• 제목/요약/키워드: Mesh Generation

검색결과 525건 처리시간 0.027초

셀룰러 토폴로지를 이용한 솔리드 모델 스트리밍 (Streaming of Solid Models Using Cellular Topology)

  • 이재열;김현
    • 산업공학
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    • 제16권spc호
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    • pp.87-92
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    • 2003
  • Progressive mesh representation and generation have become one of the most important issues in network-based computer graphics. However, current researches are mostly focused on triangular mesh models. On the other hand, solid models are widely used in industry and are applied to advanced applications such as product design and virtual assembly. Moreover, as the demand to share and transmit these solid models over the network is emerging, the generation and the transmission of progressive solid models depending on specific engineering needs and purpose are essential. In this paper, we present a Cellular Topology-based approach to generating and transmitting progressive solid models from a feature-based solid model for internet-based design and collaboration. The proposed approach introduces a new scheme for storing and transmitting solid models over the network. The Cellular Topology (CT) approach makes it possible to effectively generate progressive solid models and to efficiently transmit the models over the network with compact model size.

셸 구조물의 중간면에 대한 삼각형 셸 요소망의 자동생성 (Automatic Generation of Triangular Shell Element Meshes on Mid-Surface in Shell Structure)

  • 문연철;양현익
    • 대한기계학회논문집A
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    • 제31권4호
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    • pp.451-460
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    • 2007
  • The surface of 3D shell structure is created by using NURBS and nodes for generating finite element mesh on the surface are created by using external node offset method. In so doing the shortest distance between nodes on the top and bottom surface is searched and then the coordinates of nodes are determined by calculating the mid point of them in the middle of top and bottom surface. Triangular elements are formed on mid surface, and the average aspect ratio of the generated triangular elements are over 0.9.

복잡한 지반 형상을 고려한 비선형 지반-구조물상호작용 해석 (Nonlinear Soil-Structure Interaction Analysis Considering Complicated Soil Profile)

  • 박장호
    • 한국안전학회지
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    • 제26권1호
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    • pp.36-42
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    • 2011
  • This paper presents a nonlinear soil-structure interaction analysis approach, which can consider precisely characteristics of structures, complicated soil profiles and nonlinear characteristics of soil. Although many methods have been developed to deal with the soil-structure interaction effects in past years, most of them are nearly unpractical since it is difficult to model complicated characteristics of structure and soil precisely. The presented approach overcomes the difficulties by adopting an maligned mesh generation approach and multi-linear model. The applicability of the proposed approach is validated and the effects of complicated characteristics of structure and soil on soil-structure interaction are investigated through the numerical example by the proposed nonlinear soil-structure interaction analysis approach.

삼차원 직교 격자 생성을 위한 단면 커브를 이용한 옥트리 생성과 셀 절단 알고리듬 (Octree Generation and Clipping Algorithm using Section Curves for Three Dimensional Cartesian Grid Generation)

  • 김동훈;신하용;박세연;이일랑;권장혁;권오준
    • 한국CDE학회논문집
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    • 제13권6호
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    • pp.450-458
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    • 2008
  • Recently, Cartesian grid approach has been popular to generate grid meshes for complex geometries in CFD (Computational Fluid Dynamics) because it is based on the non-body-fitted technique. This paper presents a method of an octree generation and boundary cell clipping using section curves for fast octree generation and elimination of redundant intersections between boundary cells and triangles from 3D triangular mesh. The proposed octree generation method uses 2D Scan-Converting line algorithm, and the clipping is done by parameterization of vertices from section curves. Experimental results provide octree generation time as well as Cut-cell clipping time of several models. The result shows that the proposed octree generation is fast and has linear relationship between grid generation time and the number of cut-cells.

THE EFFECTS OF MESH STYLE ON THE FINITE ELEMENT ANALYSIS FOR ARTIFICIAL HIP JOINTS

  • Shin, Jae-Min;Lee, Dong-Sun;Kim, Sung-Ki;Jeong, Da-Rae;Lee, Hyun-Geun;Kim, Jun-Seok
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제15권1호
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    • pp.57-65
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    • 2011
  • In this paper, a good quality mesh generation for the finite element method is investigated for artificial hip joint simulations. In general, bad meshes with a large aspect ratio or mixed elements can give rise to excessively long computational running times and extremely high errors. Typically, hexahedral elements outperform tetrahedral elements during three-dimensional contact analysis using the finite element method. Therefore, it is essential to mesh biologic structures with hexahedral elements. Four meshing schemes for the finite element analysis of an artificial hip joint are presented and compared: (1) tetrahedral elements, (2) wedge and hexahedral elements, (3) open cubic box hexahedral elements, and (4) proposed hexahedral elements. The proposed meshing scheme is to partition a part before seeding so that we have a high quality three-dimensional mesh which consists of only hexahedral elements. The von Mises stress distributions were obtained and analyzed. We also performed mesh refinement convergence tests for all four cases.

The Influence of Meshing Strategies on the Propeller Simulation by CFD

  • Bahatmaka, Aldias;Kim, Dong-Joon
    • Journal of Advanced Research in Ocean Engineering
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    • 제4권2호
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    • pp.78-85
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    • 2018
  • This paper presents a study of the effects of the free surface to marine propeller including the mesh effect of the models. In the present study, we conduct the numerical simulation for propeller performance employing the openwater test. The numerical simulations compare the meshing strategies for the propeller and show the effects on both thrust and torque. OpenFOAM is applied to solve the propeller problem and then open water performances of KCS propeller (KP505) are estimated using a Reynold-averaged Navier-Stokes equations (RANS) solver and the turbulence of the $K-{\omega}$ SST model. Unstructured meshes are used in the numerical simulation employing hexahedral meshing for mesh generation. The arbitrary mesh interfacing (AMI) and multiple rotating frame (MRF) are compared to define the best meshing strategy. The meshing strategies are evaluated through 3 classifications, i.e., coarse, medium, and fine mesh. Thus, the propeller can be performed utilizing the best mesh strategy. The computational results are validated by comparison with the experimental results. The $K_T$, $K_Q$, and efficiency of the propeller are compared to an experimental result and for all of the meshing strategies. Thus, the simulations show the influence of meshing in order to perform the propeller performances.

Mesh and turbulence model sensitivity analyses of computational fluid dynamic simulations of a 37M CANDU fuel bundle

  • Z. Lu;M.H.A. Piro;M.A. Christon
    • Nuclear Engineering and Technology
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    • 제54권11호
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    • pp.4296-4309
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    • 2022
  • Mesh and turbulence model sensitivity analyses have been performed on computational fluid dynamics simulations executed with Hydra and ANSYS Fluent for a single CANadian Deuterium Uranium (CANDU) 37M nuclear fuel bundle placed within a standard pressure tube. The goal of this work was to perform a methodical analysis to objectively determine an appropriate mesh and to gauge the sensitivity of different turbulence models for CANDU subchannel flow under isothermal conditions. The boundary conditions and material properties are representative of normal operating conditions in a high-powered channel of the Darlington Nuclear Generating Station. Four meshes were generated with ANSYS Workbench Meshing, ranging from 22 to 84 million cells, and analyzed here to determine an appropriate level of mesh resolution and quality. Five turbulence models were compared in the turbulence model sensitivity analysis: standard k - ε, RNG k - ε, realizable k - ε, SST k - ω, and the Reynolds Stress Model. The intent of this work was to gain confidence in mesh generation and turbulence model selection of a single bundle to inform the decision making of subsequent investigations of an entire fuel channel containing a string of twelve bundles.