共查询到17条相似文献,搜索用时 174 毫秒
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六面体网格具有计算精度高、网格数量少等特点 ,是工程三维有限元分析一种重要网格。本文提出了一种基于栅格的六面体网格自动划分方法 ,它首先采用栅格法生成核心网格 ,然后把核心网格与模型边界拟合 ,为克服由于边界拟合造成的表面网格质量下降 ,采用包络表面网格的方法生成零厚度表层网格 ,通过表面网格平滑和内部节点位置平滑处理 ,最终生成具有较高质量的全六面体网格。网格划分实例说明 :该法具有原理简单 ,算法可靠 ,编程方便 ,划分网格质量高等特点。最后还对该算法进行了讨论。 相似文献
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铸造CAE技术是预测铸造缺陷、改进铸造工艺的有效方法,但其应用推广仍受到有限元网格划分技术的制约,许多复杂铸造工艺因为无法顺利地生成出合格的有限元网格而不能进行铸造CAE计算分析。本文提出了一种适用于任意复杂铸造工艺的有限元网格生成方法,并详述其中用到的关键技术和方法,包括隐式曲面几何描述方法、有限元网格尺寸智能化计算方法,以及有限元网格自动生成和网格质量优化方法。基于此算法,开发了有限元四面体网格划分前处理模块,能够为复杂铸造工艺的几何模型一键生成合格有限元网格,为铸造CAE技术的进一步推广和应用提供重要的技术保障。 相似文献
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本文提出了一种任意多边形域的四边形有限元网格全自动生成方法,该方法可以生成全部四边形,网格质量较好,速度也比较快。文中介绍了它的基本思想和算法实现,并给出了实例。该方法已用于汽车覆盖件零件等复杂几何开头的有限元网格划分。 相似文献
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提出了一种采用通用环形刀具对离散三角网格模型进行三坐标加工的等高线轨迹生成算法,算法包括三角网格模型的等距离偏置和水平面内的二维轨迹等距偏置.设计了基于面片的模型等距偏置方法,分析了凸边和凸点的特点并提出了保护轨迹的直线拟合生成算法.实例程序的运行证明,该算法稳定可靠、能快速有效地生成环形刀具的等高线轨迹. 相似文献
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《组合机床与自动化加工技术》2016,(5)
传统的零件公差规范设计一般只考虑功能要求和加工工艺,忽略实际工况的影响。针对以上不足,提出了一种基于实际工况的零件公差规范设计方法。首先依据小位移旋量(SDT)理论,建立零件公差数学模型;然后根据蒙特卡罗法求得实际要素的极限位置,生成模拟点并拟合得到规范表面模型,再转化为实体模型;最后通过有限元仿真,获得实际工况下的实体模型,对其进行规范操作,确定几何要素的最大偏差。通过实例分析,验证了该方法的可行性。 相似文献
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特别适用于金属成形模拟的四边形网格划分方法 总被引:3,自引:2,他引:3
本文提出了一种自动的四边形有限元网格生成法 ,其实质是把被划分区域无限地分割 ,直到整个区域全部由四边形单元组成。文中详细阐述了边界偏移、最优分割线确定和简易环的划分等关键技术。几个网格划分实例表明 ,该网格生成法能有效地把被划分域离散为高质量的网格 相似文献
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为了探索单元类型以及网格划分方式对航空薄壁圆筒车削仿真过程的影响,利用Abaqus软件和AdvantEdge软件对薄三维模型以及薄壁圆筒模型的车削过程进行了对比分析,同时以主切削力和切屑形态为指标对切削仿真质量进行了评价。结果表明:在保证薄三维切削仿真精度的前提下,六面体网格可以极大地节省计算时间,更好地反映切削过程中的切屑形态和已加工表面质量等物理量的变化;航空薄壁圆筒车削仿真中采用扫略网格画法可以在一定程度上提高计算效率和工件表面质量。 相似文献
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Myeong-Jin Lee Young-Ju Jeon Ga-Eun Son Sihwa Sung Ju-Young Kim Heung Nam Han Soo Gyeong Cho Sang-Hyun Jung Sukbin Lee 《Metals and Materials International》2018,24(4):845-859
We present a new comprehensive scheme for generating grain boundary conformed, volumetric mesh elements from a three-dimensional voxellated polycrystalline microstructure. From the voxellated image of a polycrystalline microstructure obtained from the Monte Carlo Potts model in the context of isotropic normal grain growth simulation, its grain boundary network is approximated as a curvature-maintained conformal triangular surface mesh using a set of in-house codes. In order to improve the surface mesh quality and to adjust mesh resolution, various re-meshing techniques in a commercial software are applied to the approximated grain boundary mesh. It is found that the aspect ratio, the minimum angle and the Jacobian value of the re-meshed surface triangular mesh are successfully improved. Using such an enhanced surface mesh, conformal volumetric tetrahedral elements of the polycrystalline microstructure are created using a commercial software, again. The resultant mesh seamlessly retains the short- and long-range curvature of grain boundaries and junctions as well as the realistic morphology of the grains inside the polycrystal. It is noted that the proposed scheme is the first to successfully generate three-dimensional mesh elements for polycrystals with high enough quality to be used for the microstructure-based finite element analysis, while the realistic characteristics of grain boundaries and grains are maintained from the corresponding voxellated microstructure image. 相似文献
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HEXAHEDRAL ELEMENT REFINEMENT FOR THE PREDICTIONCORRECTION ALE FEM SIMULATION OF 3D BULKING FORMING PROCESS 总被引:1,自引:0,他引:1
J.Chen Y.X.Wang W.P.Dong X.Y.Ruan 《金属学报(英文版)》2004,17(6):923-927
Based on the characteristics of 3D bulk forming process, the arbitrary Lagrangian-Eulerian (ALE)formulation-based FEM is studied, and a prediction-correction ALE-based FEM is proposed which integrates the advantages of precisely predicting the boundary configuration of the deformed material, and of efficiently avoiding hexahedron remeshing processes. The key idea of the prediction-correction ALE FEM is elaborated in detail. Accordingly, the strategy of mesh quality control, one of the key enabling techniques for the 3D bulk forming process numerical simulation by the prediction-correction ALE FEM is carefully investigated, and the algorithm for hexahedral element refinement is formulated based on the mesh distortion energy. 相似文献
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I.H. Son Y.W. Han H.S. Kim Y.T. Im 《Journal of Materials Processing Technology》2003,140(1-3):465-470
In finite element simulations of forming processes with a complex geometry, free surface folding phenomenon is likely during simulations when die design or the size of initial billet is inappropriately determined. In such cases, free surface geometry becomes so acute that mesh generation may be impossible with a conventional looping technique automatically. In order to solve this kind of problem, looping technique was modified to generate boundary elements for the acute geometry with a better mesh quality. The developed technique was implemented to the in-house bulk metal forming simulation program CAMPform and applied for forming simulations of ring gear forging and nosing in which surface folding defects occur. It was found that folding phenomenon was successfully handled with the currently developed algorithm and suitable process conditions to eliminate the free surface folding were determined through numerical simulations. 相似文献