论文部分内容阅读
透平机械动叶振动的分析方法早已问世。该法以薄壳理论为基础,用里兹(Ritz)法计算频率和振型。但迄今为止,该法仅适用于等厚度、等曲率叶片或扭曲的、平面图形为矩形的叶片。本文将阐明该法如何突破上述限制条件,对非矩形的平面图形通过一适当的坐标变换处理,变厚度、变曲率和扭曲需用数值积分。本法通过四例悬臂片叶得以论证,其理论数据和实验数据早已发表:(1)叶高方向有锥度的平板;(2) 叶弦方向有锥度的平板;(3)叶弦方向有锥度的扭曲板;(4)叶弦方向有锥度的柱面壳体。
Turbine blade analysis of mechanical vibration has long been available. The law based on the thin shell theory, using the Ritz method to calculate the frequency and mode shapes. But so far, this method is only applicable to equal thickness, constant curvature leaves or twisted, rectangular leaves. This article will clarify how the law breaks through the above restrictions. For non-rectangular planar graphics, through appropriate coordinate transformation, numerical integration is needed for variable thickness, curvature and distortion. This method is demonstrated by four cases of cantilever leaves, the theoretical data and experimental data have been published: (1) the plate with a taper in the leaf height direction; (2) the plate with taper in the leaf chord direction; (3) Of the twisted plate; (4) leaf chord direction taper cylindrical shell.