组合合页式扑翼在悬停状态下的三维仿真分析

通过观察鸟类扑翼飞行的运动特征,研究了一种新型组合合页式扑翼推进技术.介绍了组合合页式扑翼推进技术的基本原理,建立了其运动学和动力学模型;在此基础上,通过联合求解动力学方程和三维纳维斯托克斯方程,对组合合页式扑翼在恒定速度下的低频大行程往复运动进行仿真,以分析组合合页式扑翼在2自由度运动时的运动特征和空气动力学特性.结果表明:所提出的扑翼推进方式在悬停状态下能够产生持续的正升力;在相同的往复速度下,增大运动行程可以降低1个周期内过渡状态所占的比例,但平均升力系数随之减小;当运动频率约为2Hz时,其平均升力系数可以达到3.0以上.

Three Dimensional Simulation ofthe Modular Hinge Type Wings in Hovering Flight

This paper describes the design and analysis of a new propulsion technology, which is inspired by the motion feature of the bird’s feathers. Both the structural models and its flapping wings of the bio inspired propulsion are established. The dynamic equation and three dimensional Navier Stokes equations are solved to acquire motion features and mechanical properties. Then, the aerodynamic performance of the wings for the propulsion which reciprocates at a constant speed is achieved though the analysis of the flow field characteristics. The flow distributions of the modular hinge type wings in some typical moments are studied. The lift coefficients, the angle between blades and yOz plane, the angular velocity of the blades for different exercise frequency are further discussed. The results indicate that this type of propulsion can provide an efficient propelling force when wings are flapping at a low frequency by reciprocating in long travel. The average lift coefficient in a moving cycle would keep above 3.0 when the frequency is 2Hz.