基于动网格方法的拍动平板升力分析

Lift performance analysis of flapping flat plate using dynamic mesh method

针对微型飞行器,采用动网格方法计算了旋转超前、同步、滞后3种拍动模式下的平板升力性能.通过比较分析二维、三维拍动平板的升力性能以及尾涡分布变化,探讨了拍动平板升力性能与其运动规律的关系.计算表明:旋转同步和超前模式下的平板升力系数明显高于旋转滞后模式下的平板升力系数;二维、三维平板升力系数均随角振幅的增大而减小,随相位差的增大而增大,拍动振幅的影响相对较小;角振幅较大时,旋转超前模式中三维平板升力系数均明显高于二维平板升力系数,旋转同步模式中二维、三维平板升力系数变化不明显,旋转滞后模式中仅当小角振幅且小平移振幅时,三维平板升力系数增加较大.

Aim at micro air vehicles,two-dimensional and three-dimensional flapping flat plate lift performance of advanced,synchronized and delayed rotation were numerically investigated by dynamic mesh method.The vortices and lift changes versus kinematic motions were highlighted to analyze the relationship between lift performance and kinematic motions.Numerical results show that the lift coefficients of synchronized and advanced rotation model are larger than that of delayed rotation obviously;the lift coefficients of two-dimensional and three-dimensional flapping plate decrease with increasing of angular amplitude and increase with increasing phase lag,while the influence of plunging amplitude is less relatively.The lift coefficients of three-dimensional plate are larger than two-dimensional plate in advanced rotation model with higher angular amplitude,also in delayed rotation only when lower angular amplitude and shorter plunging amplitude.The lift coefficients of two-dimensional and three-dimensional flapping plate are not changed significantly in synchronized rotation with higher angular amplitude.