叶轮机超音速非失速颤振边界研究

把叶片简化为具有对称截面、长、直、带预扭的非均匀弹性梁 ,并结合超音速状态下计算由振动引起的非定常气动载荷的气动模型 ,用哈密尔顿原理建立一组旋转状态下失调叶栅气弹稳定性方程 ;这组方程对弯曲—弯曲—扭转之间耦合严重的失调叶栅尤有意义。对一个风扇级进行的气弹稳定性分析结果表明 :失调及其幅度、阶次 ,扭心位置 ,耦合效应及其程度对叶栅气弹稳定性有明显的影响

SUPERSONIC UNSTALLED FLUTTER IN ARBITRARY MISTUNED CASCADES

By the use of Hamilton's principle,a set of aeroelastic equations is formulated to describe the motion of an arbitrary mistuned rotating cascade with high aspect ratio,flexible pretwisted,nonuniformed blades.A two dimensional aerodynamic theory is used to calculate unsteady force and moment coefficients for vibrating aerofoil in supersonic unstalled cascade.This set of equations is of great value to a fan blade with the inertial,structural and aerodynamic coupling in bending bending torsion.Results obtained from the aeroelastic stability analysis of a real fan stage show that amplitude and different order of mistuning and other kinds of structural properties have an apparent effect on boundaries of supersonic unstalled flutter.