大侧斜螺旋桨水动力性能预报

Prediction of Hydrodynamic Performance of Highly Skewed Propeller

采用面元法预报大侧斜螺旋桨水动力性能 ,螺旋桨表面及尾涡面离散为四边形双曲面元 ,每个面元上布置等强度源汇和偶极子分布 .对于大侧斜螺旋桨而言 ,桨叶表面采用常规的等半径网格划分方法在近叶梢处将导致大展弦比、大侧斜和扭曲面元 ,这容易使桨叶表面速度的计算结果不正确 ,甚至会导致迭代过程发散及计算失败 .文中建立了一种“非常规网格”划分方法 ,能有效地解决大侧斜螺旋桨的计算和收敛问题 .

The surface panel method has been applied to predict the hydrodynamic performance of highly skewed propeller.The surface of propeller and its trailing vortex are discreted by a number of small hyperboloidal quadrilateral panels with constant source and doublet distribution.For highly skewed propeller,the conventional method generating grid oriented along constant radii will result in a high aspect ratio and a high skewness and a twist panel near the propeller tip on blade surface,which result easily in incorrect calculation results of velovity on blade surface,even in iteration divergence and calculation failure.A “non conventional grid” is developed to acoid these problems.This grid can effectively solve the problem of the calculation and convergence for highly skewed propeller.The non linear Kutta condition of equal pressure on upper and lower at the trailing edge is executed by the iterative procedure.By sample calculating,the obtained results are satisfied the experimental data.