边条翼后掠角对钝头细长旋成体非对称流动的影响

Strake Sweep Angle Effects on the Asymmetric Flow over a Blunt Slender Body

为探究大迎角时边条翼前缘后掠角对钝头细长旋成体导弹绕流特性的影响,开展了模型表面测压和粒子图像测速的风洞实验,研究了亚临界Reynolds数Re=150000、迎角α=50°条件下不同前缘后掠角固定边条翼的钝头细长旋成体非对称绕流特性.结果表明,在边条翼上游区,后掠角增大使边条涡涡位更靠近前体物面且对称性更好,导致前体物面的压力分布更对称,截面侧向力减小;在边条翼区,后掠角增大加强了边条涡对前体非对称涡系的诱导作用;在边条翼下游区,后掠角增大减弱了边条涡对旋成体非对称涡系的诱导作用,加剧了旋成体物面的压力分布不对称性,导致截面侧向力变大.

Wind tunnel experiments were conducted to investigate strake sweep angle effects on the flow over a slender body at subcritical Reynolds number Re=150000 andα=50°.The slender body model has an optional device named strakes installed on the model.The sweep angle of the strake leading edges can be varied.Pressure measurements and particle image velocimetry were performed to study how the leading edge sweep angle of the strakes influence the pressure distribution and the wake over the model.The results show that,the strake vortices locate at a shorter distance to the model surface in front of the strakes and the vortices are symmetric about the model′s longitudinal center plane.It would symmetrize the wake over the model′s forebody and reduce the corresponding sectional side force.The strakes with larger sweep angle raise this tendency.The strake vortices couple with the asymmetric vortices from the forebody and gradually become asymmetric at the strake rear.At the downstream of the strakes,the induction effect of the strake vortices weakens as the sweep angle increases.It would result in the asymmetry of the pressure distribution on the body surface,which produces larger local side force.