中文摘要：

流线族（SSL）作为复杂高精度径流式叶轮（RIT）的关键几何元素,对于RIT的建模和气动优化有着非常重要的作用。以RIT的多学科耦合设计为目标,研究了面向型面和特征的联合采集方法以获取RIT表面信息;基于线几何理论,提出了RIT直纹叶片子午流道几何（MS）及直母线矢量（SGVs）的提取方法;探讨了直纹母线矢量的等分算法;研究了可同时控制光顺和逼近程度的叶片型面流线族的拟合方法;建立起以SSL和子午流道几何为参数的径流式叶轮参数化模型,实现对任意RIT样件的SSL自动提取及叶轮的自动参数化建模,通过实例验证了该方法的有效性和可行性。

英文摘要：

A set of streamlines （SSL）, as a significant geometric element in complex radial-inflow turbomachinery （RIT） with high precision, plays a vital role in modeling and aerodynamic optimization of RIT. Aimed at multidisciplinary design of RIT, we develop an integrated acquisition method oriented towards the profile and characteristics of RIT to obtain the surface information of RIT. An extraction method of the meridional section （MS） and straight generatrix vectors （SGVs） of the RIT with the ruled surface is proposed based on line geometry theory. The division algorithm of SGVs is anlayzed. A method for SSL fitting is presented to control both the smoothing and approximation degree of the blade surface. A parametric model of RIT is established by using SSL and MS as parameters to realize automatic extraction of SSL from arbitrary RIT prototype and automatic parametric modeling of the impeller. A case example is given to demonstrate the effectiveness of the pro- posed strategy.