• Title/Summary/Keyword: 자동 요소망 생성

Search Result 68, Processing Time 0.045 seconds

유한요소망의 자동생성

  • 고현무
    • Journal of the KSME
    • /
    • v.27 no.6
    • /
    • pp.496-503
    • /
    • 1987
  • 지금까지 유한요소망의 자동생성 방법에 대하여 현재 보편적으로 쓰이고 있는 것을 중심으로 살펴보고자 한다. 특히 최근 유한요소해석을 포함한 설계의 완전자동화에 대한 연구 추세에 의해 형상 모델러의 기능이 중요하게 됨에 따라 유한요소망의 자동생성과 형상 모델러의 관계를 기술하였다. 유한요소망의 자동생성에 대한 현재 상황은, 3차원 고체의 경우 모든 가능한 상황에 대처할 수 있는 일반적인 자동생성방법을 위해서는 더 많은 진전이 이루어져야 할 것이다. 특히 이 경우, 2차원 문제와는 달리 해석전에 미리 사용자가 필요한 유한요소망의 밀도를 쉽게 예측할 수 없기 때문에 해석결과나 오류치 평가에 따라 유한요소망을 조절해가는 자체조절 기능이 더욱 중요하게 된다. 이 기능이 충분히 발달되면 자동생성의 문제점이나 그 원리의 복잡성등을 직접 해결할 필요성이 없어질 것이다.

  • PDF

An Efficient Triangular Mesh Generation Algorithm using Domain-wise Hash Structure (영역기반 해쉬구조를 이용한 효율적 삼각형 자동 요소망 생성 알고리듬 개발)

  • Kim, Tae-Joo;Cho, Jin-Yeon
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.32 no.9
    • /
    • pp.41-48
    • /
    • 2004
  • In this work, a domain-wise hash structure is developed for efficient data handling, and by using the developed domain-wise hash structure, an automatic triangular mesh generation algorithm is proposed. To generate the optimal nodal points and triangles efficiently, the advancing layer method and Delaunay triangulation method are utilized. To investigate the performance of the proposed algorithm, benchmarking tests are carried out for various models including convex, concave and complicated shapes through the developed object oriented C++ mesh generation code.

Automatic Hexahedral Mesh Generation using Face-offsetting Method (Face-offsetting 기법을 이용한 육면체 요소망 자동생성 기법)

  • Cho, Hyunjoo;Lee, Jeeho
    • Journal of the Korea Computer Graphics Society
    • /
    • v.22 no.2
    • /
    • pp.20-26
    • /
    • 2016
  • This paper proposes an automatic hexahedral mesh generation method, in which internal medial surfaces are established to partition a region using the face-offsetting method. In order to test the usability of the suggested method, aspect ratios and Jacobians of the generated mesh for two models are evaluated and compared with ones from existing methods. It is verified that the proposed medial surface generation and partitioning scheme based on the face-offsetting method can be effectively used in the automatic hexahedral mesh generation procedure.

An Algorithm of Automatic Mesh Generation by Recursive Subdivisions (순환적 분할에 의한 유한 요소망 자동 생성 알고리즘)

  • 이재영
    • Computational Structural Engineering
    • /
    • v.9 no.3
    • /
    • pp.145-155
    • /
    • 1996
  • This paper suggests a new algorithm of automatic mesh generation over planar domains with arbitrarily shaped boundaries and control curves. The algorithm is based on the method of recursively subdividing the domain by the path connecting, with minimum penalty value, two points on the super-loop, which consists of the boundaries and the control curves, The algorithm is not subject to any limitation on the shape of the domain, and its process can be fully automated. Therefore, this algorithm can be implemented into computer programs which require minimal user intervention while generating finite element meshes over complicated domains. This algorithm can also be easily extended for application to the generation of meshes over curved surfaces, or to the adaptive mesh generation.

  • PDF

Automatic FE Mesh Generation Technique using Computer Aided Geometric Design for Free-form Discrete Spatial Structure (CAGD를 이용한 프리폼 이산화 공간구조물의 유한요소망 자동생성기법)

  • Lee, Sang-Jin
    • Journal of Korean Association for Spatial Structures
    • /
    • v.10 no.2
    • /
    • pp.77-86
    • /
    • 2010
  • This paper provides background theories and numerical results of automatic finite element (FE) mesh generation for freeform discrete structures. The present method adopts the computer aided geometric design (CAGD) technique to overcome the limitation of case-sensitive traditional automatic FE mesh generator. The present technique involves two steps. The first one is to represent the shape of the structure using the geometric model based on the CAGD and the second one is to generate the discrete FE mesh of spatial structures over the geometric model. From numerical results, it is found to be that the present technique is very easy to produce the FE mesh for free-form spatial structures and it can also reuse some features of traditional automatic mesh generator in the process. Furthermore, it shows the possibility to be used for the shape optimization of large spatial structures.

  • PDF

Automatic Quadrilateral Element Mesh Generation Using Boundary Normal Offsetting In Various Two Dimensional Objects (다양한 2차원 형상에서의 외부 경계 절점 오프셋 방법을 이용한 자동 사각 요소 및 요소망 생성)

  • 김도헌;양현익
    • Korean Journal of Computational Design and Engineering
    • /
    • v.8 no.4
    • /
    • pp.270-277
    • /
    • 2003
  • In two dimensional mechanical design analysis, quadrilateral element mesh is preferred because it provides more accurate result than triangular element mesh. However, automation of quadrilateral element mesh generation is much more complex because of its geometrical complexities. In this study, an automatic quadrilateral element mesh generation algorithm based on the boundary normal offsetting method and the boundary decomposition method is developed. In so doing, nodes are automatically placed using the boundary normal offsetting method and the decomposition method is applied to decompose the designed domain into a set of convex subdomains. The generated elements are improved by relocation of the existing nodes based on the four criteria - uniformity, aspect ratio, skewness and taper degree. The developed algorithm requires minimal user inputs such as boundary data and the distance between nodes.

3D Tunnel Modeling by Parametric Representation of Geometry (매개변수식 기하 표현법에 의한 3차원 터널 모델링)

  • 이형우;신대석
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.15 no.1
    • /
    • pp.33-42
    • /
    • 2002
  • A method of automatic 3D tunnel modeling is proposed. The proposed method used the parametric representation of geometry and a hierarchical and relational data structure. These two bases provide the generalization and extension for 3D tunnel modeling. Especially, these two fundamentals ion the basis iota representing the characteristics of the tunnel structure for analysis. The constant-curvature characteristic is exploited to generate 3D mesh on the tunnel surface. This is attributed to the advantage that any 2D automatic mesh generation algorithm can be applied to 3D mesh modeling.

Composite Surface Modeling of Three-Dimensional Structures -Theory and Algorithms- (3차원(次元) 구조물(構造物)의 복합곡면(複合曲面)모델링-이론(理論) 및 알고리즘)

  • Koh, Hyun Moo;Park, Young Ha
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.10 no.4
    • /
    • pp.43-52
    • /
    • 1990
  • Theoretical foundation and algorithms are presented of a new surface modeling and pre-processing system for the three-dimensional structures. The modeling method is based on the boundary representation scheme and composed of two hierarchical model structures: curve-network and surface models. The concept of modeling curve as a union of links is introduced to facilitate surface modeling via various transfinite mapping techniques or Coons Patches. Efficiency and novel aspects of the present method are discussed. Finite element mesh genceration and application procedures will be reported in a later paper.

  • PDF

Automatic Generation of Finite Element Meshes on Midsurfaces in Shell Structures (셀 구조물에서 중립면에 대한 유한요소망의 자동생성)

  • Son Jun-Hee;Chae Soo-Won
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.28 no.10
    • /
    • pp.1517-1525
    • /
    • 2004
  • Shell finite elements are widely used for the analysis of thin section objects such as sheet metal parts, automobile bodies and et al. due to their computational efficiency. Since many of input data for finite element analysis are given as solid models or triangulated surface models, one should extract midsurface information from these input data initially and then construct shell meshes on the extracted midsurfaces. In this paper, a method of generating shell elements on midsurfaces directly from input models has been proposed, in which midsurface generating process can be omitted. In order to construct shell meshes, the input models should be triangulated on surfaces first, and then tetrahedral elements are generated by using an advancing front method, and finally mid shell surfaces are obtained from tetrahedral meshes. Some examples are given to demonstrate the efficiency of the proposed method.

Automatic Generation of Shell Elements by Using Chordal Axis Transform in 3D Structures (3 차원 구조물에서 Chordal Axis Transform 을 이용한 쉘 요소망의 자동생성)

  • Son, Jun-Hee;Chae, Soo-Won
    • Proceedings of the KSME Conference
    • /
    • 2004.04a
    • /
    • pp.700-705
    • /
    • 2004
  • Shell finite elements are widely used for the analysis of thin section objects such as sheet metal parts, automobile bodies and et al. due to their computational efficiency. Since many of input data for finite element analysis are given as solid models or triangulated surface models, one should extract midsurface information from these input data initially and then construct shell meshes on the extracted midsurfaces. In this paper, a method of generating shell elements on midsurfaces directly from input models have been proposed. In order to construct shell meshes, the input models should be triangulated on surfaces first, and then tetrahedral elements are generated by using an advancing front method, and finally mid shell surfaces are obtained from tetrahedral meshes. Some examples are given to demonstrate the efficiency of the proposed method.

  • PDF