平流层飞艇三叶螺旋桨结构优化方法

Structure optimization method of three-blade propeller for stratospheric airship

为实现螺旋桨轻质量和高固有频率之间的权衡设计,发展了1种桨叶对称削层结构的分区优化方法。为拓宽其高效率的速度和高度范围,应采用变桨距技术,需要设计圆柱形桨叶根部。该桨叶与不同桨距角的桨毂组合装配,可实现人工变桨距,在地面试验中达到高空转速。该螺旋桨采用组合分体式桨毂布局、桨叶内部填充泡沫和碳纤维混合结构,基于NSGA-Ⅱ(non-dominated sorting genetic algorithm),完成了支座固支的桨叶铺层参数优化,得到桨叶质量和频率的Pareto解集,在±10%频率安全裕度外选取最优铺层方案,并与实物测试值对比,结果表明:桨叶质量相对误差2.09%;支座固支的单桨叶频率相对误差9.30%;桨毂固支的组合体频率相对误差2.76%,避开了工作转速共振区间,证明该结构优化方法是合理有效的。

In order to achieve propeller’s trade-off design between light mass and high natural frequency,a partition optimization method of symmetrical cutting layer structure for its blade was developed.For broadening its speed and height range of high efficiency,variable pitch technology should be adopted,and cylindrical blade root should be designed.The blades were assembled with the hub of different pitch angles,which can realize manual variable pitch and reach the high altitude rotate speed in ground test.A combined split hub layout,foam-filled form inside the blades,and carbon fiber hybrid structure in the propeller were adopted,the laying parameters optimization of fixed-supported propeller blades was finished based on the NSGA-Ⅱ(non-dominated sorting algorithm),and Pareto solution set of blade mass and frequency was obtained.The optimal laying scheme was selected outside the±10%of frequency safety margin,and compared with test values of the actual prototype.The results showed that the relative error of blade mass was 2.09%,the relative error of single blade frequency on fixed support was 9.30%,and the relative error of the combined frequency of three blades and the hub on fixed support was2.76%.This avoided resonance region of the working rotate speed,proving that the structure optimization method is reasonable and effective.