• 제목/요약/키워드: predictor-corrector method

검색결과 84건 처리시간 0.027초

CONCERNING THE RADIUS OF CONVERGENCE OF NEWTON'S METHOD AND APPLICATIONS

  • Argyros, Ioannis K.
    • Journal of applied mathematics & informatics
    • /
    • 제6권3호
    • /
    • pp.685-696
    • /
    • 1999
  • We present local and semilocal convergence results for New-ton's method in a Banach space setting. In particular using Lipschitz-type assumptions on the second Frechet-derivative we find results con-cerning the radius of convergence of Newton's method. Such results are useful in the context of predictor-corrector continuation procedures. Finally we provide numerical examples to show that our results can ap-ply where earlier ones using Lipschitz assumption on the first Frechet-derivative fail.

The Efficient Algorithm for Simulating the Multiphase Flow

  • Yoon Seong Y;Yabe T.
    • 한국전산유체공학회지
    • /
    • 제9권1호
    • /
    • pp.18-24
    • /
    • 2004
  • The unified simulation for the multiphase flow by predictor-corrector scheme based on CIP method is introduced. In this algorithm, the interface between different phases is identified by a density function and tracked by solving an advection equation. Solid body motion is modeled by the translation and angular motion. The mathematical formulation and numerical results are also described. To verify the efficiency, accuracy and capability of proposed algorithm, two dimensional incompressible cavity flow, the motion of a floating ball into water and a single rising bubble by buoyancy force are numerically simulated by the present scheme. As results, it is confirmed that the present scheme gives an efficient, stable and reasonable solution in the multiphase flow problem.

비엇갈림 격자계에서 CIP법을 이용한 캐비티내의 유동해석 (Analysis of the Flow in Square Cavity Using CIP Method in Non-staggered Grid Arrangement)

  • 이정희;강준;임도균;김찬중
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2003년도 춘계학술대회
    • /
    • pp.1821-1826
    • /
    • 2003
  • In this study, we discuss CIP method, which can treat compressible/incompressible problem and multi-phase problem. We can apply this method to the general equations by using CCUP. In this paper, non-staggered grid arrangement and predictor-corrector method are used to enhance later development and the solution accuracy and convergence performance. To validate the numerical algorithm proposed in this paper, the two-dimensional unsteady flow in the driven cavity is simulated. The numerical results of this subject using the present algorithm are compared with other numerical results. As a result, it is prived that the present scheme gives stable and improved solutions, and the results even coarse grid are in good agreement with other result using a fine grid arrangement.

  • PDF

공작기계구조물의 다단계 최적화에 관한 연구 (A Study on Multiphase Optimization of Machine Tool Structures)

  • 이영우;성활경
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2002년도 추계학술대회 논문집
    • /
    • pp.42-45
    • /
    • 2002
  • In this paper, multiphase optimization of machine Tool structure is presented. The final goal is to obtain 1) light weight, 2) statically and dynamically rigid. and 3) thermally stable structure. The entire optimization process is carried out in three phases. In the first phase, multiple static optimization problem with two objective functions is treated using Pareto genetic algorithm. where two objective functions are weight of the structure and static compliance. In the second phase, maximum receptance is minimized using simple genetic algorithm. And the last phase, thermal deflection to moving heat sources is analyzed using Predictor-Corrector Method. The method is applied to a high speed line center design which takes the shape of back-column structure.

  • PDF

유한요소격자중첩을 이용한 복합재료평판의 변위 및 응력의 복원 (Local Response Recovery for Multilayered Composite Panels using Mesh Superposition)

  • 박진우;김용협
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2000년도 춘계학술발표대회 논문집
    • /
    • pp.89-92
    • /
    • 2000
  • In this paper, an effective procedure is presented for the local recovery of displacements and stresses in multilayered composite panels, which incorporate the local refinement using mesh superposition. The mesh superposition method is used to refine the global coarse mesh by superimposing refined mesh to the localized zone of interest without transition zones. The finite element model used is a solid element based on the Hellinger-Reissner variational principle. The a posteriori computation of the through-the-thickness distributions of displacements and stresses is achieved using a predictor-corrector procedure. The procedure utilizes the superconvergent stresses and nodal displacements of the finite element patch. The element patch is generated by locally superimposing a refined local mesh to the coarse global mesh.

  • PDF

동적해석을 위한 일반화된$\alpha$ 방범의 예측 수정자 알고리즘 (A predictor-corrector algorithm of the generalized-$\alpha$ method for analysis of structural dynamics)

  • 정진태
    • 소음진동
    • /
    • 제5권2호
    • /
    • pp.207-213
    • /
    • 1995
  • 본 논문에서 구조동력학 문제를 풀기 위한 명시적(explicit) 예측 수정자 시간적분법을 개발하였으며, 이 알고리즘은 최근 개발된 암시적(implicit) 일반화된 $\alpha$ 방법으로부터 유도하였다. 암시적 방법과 같이 명시적 일반화된 .alpha. 방법도 하나의 변수를 갖는 알고리즘의 집합이며, 이 변수는 고주파 영역에서 수치 감쇠의 양을 정의한다. 제안된 알고리즘은 수치감쇠가 없는 시간적분법으로 파의 젼달 문제를 풀때 나타나는 가상의 진동을 감소시키는 수치감쇠를 가지고 있기 때문 에 선형 혹은 비선형의 구조동력학 문제에 효과적으로 이용될 수 있다.

  • PDF

케이블-수중 예인체 시스템의 3차원 비선형 완전 연성해석 (3D Nonlinear Fully Coupled Simulation of Cable and Tow-fish System)

  • 고광수;이은택;안형택
    • 한국해양공학회지
    • /
    • 제30권6호
    • /
    • pp.458-467
    • /
    • 2016
  • In this paper, a strongly coupled method for investigating the interaction between a cable and tow-fish is presented. The nodal position finite element method was utilized to analyze the nonlinear cable dynamics, and 6DOF equations of motion were employed to describe the 3D rigid body motion of the tow-fish. Combining cable and tow-fish systems into a single formulation allowed the two nonlinear systems to be strongly coupled into a unified nonlinear system. This strongly coupled system was numerically integrated in the time domain using a predictor/multi-corrector Newmark algorithm. To demonstrate the validity, efficacy, and applicability of the current approach, two different scenarios (virtual and sea trial) were simulated, and the simulation results were validated using the physical plausibility and the sea trial test.

완전비선형 Boussinesq방정식을 이용한 쇄파대의 파랑변형 모의 (Surf Zone Wave Transformations Simulated by a Fully Nonlinear Boussinesq Equation)

  • 윤종태;김종무
    • 한국해안해양공학회지
    • /
    • 제13권4호
    • /
    • pp.296-308
    • /
    • 2001
  • Wei et al.의 완전비선형 Boussinesq방정식을 4차의 Adams predictorcorrector기법을 사용하여 차분하고 면 내부조파기법과 스폰지 경계충을 사용하였으며 쇄파구조를 추가하였다. 면 내부조파기법을 사용해 목적파를 잘 재현할 수 있었다. 비선형성이 부각되는 고립파의 천수실험을 통해 완전비선형 모형의 정화성을 확인할 수 있었고 해저평붕으로 인한 규칙파의 변형을 모의해 보았다. 쇄파 수치실험을 통해 적용된 쇄파구조의 특성을 확인해 보았고 수중천퇴에 대한 이차원 파랑전파 수치실험을 통해 비선형 모형의 중요성을 확인하였다.

  • PDF

강건 절점위치 유한요소법을 이용한 수중 예인 케이블의 비선형 거동해석 (Nonlinear Analysis of Underwater Towed Cable Using Robust Nodal Position Finite Element Method)

  • 이은택;고광수;안형택;김성일;천승용;김정석;이병희
    • 대한조선학회논문집
    • /
    • 제53권5호
    • /
    • pp.388-399
    • /
    • 2016
  • A motion analysis of an underwater towed cable is a complex task due to its nonlinear nature of the problem. The major source of the nonlinearity of the underwater cable analysis is that the motion of the cable involves large rigid-body motion. This large rigid-body motion makes difficult to use standard displacement-based finite element method. In this paper, the authors apply recently developed nodal position-based finite element method which can deal with the geometric nonlinearity due to the large rigid-body motion. In order to enhance the stability of the large-scale nonlinear cable motion simulation, an efficient time-integration scheme is proposed, namely predictor/multi-corrector Newmark scheme. Three different predictors are introduced, and the best predictor in terms of stability and robustness for impulsive cable motion analysis is proposed. As a result, the nonlinear motion of underwater cable is predicted in a very efficient manner compared to the classical finite element of finite difference methods. The efficacy of the method is demonstrated with several test cases, involving static and dynamic motion of a single cable element, and also under water towed cable composed of multiple cable elements.