火电厂圆形烟风道模态分析与稳定性分析

Modal Analysis and Stability Analysis of Circular Flue Ducts in Thermal Power Plants

以某火力发电厂1000MW发电机组的圆形截面烟道为研究对象,对其中的除尘器前烟道、引风机前烟道和引风机后烟道三个主要结构均建立有限元模型,并以此展开模态分析和稳定性分析。分析结果显示,上述结构均具有较高的稳定性,仅在径向上的刚度有待于进一步提升,因此在后续的优化工作中,可通过增加加固肋的型号予以优化,以提高刚度,同时也有助于提高系统固有频率并降低共振风险。

Taking the circular cross-section flue of a 1,000 MW generating unit of a thermal power plant as the object of study,a finite element model is established for the three main structures of the flue in front of the dust collector,the flue in front of the induced draft fan,and the flue after the induced draft fan,and modal and stability analyses are carried out in this way.The results show that the above structures have high stability,and only the radial stiffness needs to be further improved,therefore,in the subsequent optimisation work,it can be optimised by increasing the type of reinforcement ribs to improve the stiffness,and also help to improve the intrinsic frequency of the system and reduce the risk of resonance.