【摘要】 冲击式水轮机的水斗是具有三维自由曲面的几何体,在曲面贴体网格(BFG)上,为了正确分析冲击式水轮机的流动,有必要引用非正交曲线坐标系。本论文介绍了如何得到边界贴体网格点的自然基本矢量g。在计算基本矢量的过程中,对三个特殊点进行了研究。对这些点的自然坐标矢量运用对角线进行了重新定义,计算后得到了理想的计算结果。更多还原

【Abstract】 Since a Pelton bucket has the geometry of complicated 3-D free-curved surface,it is necessary to apply the non-orthogonal curvilinear coordinate system for the boundary-fitted grids (BFG)to perform the accurate flow analysis of Pelton turbines.This paper presents how to acquire the natural basis vector g at the each grid node of the given BFG.Through the process of acquiring g, we found that there are three singular nodes on a boundary curve of the bucket brim.Special attention was required to obtain the reliable natural basis vectors for the singular nodes to complete a whole BFG.更多还原