侧风下孤立尾桨的气动特性和抗侧风优化  

Aerodynamic characteristics and crosswind counteraction of isolated tail rotor in crosswind environment

作　　者：孙钰锟 王珑[1] 王同光[1] 钱耀如 郑全伟 SUN Yukun;WANG Long;WANG Tongguang;QIAN Yaoru;ZHENG Quanwei(Jiangsu Key Laboratory of Hi-Tech Research for Wind Turbine Design,Nanjing University of Aeronautics and Astro-nautics,Nanjing 210016,China;Energy Research Institute,Nanjing Institute of Technology,Nanjing 211167,China)

机构地区：[1]南京航空航天大学江苏省风力机设计高技术研究重点实验室,南京210016 [2]南京工程学院能源研究院,南京211167

出　　处：《航空学报》2023年第10期60-76,共17页Acta Aeronautica et Astronautica Sinica

基　　金：国家重点研发计划(2019YFE0192600,2019YFB1503700);国家自然科学基金(52006098);江苏高校优势学科建设工程资助项目;南京工程学院基金(YKJ201943)。

摘　　要：尾桨涡环严重危害了直升机飞行安全,为探讨涡环对桨盘附近诱导速度场的影响和解释桨叶拉力非定常脉动的原因,构建了一套基于非定常雷诺平均Navier-Stokes方程的尾桨涡环数值计算方法,并结合叶素动量理论和圆线涡环模型进行气动分析。同时,为解决当前翼型优化中广泛使用的冻结湍流黏性假设存在的固有缺陷,建立了一套全湍流连续伴随的翼型优化框架,获得的翼型用于尾桨设计以提高尾桨抗侧风能力。结果表明,桨盘附近诱导速度场对侧风入流速度十分敏感,在典型涡环状态下,14.65 m/s侧风导致涡环的涡强增大且不断改变,引发翼剖面的有效攻角随桨盘附近风速动态减小,进而尾桨拉力下降至原有的58.5%并伴有高频脉动。全湍流连续伴随在最优外形的获取上则要领先于冻结湍流黏性假设,最佳翼型获得的尾桨相较于原始尾桨的拉力提高了10.9%,悬停效率提高了3.9%,扩大了尾桨进入涡环的临界侧风速度。The tail rotor vortex ring seriously endangers the flight safety of helicopters.To explore the influence of the vortex ring on the induced velocity field near the rotor disk and explain the cause of unsteady pulsation of blade thrust,we construct a set of numerical calculation methods for the tail rotor vortex ring based on unsteady Reynolds averaged Navier Stokes equations,and conduct aerodynamic analysis combining the blade element theory and the circular vor⁃tex ring model.Meanwhile,an airfoil optimization framework with the continuous adjoint turbulence is established to solve the inherent defects of the frozen eddy viscosity assumption,and the obtained airfoil is used in the design of tail rotors to improve the crosswind counteraction ability.The results show that the induced velocity field near the propeller disk is sensitive to the inlet velocity of the cross wind.In the typical vortex ring state,the cross wind of 14.65 m/s causes the vortex strength of the vortex ring to increase and change continuously,induces decrease and dynamic change of the effective angle of attack of the blade section,and further reduces the tail rotor thrust to 58.5%of the original value with high-frequency pulsation.The adjoint turbulence method is superior to the frozen eddy viscosity as⁃sumption in terms of optimization convergence.Compared with those of the base tail rotor,the thrust of the tail rotor obtained by optimizing the airfoil and the figure of merit are increased by 10.9%and 3.9%,respectively,and the criti⁃cal crosswind velocity of the tail rotor entering the vortex ring is expanded.

关 键 词：侧风环境 尾桨涡环 尾桨抗侧风 翼型优化 全湍流伴随 

分 类 号：V275[航空宇航科学与技术—飞行器设计]