立式捏合机搅拌桨曲面的NURBS表示与误差分析

摘要

依据搅拌桨水平截面轮廓线的理论坐标点,反求生成了NURBS曲线；按照搅拌桨的螺旋升角,生成了一组不同高度截面轮廓线的NURBS曲线；利用蒙皮方法,生成了搅拌桨的NURBS曲面.提出了一种新的控制顶点投影法求解点到NURBS曲面最小距离的算法,用于计算搅拌桨的NURBS曲面的重构误差.结果表明,立式捏合机搅拌桨的NURBS曲面重构精度高,研究结果可为搅拌桨曲面优化设计提供借鉴.%According to the theoretical points of stirring blade horizontal sectional contour curve,a NURBS sectional curve was generated in reverse. Based on the helix angle of stirring blade, a set of different height NURBS sectional curves were produced. Using skinning surface method, the stirring blade NURBS surface was formed. The projection method of control points was proposed for calculating the minimum distance between a point and NURBS surface, to obtain the reconstruction errors of stirring blade NURBS surface. The results show that the NURBS surface reconstruction precision of vertical kneader stirring blade is high, which lays a good foundation for future stirring blade optimization design.