摘要
为实现存在裁剪、孔洞的复杂自由曲面建筑网格划分,提出了一种基于离散的、以均匀性为目标的划分方法.将复杂曲面离散并缝合,形成由大量面片组成的离散曲面,作为多个参数曲面的一体化表示.采用改进的误差扩散算法,在离散曲面上按一定的密度进行初始布点.采用基于空间距离的粒子动力松弛算法对点云进行初步均匀化,并应用基于曲面距离的k均值算法进行再次均匀化.对均匀的点云求曲面距离的Voronoi图,并获得相应网格.对网格进行拓扑优化和光顺优化.算例表明,本文算法可有效处理存在裁剪、孔洞的复杂自由曲面,并得到均匀光顺的三角网格.
A grid generation method for complicated multiple surfaces with trimmings and holes is presented. This method is based on the discretization and concentrates on the aim of homogeneity. The multiple surfaces are discretized separately and seamed together to achieve a discrete surface. The points are distributed on the discrete surface according to the density applying improved error-diffusion method. The points are homogenized by particle dynamics method with Euclid distance and then homogenized once more by k-means algorithm with surface distance. The Voronoi diagram with surface distance is delivered on the discrete surface to obtain the grids. The topological and smooth relaxations are applied on the grids. Eventually, the case study indicates that this method can solve the problem of grid generation for complicated multiple surfaces effectively and achieve the homogeneous and smooth grids.
引文
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