• 제목/요약/키워드: finite element method.

검색결과 13,458건 처리시간 0.035초

Evaluation of Probabilistic Finite Element Method in Comparison with Monte Carlo Simulation

  • 이재영;고홍석
    • 한국농공학회지
    • /
    • 제32권E호
    • /
    • pp.59-66
    • /
    • 1990
  • Abstract The formulation of the probabilistic finite element method was briefly reviewed. The method was implemented into a computer program for frame analysis which has the same analogy as finite element analysis. Another program for Monte Carlo simulation of finite element analysis was written. Two sample structures were assumed and analized. The characteristics of the second moment statistics obtained by the probabilistic finite element method was examined through numerical studies. The applicability and limitation of the method were also evaluated in comparison with the data generated by Monte Carlo simulation.

  • PDF

유한요소-전달강성계수법에 의한 2차원 곡선 보 구조물의 정적해석 (Static Analysis of Two Dimensional Curbed Beam Structure by Finite Element-Transfer Stiffness Coefficent Method)

  • 최명수
    • 동력기계공학회지
    • /
    • 제21권6호
    • /
    • pp.40-45
    • /
    • 2017
  • The objective of this study is the finite element-transfer stiffness coefficient method, which is the combination of the modeling technique of finite element method and the transfer technique of transfer stiffness coefficient method, is applied in the static analyses of two dimensional curved beam structures. To confirm the effectiveness of the applied method, two computational models are selected and analyzed by using finite element method, finite element-transfer stiffness coefficient method and exact solution. The computational results of the static analyses for two computational models using finite element-transfer stiffness coefficient method are equal to those using finite element method. When the element partition number of curved beam structure is increased, the computational results of the static analyses using both methods approach the exact solution. We confirmed that the finite element-transfer stiffness coefficient method is superior to finite element method when the number of the curved beam elements is increased from the viewpoints of the computational speed and the utility of computer memory.

Finite volumes vs finite elements. There is a choice

  • Demirdzic, Ismet
    • Coupled systems mechanics
    • /
    • 제9권1호
    • /
    • pp.5-28
    • /
    • 2020
  • Despite a widely-held belief that the finite element method is the method for the solution of solid mechanics problems, which has for 30 years dissuaded solid mechanics scientists from paying any attention to the finite volume method, it is argued that finite volume methods can be a viable alternative. It is shown that it is simple to understand and implement, strongly conservative, memory efficient, and directly applicable to nonlinear problems. A number of examples are presented and, when available, comparison with finite element methods is made, showing that finite volume methods can be not only equal to, but outperform finite element methods for many applications.

MULTIGRID CONVERGENCE THEORY FOR FINITE ELEMENT/FINITE VOLUME METHOD FOR ELLIPTIC PROBLEMS:A SURVEY

  • Kwak, Do-Y.
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • 제12권2호
    • /
    • pp.69-79
    • /
    • 2008
  • Multigrid methods finite element/finite volume methods and their convergence properties are reviewed in a general setting. Some early theoretical results in simple finite element methods in variational setting method are given and extension to nonnested-noninherited forms are presented. Finally, the parallel theory for nonconforming element[13] and for cell centered finite difference methods [15, 23] are discussed.

  • PDF

유한요소의 개선에 따른 형상최적화 향상에 관한 연구 (A Study on the Improvement of Shape Optimization associated with the Modification of a Finite Element)

  • 성진일;유정훈
    • 대한기계학회논문집A
    • /
    • 제26권7호
    • /
    • pp.1408-1415
    • /
    • 2002
  • In this paper, we investigate the effect and the importance of the accuracy of finite element analysis in the shape optimization based on the finite element method and improve the existing finite element which has inaccuracy in some cases. And then, the shape optimization is performed by using the improved finite element. One of the main stream to improve finite element is the prevention of locking phenomenon. In case of bending dominant problems, finite element solutions cannot be reliable because of shear locking phenomenon. In the process of shape optimization, the mesh distortion is large due to the change of the structure outline. So, we have to raise the accuracy of finite element analysis for the large mesh distortion. We cannot guarantee the accurate result unless the finite element itself is accurate or the finite elements are remeshed. So, we approach to more accurate shape optimization to diminish these inaccuracies by improving the existing finite element. The shape optimization using the modified finite element is applied to a two and three dimensional simple beam. Results show that the modified finite element has improved the optimization results.

스펙트럴유한요소법을 이용한 네 변이 단순지지 된 직사각형평판의 진동해석 (Analysis of Simply Supported Rectangular Plate Using Spectral Finite Element Method)

  • 주경림;홍석윤;송지훈;김동진
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
    • /
    • pp.85-89
    • /
    • 2005
  • For the analysis of a vibrating two dimensional structure such as the simply supported rectangular plate, Spectral Finite Element Method (SFEM) has been studied. Under the condition that two parallel edges are simply supported at least and the other two edges can be arbitrary, Spectral Finite Element has been developed. Using this element SFEM is applied to the vibrating rectangular plate which all edges are simply supported, and obtain the frequency response function in frequency domain and the dynamic response in time domain. To evaluate these results normal mode method and finite element method (FEM) are also accomplished and compared. It is seen that SFEM is more powerful analysis tool than FEM in high frequency range.

  • PDF

환상압연 공정의 실용적 모델링 방법에 관한 연구 (A Study on the Practical Finite Element Modeling Method for Ring Rolling)

  • 이두규;김응주;이용신
    • 소성∙가공
    • /
    • 제24권3호
    • /
    • pp.161-166
    • /
    • 2015
  • The finite element method has been widely used in the analysis of ring rolling. For ring rolling it requires a high computational expense due to the non-steady state material flow characteristics of the process. The high computational expense causes the finite element analysis to be impractical for industrial applications. In the current study, we aim to develop a practical implicit finite element modeling method for ring rolling. This method uses a step-wise steady state assumption and is called the “Stepped method”. The stepped method divides the whole process time of unsteady-state flow model into a finite number of steady-state models. It then solves the process at several specific time steps until convergence is reached. In order to confirm the performance and validity of the newly proposed stepped method, the result from the stepped method were compared to the results from a Lagrangian finite element method and to results from experiments reported in the literature.

Formulation Method for Solid-to-Beam Transition Finite Elements

  • 임장권;송대한;송병호
    • Journal of Mechanical Science and Technology
    • /
    • 제15권11호
    • /
    • pp.1499-1506
    • /
    • 2001
  • Various transition elements are used in general for the effective finite element analysis of complicated mechanical structures. In this paper, a solid-to-beam transition finite element, which can b e used for connecting a C1-continuity beam element to a continuum solid element, is proposed. The shape functions of the transition finite element are derived to meet the compatibility condition, and a transition element equation is formulated by the conventional finite element procedure. In order to show the effectiveness and convergence characteristics of the proposed transition element, numerical tests are performed for various examples. As a result of this study, following conclusions are obtained. (1) The proposed transition element, which meets the compatibility of the primary variables, exhibits excellent accuracy. (2) In case of using the proposed transition element, the number of nodes in the finite element model may be considerably reduced and the model construction becomes more convenient. (3) This formulation method can be applied to the usage of higher order elements.

  • PDF

주파수응답함수를 이용한 유한요소모델의 개선 및 결합부 동정 (Updating of Finite Element Model and Joint Identification with Frequency Response Function)

  • 서상훈;지태한;박영필
    • 소음진동
    • /
    • 제7권1호
    • /
    • pp.61-69
    • /
    • 1997
  • Despite of the development in the finite element method, it is difficult to get the finite element model describing the dynamic characteristics of the complex structure exactly. Therefore a number of different methods have been developed in order to update the finite element model of a structure using vibration test data. This paper outlines the basic formulation for the frequency response function based updating method. One important advantage of this method is that the intermediate step of performing an eigensolution extraction is unnecessary. Using simulated experimental data, studies are conducted in the case of 10 DOF discrete system. The solution of noisy and incomplete experimental data is discussed. True measured frequency response function data are used for updating the finite element model of a beam and a plate. Its applicability to the joint identification is also considered.

  • PDF

A STRESS ANALYSIS FOR A COATED FUEL PARTICLE OF A HTGR USING A FINITE ELEMENT METHOD

  • Kim, Young-Min;Cho, Moon-Sung
    • Nuclear Engineering and Technology
    • /
    • 제41권8호
    • /
    • pp.1087-1100
    • /
    • 2009
  • A finite element method utilizing the Galerkin form of the weighted residuals procedure was developed to estimate the mechanical behavior for a coated fuel particle (CFP) of a high temperature gas-cooled reactor (HTGR). Through a weak formulation, finite element equations for multiple layers were set up to calculate the displacements and stresses in a CFP. The finite element method was applied to the stress analyses for three coating layers of a tri-isotropic coated fuel particle (TRISO) of a HTGR. The stresses calculated by the finite element method were in good agreement with those from a previously developed computer code and depicted the typical stress behavior of the coating layers very well. The newly developed finite element method performs a stress analysis for multiple bonded layers in a CFP by changing the material properties at any position in the layers during irradiation.