燃气轮机带冠叶片耦合振动分析

带冠叶片不但能调频，还可以利用叶冠之间的摩擦效应来耗散能量，达到减振的目的。带冠叶片在离心力场中形成一整体，其整圈叶片振动特性不同于单个弧立叶片，需考虑叶冠的整体效应。利用带冠叶片系统的循环对称性，提出了采用波传播理论和模态综合技术，结合有限元方法研究燃气轮机带冠叶片振动特性的分析模型和计算方法。算例和工程应用证明了该方法是有效的、正确的，并可以大大降低计算分析规模。研究表明带冠叶片动力特性分析时必须考虑整圈叶片的耦合效应。

Coupled vibrations of gas turbine shrouded blades

Presents the model proposed for analyzing the vibration characteristics of shrouded blades and their calculation method by employing a wave propagation theory and modal synthesis technology coupled with a finite element method from the view point it is possible not only to conduct frequency modulation of the shrouded blades of a gas turbine, but also to utilize the friction effects between them to dissipate energy, thereby attaining the aim of vibration alleviation, as shrouded blades have been widely used in the design of high-speed turbomachinery, such as modern gas turbines and steam turbines, and with the shrouded blades forming an integral whole in a centrifugal force field, the vibration characteristics of the whole ring of blades are different from those of a single isolated blade, and this makes it essential to take into account the integral effect of blade shrouds, Concludes from the calculation examples and engineering application that the above approach is valid and correct along with the possibility of considerably reducing the scale of calculation and analysis, and points out it is necessary to take into consideration the coupled effect of the whole ring of blades while the dynamic characteristics of shrouded blades is being analysed.