 변수로 사용한다. 3차원 모델링을 하기 때문에 미지수가 많이 늘어나기도 하지만, 사용되는 변수 때문에 미지수가 급속히 증가한다. 이 때문에 전기스칼라포텐셜을 제거한 변형자기벡터포텐셜을 사용하여 미지수를 줄이기도 한다 또한 자기벡터포텐셜의 유일성을 보장하기 위하여 정식화 과정에 인위적으로 게이지조건을 집어넣기도 한다. 본 논문에서는 이러한 정식화 과정들이 와전류탐상에 미치는 영향을 검토하고, 와전류탐상에 적절한 정식화방법을 제시하였다.

복잡한 형상제품의 인크리멘탈 성형과 FEM을 이용한 공정 최적화 (Incremental Sheet Forming of Complex Geometry Shape and Its Optimization Using FEM Analysis)

  • 누엔 늑 뚜안;박진기;이혜진;김영석
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 춘계학술대회 논문집
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    • pp.207-212
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    • 2009
  • In order to optimize the press formability of incremental sheet forming for complex shape (e.g human face), a combination of both CAM and FEM simulation, is implemented and evaluated from the histories of stress and strain value by means of finite element analysis. Here, the results, using ABAQUS/Explicit finite element code, are compared with fracture limit curve (FLC) in order to predict and optimize the press formability by changing parameters of tool radius and tool down-step according to the orthogonal array of Taguchi's method. Firstly, The CAM simulation is used to create cutter location data (CL data). This data are then calculated, modified and exported to the input file format required by ABAQUS through using MATLAB programming. The FEM results are implemented for negative incremental sheet forming and then investigate by experiment.

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퍼지이론을 이용한 FEM 모델링을 위한 자동 요소분할 시스템 (Automatic Mesh Generation System for a Novel FEM Modeling Based on Fuzzy Theory)

  • 이양창;이준성;최윤종;김남용
    • 한국지능시스템학회논문지
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    • 제15권3호
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    • pp.343-348
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    • 2005
  • This paper describes an automatic finite element (FE) mesh generation for three-dimensional structures consisting of free-form surfaces. This mesh generation process consists of three subprocesses: (a) definition of geometric model, i.e. analysis model, (b) generation of nodes, and (c) generation of elements. One of commercial solid modelers is employed for three-dimensional solid structures. Node is generated if its distance from existing node points is similar to the node spacing function at the point. The node spacing function is well controlled by the fuzzy knowledge processing. The Delaunay method is introduced as a basic tool for element generation. Automatic generation of FE meshes for three-dimensional solid structures holds great benefits for analyses. Practical performances of the present system are demonstrated through several mesh generations for three-dimensional complex geometry.

FEM을 이용한 3-D 비선형 정자계 모델의 해석 (3-D Nonlinear Magnetostatic Analysis by using FEM)

  • 강병길;류재섭;고창섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 B
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    • pp.324-326
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    • 2000
  • A 3D magnetostatic field is analyzed considering the non-linear characteristics of the material using finite element method. In the finite element formulation, the edge element is adopted since it reduces the required computer memory and the computing time. The modified Newton-Raphson method is also used for non-linear analysis. A numerical example with the TEAM workshop problem 13 is analyzed, and the results are proved to concide well with measured ones.

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유한요소법에 의한 사면붕괴 거동해석에 미치는 영향분석 (Analysis for Effects of Slope Failure Behavior by Finite Element Method)

  • 김영민
    • 한국지반공학회논문집
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    • 제15권5호
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    • pp.19-28
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    • 1999
  • 본 논문에서는 사면붕괴해석에 대한 유한요소법의 적용에 대하여 검토하였다. 사면안정문제에 대해 가장 일반적으로 사용되는 방법은 한계평형이론에 의한 절편법이다. 또한 유한요소법은 지반의 응력, 변형률을 분석하는 방법으로 널리 인식되어 있다. 본 논문에서는 유한요소법으로 사면안정해석시, 요구되는 최소안전율 계산방법을 효율적으로 고려하는 방법에 대하여 검토하였다. 그리고 유한요소법으로 사면의 붕괴해석을 하는 경우에, 적용되는 해석방법 및 그 결과에 미치는 요인에 대하여 검토하였다. 또한, 여러 사면의 경우에 대하여 기존의 한계평형법에 의한 절편법과 유한요소 해석결과를 비교, 검토하였다.

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Tuning Fork Modal Analysis and Sound Pressure Calculation Using FEM and BEM

  • Jarng, Soon-Suck;Lee, Je-Hyung
    • The Journal of the Acoustical Society of Korea
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    • 제21권3E호
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    • pp.112-118
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    • 2002
  • An unconstrained tuning fork with a 3-D model has been numerically analyzed by Finite Element Method (FEM) and Boundary Element Method (BEM). The first three natural frequencies were calculated by the FEM modal analysis. Then the trend of the change of the modal frequencies was examined with the variation of the tuning fork length and width. An formula for the natural frequencies-tuning fork length relationship were derived from the numerical analysis results. Finally the BEM was used for the sound pressure field calculation from the structural displacement data.