摘要
基于k-ω的SST两方程湍流模型,在时间域求解雷诺平均Navier-Stokes方程(RANS)计算了翼型大迎角分离流动。通过给翼型施加不同形式的扰动,重点关注了不同扰动形式对翼型大迎角分离涡流场平衡态的影响。研究表明:在所给定的百万雷诺数条件下,当翼型厚度达到一定程度而且在一定迎角范围内时,翼型的分离涡流场存在多个平衡态,且在一定扰动条件下会发生平衡态转移现象。在不同振动形式上,沉浮和俯仰比前后振动更易激发平衡态的转移。正是这种分离涡流场平衡态的多值现象,可能引发风洞实验中大迎角气动力数据的分散。
The Reynolds-Averaged Navier-Stokes （RANS） method is conducted to simulate flow around airfoil at high AOA. The separation is well captured using two-equation shear stress transport （SST/k-w） turbulence model accounting for turbulence motions. Calculation shows that the wing separation vortices are stable in several equilibrium stats, with the wing thickness up to a certain criteria, and AOA in a certain range. Meanwhile the separation transfers from one stable state to anther when certain disturbance is intruded. Comparing different disturbances, the translation is inclined to happen under heaving-pitching motions rather than forward-afterward vibrations. That is the exact one of most important reasons for aerodynamic loads data variation of airfoil at high AOA in wind tunnel test.
出处
《空气动力学学报》
EI
CSCD
北大核心
2012年第4期477-482,共6页
Acta Aerodynamica Sinica
关键词
分离流
稳定性
重复性
separated flow
stability
repeatability
