非均匀有理B样条曲线及节点插入算法在透平叶片优化设计中的应用

Application of non-uniform rational B-spline curve and knot insertion algorithm to turbine blade optimization

将非均匀有理B样条(NURBS)曲线及节点插入算法应用到透平叶栅的二维参数化造型,可以兼顾造型参数的实际物理意义和型线调节的灵活性;将控制点可调的NURBS曲线应用到三维叶片积叠线造型,能够构造任意形状的弯、扭、掠叶片.在此基础上搭建的透平叶片三维气动优化平台,将参数化造型、网格自动划分、流体计算并行求解集成在一起,应用实验设计和响应面分析方法进行多目标寻优.对某单级实验透平分别进行单排叶片和整级优化后,单排叶片总压损失降低了0.57%;单级绝热效率提高了0.8%.

Non uniform rational B-spline （NURBS） curve and knot insertion algorithm were used for parametric modeling of turbine blade profiles, in which actual physical meaning of the parameters and flexibility of profile regulation can be taken into account. Bended, twisted and swept blades were successfully constructed by applying NURBS with adjustable number of control points to stacking line modeling. An aerodynamic optimization platform for three-dimensional turbine blade has been developed, in which the parametric modeling, grid generation, computational fluid dynamics analysis and multi-objective optimization based on design of expert （DOE） and response surface method （RSM） method were integrated. After optimization, the total pressure loss of a single-row turbine cascade was reduced by 0.57% and the adiabatic efficiency of a singe-stage turbine was increased by 0.8 %.