• 제목/요약/키워드: Finite element method

검색결과 13,340건 처리시간 0.034초

The construction of second generation wavelet-based multivariable finite elements for multiscale analysis of beam problems

  • Wang, Youming;Wu, Qing;Wang, Wenqing
    • Structural Engineering and Mechanics
    • /
    • 제50권5호
    • /
    • pp.679-695
    • /
    • 2014
  • A design method of second generation wavelet (SGW)-based multivariable finite elements is proposed for static and vibration beam analysis. An important property of SGWs is that they can be custom designed by selecting appropriate lifting coefficients depending on the application. The SGW-based multivariable finite element equations of static and vibration analysis of beam problems with two and three kinds of variables are derived based on the generalized variational principles. Compared to classical finite element method (FEM), the second generation wavelet-based multivariable finite element method (SGW-MFEM) combines the advantages of high approximation performance of the SGW method and independent solution of field functions of the MFEM. A multiscale algorithm for SGW-MFEM is presented to solve structural engineering problems. Numerical examples demonstrate the proposed method is a flexible and accurate method in static and vibration beam analysis.

Quadratic B-spline finite element method for a rotating non-uniform Rayleigh beam

  • Panchore, Vijay;Ganguli, Ranjan
    • Structural Engineering and Mechanics
    • /
    • 제61권6호
    • /
    • pp.765-773
    • /
    • 2017
  • The quadratic B-spline finite element method yields mass and stiffness matrices which are half the size of matrices obtained by the conventional finite element method. We solve the free vibration problem of a rotating Rayleigh beam using the quadratic B-spline finite element method. Rayleigh beam theory includes the rotary inertia effects in addition to the Euler-Bernoulli theory assumptions and presents a good mathematical model for rotating beams. Galerkin's approach is used to obtain the weak form which yields a system of symmetric matrices. Results obtained for the natural frequencies at different rotating speeds show an accurate match with the published results. A comparison with Euler-Bernoulli beam is done to decipher the variations in higher modes of the Rayleigh beam due to the slenderness ratio. The results are obtained for different values of non-uniform parameter ($\bar{n}$).

유한요소법을 이용한 음향차폐장치용 탄성마운트 시스템 및 받침대의 진동모드 해석 (A Vibration Mode Analysis of Resilient Mounting System and Foundation Structure of Acoustic Enclosure using Finite Element Method)

  • 정우진;배수룡;함일배
    • 소음진동
    • /
    • 제9권3호
    • /
    • pp.493-501
    • /
    • 1999
  • The vibration modes of resilient mounting system and foundation structure which support diesel engine/generator set and acoustic enclosure walls play an important role in the vibration transmission process. So, it is necessary to perform vibration mode analysis of resilient mounting system and foundation structure. For some reasons, if the vibration modal analysis of resilient mounting system and foundation structure of acoustic enclosure could be simultaneously done by finite element method, it would be very efficient approach. In this paper, vibration modal analysis method using finite element method for multi stage mounting system having n d.o.f model was proposed. Vibration analysis of single and double stage resilient mounting system was performed to verify the validity of the proposed method. Also frequency response results were compared in case of rigid foundation model and finite element foundation model which was compared with experimental modal analysis results.

  • PDF

형상의 불확실성을 고려한 확률유한요소 해석 (Stochastic finite element analysis considering the uncertainty of shape)

  • 김영균;홍정표;김규탁;허진
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 하계학술대회 논문집 A
    • /
    • pp.200-202
    • /
    • 1999
  • A method of stochastic finite element analysis is developed for yield a uncertainty of engineering problems. Where, a stochastic finite-element method for shapes modeling is proposed a6 a means to solve the models with the uncertainty and variety. This method is based on the probability and illustrated by a first-Order Second-Moment Method and considering the covariance of random variables. The validity and accuracy of the stochastic finite element method is verified through comparing with those solved by the conventional 2-D finite element method.

  • PDF

시간차분 유한요소법을 이용한 대용량 삼상 변압기의 정상상태 해석에 관한 연구 (Study on Steady State Analysis of High Power Three-Phase Transformer using Time-Stepping Finite Element Method)

  • 윤희성;서민규;고창섭
    • 전기학회논문지
    • /
    • 제61권8호
    • /
    • pp.1123-1129
    • /
    • 2012
  • This paper presents the fast steady state analysis using time-stepping finite element method for a high power three-phase transformer. The high power transformer spends huge computational cost of the time-stepping finite element method. It is because that the high power transformer requires a lot of time to reach steady state by its large inductance component. In order to reduce computational cost, in this paper, the adaptive time-step control algorithm combined with the embedded 2nd 4th singly diagonally implicit Runge-Kutta method and the analysis strategy using variation of the winding resistance are studied, and their numerical results are compared with those from the typical time-stepping finite element method.

FINITE ELEMENT METHOD FOR SOLVING BOUNDARY CONTROL PROBLEM GOVERNED BY ELLIPTIC VARIATIONAL INEQUALITIES WITH AN INFINITE NUMBER OF VARIABLES

  • Ghada Ebrahim Mostafa
    • Nonlinear Functional Analysis and Applications
    • /
    • 제28권3호
    • /
    • pp.613-622
    • /
    • 2023
  • In this paper, finite element method is applied to solve boundary control problem governed by elliptic variational inequality with an infinite number of variables. First, we introduce some important features of the finite element method, boundary control problem governed by elliptic variational inequalities with an infinite number of variables in the case of the control and observation are on the boundary is introduced. We prove the existence of the solution by using the augmented Lagrangian multipliers method. A triangular type finite element method is used.

A spline finite element method on mapping

  • Ding, Hanshan;Shao, Rongguang;Ding, Dajun
    • Structural Engineering and Mechanics
    • /
    • 제4권4호
    • /
    • pp.415-424
    • /
    • 1996
  • This paper presents a newly suggested calculation method in which an arbitrary quadrilateral element with curved sides is transformed to a normal rectangular one by mapping of coordinates, then the two-dimensional spline is adopted to approach the displacement function of this element. Finally the solution can be obtained by the least-energy principle. Thereby, the application field of Spline Finite Element Method will be extended.

SUPERCONVERGENCE OF CRANK-NICOLSON MIXED FINITE ELEMENT SOLUTION OF PARABOLIC PROBLEMS

  • Kwon, Dae Sung;Park, Eun-Jae
    • Korean Journal of Mathematics
    • /
    • 제13권2호
    • /
    • pp.139-148
    • /
    • 2005
  • In this paper we extend the mixed finite element method and its $L_2$-error estimate for postprocessed solutions by using Crank-Nicolson time-discretization method. Global $O(h^2+({\Delta}t)^2)$-superconvergence for the lowest order Raviart-Thomas element ($Q_0-Q_{1,0}{\times}Q_{0,1}$) are obtained. Numerical examples are presented to confirm superconvergence phenomena.

  • PDF

A Study on Constructing the Inverse Element Generator over GF(3m)

  • Park, Chun-Myoung
    • Journal of information and communication convergence engineering
    • /
    • 제8권3호
    • /
    • pp.317-322
    • /
    • 2010
  • This paper presents an algorithm generating inverse element over finite fields GF($3^m$), and constructing method of inverse element generator based on inverse element generating algorithm. An inverse computing method of an element over GF($3^m$) which corresponds to a polynomial over GF($3^m$) with order less than equal to m-1. Here, the computation is based on multiplication, square and cube method derived from the mathematics properties over finite fields.