基于自由尾迹方法的共轴式双旋翼流场分析  

Flow Field Analysis of Coaxial Twin Rotors Based on Free Wake

作　　者：黄水林[1] 徐国华[1] 李春华[1] 

机构地区：[1]南京航空航天大学航空宇航学院,南京210016

出　　处：《南京航空航天大学学报》2008年第6期721-726,共6页Journal of Nanjing University of Aeronautics & Astronautics

基　　金：高等学校博士学科点专项科研基金(20050287028)资助项目

摘　　要：建立了一个适合于共轴式直升机双旋翼流场特性分析的自由尾迹计算方法。该方法中,桨叶模型采用了升力面/涡格法,尾迹则使用畸变的自由尾迹模型,以更好地模拟流场特性及计入桨尖三维效应。通过旋翼下洗速度的计算值与可得到的实验值对比,表明了该计算方法的有效性。然后,着重计算分析了共轴式直升机的旋翼尾迹结构和诱导速度分布,并与单旋翼情况进行了对比。结果表明:悬停时,与单旋翼相比,共轴式双旋翼在旋翼下方的诱导速度更大,但并非两幅单旋翼诱导速度的迭加;前飞时,随前飞速度的增加,上下旋翼间的相互干扰逐渐减弱。A computational method based on rotor flee-wake is developed for predictig flow field between the twin rotors of coaxial helicopters. The analytical method combines a lifting-surface/vortex-lattice blade model with a flee-vortex wake model to simulate the rotor flow field and 3-D tip effects. The com- parison between the calculated results and available experimental data validates the computational method. Then, aerodynamic interactions between the coaxial rotors are calculated and analyzed on wake geometries and the induced velocities, the single and coaxial rotors are compared. Results show that the induced velocity of coaxial rotors below the rotor in hover is larger than that of the single rotor, but not the sum of two single rotors. And the aerodynamic interaction between upper rotor and lower rotor weakens with the increase of the velocity in forward flight.

关 键 词：旋翼 直升机 自由尾迹 共轴式旋翼 流场 

分 类 号：V211.52[航空宇航科学与技术—航空宇航推进理论与工程]