船舶螺旋桨尾流场的数值分析

Numerical analysis of the flow field around marine propellers by surface panel method

利用基于速度势的低阶面元法计算船舶螺旋桨的尾流场。采用计算较为简捷的关于扰动速度势的基本积分微分方程 ,并采用双曲面形状的面元以消除面元间的缝隙。Newton -Raphson迭代过程被用来在桨叶随边满足压力Kutta条件 ,使桨叶上下表面的压力在随边有良好的一致性。在计算面元的影响系数时 ,应用了Morino导出的解析计算公式 ,加快了数值计算的速度。从解面元法的基本积分方程得到的偶极强度和源汇强度 。

The potential based low order surface panel method is used to calculate the flow field behind marine propellers. In the present method the hyperboloidal quadrilateral panels are employed to avoid the gaps between the panels. The influence coefficients of panels are determined by Morino's analytical formulations for increasing numerically calculating speed. The pressure Kutta condition is satisfied on the trailing edge of propeller blade by Newton-Raphson iterative procedure. Therefore the pressure coefficients of the suction and pressure faces of blade are equal on trailing edge. By solving the fundamental integral equation in panel surface method, the intensities of doublets and sources on the surface of marine propellers can be obtained. With these doublets and sources the velocity distributions in the flow field behind marine propellers are derived. The flow fields of two propellers are calculated and the results are compared with the experimental data.