摘要
为研究湍流度对低雷诺数翼型气动特性的影响,采用经过风洞试验验证的基于γ--R--e-θt转捩模型的RANS数值模拟方法,针对典型低雷诺数翼型E387,选取不同雷诺数/湍流度状态开展了对比分析。研究结果表明,湍流度对翼型气动特性的影响十分显著且规律较为复杂。高湍流度可以在一定状态下使升阻比大幅提升,显著改善低雷诺数翼型的气动性能。失速前小迎角时通常受低雷诺数流动特有的层流分离泡结构影响,大迎角失速后主要受后缘分离影响,气动规律的复杂性与这两种主导因素受湍流度影响后的演化与转换密切相关。低雷诺数/高湍流度和高雷诺数/低湍流度的升阻特性与流场结构具有相似性,利用有效雷诺数方法可以对该相似性作定量分析。
In order to investigate the influence of turbulence intensity on the aerodynamic characteristics of low Reynolds number airfoil,the RANS numerical simulation method based on transition model,which has been verified by wind tunnel test.For the typical low Reynolds number airfoil E387,different Reynolds number and turbulence intensity states are selected for aerodynamic analysis.The results show that the turbulence intensity has a significant effect on the aerodynamic characteristics of the airfoil and the phenomena are comparatively complicated.Under certain conditions,high turbulence intensity can enhance the lift-drag ratio of the low Reynolds number airfoil,significantly improving its aerodynamic performance.Usually at small AoAs before stall,it is largely affected by the laminar separation bubble.While at high AoAs after stall,it is ascribed to the trailing edge separation.The complex phenomena of aerodynamic changes are attributed to the influence of turbulence on these two dominant factors.The similarity of lift/drag characteristics and flow structure between low Re/high Tu and high Re/low Tu is demonstrated,the method of effective Reynolds number can quantitatively analyze such similarity.
作者
李帝辰
魏闯
张铁军
杨威
Li Dichen;Wei Chuang;Zhang Tiejun;Yang Wei(Aero Science Key Lab of High Reynolds Aerodynamic Force at High Speed,AVIC Aerodynamics Research Institute,Shenyang 110034,China;Beijing Research Institute of Mechanical&Electrical Engineering,Beijing 100074,China)
出处
《航空科学技术》
2022年第2期12-21,共10页
Aeronautical Science & Technology
关键词
低雷诺数
湍流度
翼型绕流
转捩模型
有效雷诺数
low Reynolds number
turbulence intensity
airfoil flow
transition model
effective Reynolds number
