汽轮机末级叶片颤振设计

随着汽轮机的大型化和多样化，汽轮机的叶片振动安全性会出现新的问题，叶片会在非共振强迫振动下产生振动疲劳破坏。研究表明．这是一种叶片颤振。目前，预估汽轮机叶片失速颤振的简化方法有：半经验法、经验法和三维粘性失速颤振数值解法。本文从微分方程稳定性原理出发，阐明了叶片颤振的机理。介绍了几种预估末级叶片颤振的方法，变形激盘法是作．者早期与北航共同开发的一种半经验法，已用于工厂叶片颤振设计。并根据作者的经验，推荐了几种经验法来预估叶片的颤振特性。

Flutter Design for Steam Turbine Last Blade

The blade vibration security appears a new problem along with the hugeness and diversification of steam turbine.The vibration fatigue breakage in the last blade can be engendered on non-resonance of force vibration.The research indicates it is a blade flutter.At present the simplified method for estimating stall flutter of steam turbine last blade flutter has half-experience method,experience method and three dimensional viscous flow numerical analysis stall flutter in steam turbine blades.This paper elucedates the blade flutter mechanism from stability principle of differential eguation.Also a few methods for estimating stall flutter of last blade is introduced.The"distortion disc method"is a half-experience method developed by the author and Beijing Aviation Institute.It is used in the blade flutter design.Some experience methods used to estimating stall flutter characteristic are suggested.