摘要
为研究仿生波状前缘对翼型失速性能的影响,本文采用S-A湍流模型,对风力机翼型NACA634-021(光滑前缘)以及对应的正弦波状前缘仿生翼型的绕流流场进行了数值模拟。结果表明,光滑翼型在20°攻角附近发生深度失速,升力系数骤然下降;而波状前缘仿生翼型有效改善了失速特性,升力系数变化较平稳,在大攻角下高于光滑翼型。通过流场分析发现光滑翼型失速前后升力系数骤然下降的主要原因在于前缘压力面和吸力面的压差大幅度下降,而仿生翼型改变了前缘的压力分布特性,进而改变了大攻角下的分离特性,促进流向涡对的产生和发展,使得凸峰附近保持附着流动,进而提高升力。
In order to investigate the influence of the wavy leading edge on the airfoil stall performance,numerical simulations were carried out to analyze the flow field around a basic NACA63_4-021 airfoil and a modified airfoil with wavy leading edge using S-A turbulence model.The results show that wavy leading edge can improve the stall characteristic effectively,especially raise the lift coefficient at high angles of attack.The bionic airfoil with wavy leading edge has a different separation characteristic,which keeps an attached flow around the convex cross section in the post-stall region.The reason for the decline of lift coefficient before and after the stall was found to be the significant decline of the pressure gradient around the leading edge,and the bionic structure can help improve the pressure distribution in a high angle of attack.A couple of streamwise vortices were discovered on both sides of the convex cross section,which might promote the attached flow around the convex section.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2015年第3期531-534,共4页
Journal of Engineering Thermophysics
关键词
风力机翼型
波状前缘
失速特性
数值模拟
airfoil
wavy leading edge
stall characteristic
numerical simulation
