基于Eppler剖面设计方法上的提高空泡起始航速的非定常螺旋桨设计方法

为了提高螺旋桨的空泡起始航速，本文提供了一个基于Eppler剖面设计方法上的非定常螺旋桨设计方法，二维剖面直接由Eppler剖面设计方法给出并直接输入到升力面设计程序中进行三维剖面设计。计算结果表明新剖面螺旋桨方案的空泡斗要比常规剖面的宽。在平均伴流条件下使用升力线、升力面设计程序给出一个初步螺旋桨方案。然后用定常/非定常面法检查设计结果是否满足推力要求并作修改设计，从中选择一个不符合空泡要求的剖面作为关键剖面。使用Eppler剖面设计方法来改善空泡斗，为了研究剖面弦向负荷对螺旋桨性能影响，本文设计两只螺旋桨，一只为带有Naca66迭加Naca a=0.8，另一只为新剖面的方案。模型试验结果证实了设计方法的有效性。

A Propeller Design Method with New Blade Section for Improving Cavitation Inception under Unsteady Condition

A propeller design procedure for improving cavitation inception in non-uniform inflow is presented. Special attention is paid to the design of blade sections with Eppler method, in order to behave higher cavitation inception speed. The two-dimensional section directly obtained by Eppler method is converted into a new blade section in three-dimensional case since they are significantly different from each other. Calculations show that the cavitation-free bucket diagram of new blade sections is wider than the conventional NACA sections.The lift-line and lift-surface methods are used for the initial propeller design with the circumferential averaged inflow. Using steady/unsteady panel method to check and to modify the design for meeting the thrust requirement and selecting a key section suffering from cavitation. New blade sections are adopted to improve the cavitation bucket. To investigate the influence of the chordwise loading distribution forms on the propeller performance, two propellers with different chordwise loading are designed. Their model test results confirm the effectiveness of the design method.