基于定常吸气的翼型动态失速特性研究

RESEARCH ON DYNAMIC STALL CHARACTERISTICS OF AIRFOIL BASED ON STEADY SUCTION

翼型动态失速过程易在吸力面产生大尺度涡脱落,导致发生失速造成气动性能急剧下降。采用滑移网格及SST k-ω湍流模型对S809翼型开展数值模拟,研究前缘定常吸气对其动态失速流动控制效果及气动特性的影响。结果表明:吸气可有效抑制动态失速涡脱落,增大翼型吸/压力面两侧压差,并提高其气动性能;距翼型前缘0.05c处进行定常吸气可获得最大平均升力系数,吸气位置靠近前缘时,修正阻力系数减小;当吸气动量系数为0.025、吸气距前缘0.15c时,修正升阻比在所研究攻角内较原始翼型提升最大;吸气耗能与吸气动量系数成正相关,且随吸气缝距前缘位置减小而增大。

Large-scale vortex shedding is prone to occur on the suction surface during dynamic stall process of the airfoil,resulting in a sharp decline in aerodynamic performance due to stall.Numerical simulation of the S809 airfoil is carried out by using sliding mesh technology and SST k-ωturbulence model,and the effect of the leading-edge steady suction is studied on dynamic stall flow control and aerodynamic characteristics.The results show that the suction effectively suppresses the dynamic stall vortex shedding,increases the pressure discrepancy on both sides of the suction/pressure surface and improves the aerodynamic performance.The maximum average lift coefficient can be obtained by steady suction at 0.05c from the leading-edge of the airfoil,while there is sustained decrease of the corrected drag coefficient as the suction position closing to the leading-edge.When the suction momentum coefficient is 0.025 and the suction distance from the leading-edge is 0.15c,the corrected lift-drag ratio is largest in the studied angle of attack compared with the original airfoil.Moreover,suction energy consumption is positively correlated with the suction momentum coefficient,increasing with the decrease of the suction gap distance from the leading-edge.