中文摘要：

为解决几何插值和逼近给定型值点的拟合方法不满足流线型特性的问题,提出一种面向叶型和翼型的考虑流线场约束的NURBS曲线拟合方法.首先以型值点处精度和连续性作为几何约束;之后采用升力最大作为物理约束,根据空气动力学理论推导出NURBS形式的升力解析表达式;最后通过优化的方法求解拟合模型.程序实例和CFD仿真结果表明,文中的流线型曲线拟合方法可用于流线型曲线造型,与纯几何的拟合方法相比,能够得到工作性能更优的NURBS曲线.

英文摘要：

The classical geometrical fitting,which only use the interpolation and approximation to fit thegiven data points,cannot satisfy the streamline constraint.An improved NURBS curve fitting method forturbine blade and airfoil profile was proposed by considering constraint of streamline field.The constraintsinclude the accuracy and continuity at the data points,which are used as the geometrical constraints,and themaximal lift as the physical constraint.The NURBS-formatted analytical expression of the lift,deducedfrom the aerodynamics,is solved to obtain the fitting model by using the optimization method.The casestudy and CFD simulation demonstrate that the new NURBS curve fitting method with the streamline constraintcan improve the working performance compared with the geometrical fitting method.