螺旋桨桨叶根部断裂飞脱轨迹数值仿真

Numerical Simulation of Fly-off Trajectory of Root-Fractured Propeller Blade

螺旋桨桨叶断裂飞脱轨迹对飞机的安全性有重要的影响。为了研究螺旋桨桨叶根部断裂后的运动过程,采用数值模拟方法进行了仿真分析,并与风洞试验结果对比。将求解区域划分为10个网格区域,对其中3个螺旋桨旋转区域单独划分网格,通过滑移网格进行数据传递,对有飞脱桨叶的螺旋桨的6个桨叶分别设置重叠网格。采用螺旋桨真实旋转的非定常方法获得周期性稳定的空间流场,当飞脱桨叶到达指定位置后,求解桨叶的6自由度运动方程,计算桨叶的飞行轨迹。结果表明:在短时间内,该螺旋桨的桨叶飞脱后的运动轨迹主要受惯性力的影响,而气动力的影响不大;飞脱桨叶的桨根在第0.015 s左右与后继桨叶的桨尖相撞,与测力风洞试验的断桨事故诊断结果相符。

The fly-off trajectory of a fractured propeller blade has a significant impact on aircraft safety.A numerical investigation of the fly-off trajectory of the root-fractured propeller blade was conducted and compared with the wind tunnel test results.The computational domain was divided into ten grid subdomains,grids were generated separately for each of the three propeller rotation subdomains,data were transferred through sliding grids,and subdomains containing the six blades of the propeller with the fly-off blade were set with overlapping grids respectively.The unsteady method of real rotation of the propeller was adopted to obtain a periodic and stable flow field.When the fly-off blade reaches the specified position,the six-degree-of-freedom motion equation of the blade is solved to calculate the fly-off trajectory of the blade.The results show that in a short period of time,the trajectory of the propeller blade after flying off is mainly affected by the inertial force,the aerodynamic force has little effect on the trajectory,and the root of the detached blade collided with the tip area of the subsequent blade at about 0.015 seconds.which is consistent with the diagnostic results of the broken propeller blade accident in the force-measuring wind tunnel test.