共轴式刚性双旋翼悬停气动载荷CFD仿真分析  

CFD simulation analysis of the hovering aerodynamic load of rigid coaxial twin rotors

作　　者：石力王 胡明辉[1,2] 陈广艳 陈伦国 石万凯[1,2] 曾利[1] SHI Liwang;HU Minghui;CHEN Guangyan;CHEN Lunguo;SHI Wankai;ZENG Li(College of Mechanical and Vehicle Engineering,Chongqing University,Chongqing 400044,China;State Key Laboratory of Mechanical Transmissions,Chongqing University,Chongqing 400044,China;AECC Hunan Aviation Powerplant Research Institute,Zhuzhou 412000,China;National Key Laboratory of Defence Science and Technology on Helicopter Transmission,Zhuzhou 412000,China)

机构地区：[1]重庆大学机械与运载工程学院,重庆400044 [2]重庆大学机械传动国家重点实验室,重庆400044 [3]中国航发湖南动力机械研究所,湖南株洲412000 [4]直升机传动技术国防科技重点实验室,湖南株洲412000

出　　处：《重庆理工大学学报（自然科学）》2022年第11期167-175,共9页Journal of Chongqing University of Technology：Natural Science

摘　　要：为探究共轴式刚性双旋翼的上下旋翼总距差与气动载荷的关系,平衡上下旋翼力矩差,从而提高双旋翼系统稳定性,以直升机的共轴式刚性双旋翼为研究对象,应用非结构运动嵌套网格技术及计算流体力学(CFD)方法开展直升机共轴式刚性双旋翼在悬停状态下的气动载荷分析研究。计算结果表明:下旋翼浸没于上旋翼产生的下洗流中,导致下旋翼的气动性能降低,下旋翼拉力低于上旋翼;在保持下旋翼总距角不变的情况下,随上下旋翼总距差的增大,上旋翼拉力与力矩出现先减后增再减的现象,而下旋翼拉力与力矩则一直呈增大趋势;为实现上下旋翼力矩平衡,通过调整上旋翼总距角,分析了上下旋翼总距差在-1°~0°时上下旋翼气动载荷的变化规律,确定了最佳上下旋翼总距角分别为5.6°和6.0°,实现对双旋翼的力矩平衡。In order to explore the relationship between the collective pitch difference of the upper and lower rotors and the aerodynamic load of rigid coaxial twin rotors,researchers balance the torque difference between the upper and lower rotors,thereby improving the stability of the twin rotor system.This thesis takes the rigid coaxial twin rotors of helicopters as the research object,and uses the unstructured motion-embedded grid method and computational fluid dynamics(CFD)method to carry out the aerodynamic load analysis of the helicopter rigid coaxial twin rotors in hovering conditions.As the calculation results show,the lower rotor is immersed in the downwash flow generated by the upper rotor,resulting in a decreasing aerodynamic performance of the lower rotor,and the pull force of the lower rotor is lower than that of the upper rotor;under the condition that the collective pitch angle of the lower rotor remains unchanged,as the collective pitch difference between the upper and lower rotors increases,both the pull forces and the torque of the upper rotor decrease first,then increase and finally decrease again,while both the pull forces and the torque of the lower rotor always show an increasing trend;in order to achieve the balance between the upper and the lower rotor torques,the collective pitch angle of the upper rotor is adjusted to analyze the variation law of the aerodynamic load of the both rotors when the collective pitch difference is in the range of-1°~0°.In this case,the best collective pitch angles of the upper and the lower rotors prove to be 5.6°and 6°respectively,thus achieving torque equilibrium for twin rotors.

关 键 词：共轴式刚性双旋翼 气动特性 运动嵌套网格 CFD 总距角 总距差 

分 类 号：V211[航空宇航科学与技术—航空宇航推进理论与工程]