攻角对螺旋桨非定常特性的影响分析

为了分析入流速度攻角的连续变化对螺旋桨非定常特性的影响,应用滑移网格技术对螺旋桨运动进行了数值分析。结果表明:螺旋桨的时均拉力会随攻角的增大而增加;对于各单独叶片而言,向下运动时,随着攻角的增大,拉力会逐渐增加,向上运动时,拉力则会减小;在特定方位角时,随着攻角的增大,桨叶前端的轴向速度会略微增大,桨叶后端的轴向速度在小攻角时也会发生略微的变化,但在攻角较大时变化较明显;随着攻角的增大,桨叶所受到的周期性非定常载荷的波动会逐渐加剧。

Effect of Attack Angle on Propeller Unsteady Characteristics

In order to analyze propeller unsteady characteristics induced by attack angle, sliding mesh method is utilized to simulate propeller moving. The results show that time-averaged thrust of propeller grows with the increase of attack angle. For isolated blades, when blade moves down, thrust is increased gradually with the increase of attack angle, and when blade moves up, it is reduced gradually. At a special angle, axial velocity of the front of propeller increases slightly, and axial velocity of the propeller back also increases slightly when attack angle is small, but it changes obviously when attack angle is large. The periodic unsteady load of blade is exacerbated at attack angle.