大型轴流式叶片曲面的反求与重构建模

数字化模型是叶片式流体机械数字化设计与制造的基础,根据大型轴流式水轮机叶片的特点,提出了基于反求技术的大型轴流式水轮机叶片曲面重构方法。采用三坐标测量机测得叶片实体模型的表面数据,通过对点云数据进行平滑、精简处理,使用点云网格化、曲面特征提取,曲面分割及拟合曲面片的曲面重构技术,快速、精确地拟合出叶片曲面模型,提高了建模的精度和效率,为后续数字化设计与制造研究奠定了基础。

3D Measurement and Surfaces Reconstruction Modelling of Large Size Blade of Axia Flow Type

The digital model is the base of blade type fluid machinery digitized design and manufacture.According to the large axial flow type hydraulic turbine characteristics,reverse technology of large axial flow turbine blade surface reconstruction method is presented.Three coordinate measuring machine is adopted to obtain the surface data of the blade model.The reconstruction of 3D geometrial surfaces of blade were realized through such processing procedures as smoothing and sampling point cloud data,gridding of the point data,extraction of surface feature,partition of surfaces and directly fitting surface partition.This method which realizes the rapid and precise modeling of hydroturbine blade,could serve as a basis for the further digital design and manufacturing research.