除尘器壳体纵梁承载性能的非线性分析

Nonlinear finite element analysis on bearing capacity of the vertical beam of large-scale electrical dust precipitator

大型电除尘器钢结构为空间杆系与壳体混合结构体系,杆件种类多,受力状态复杂。传统的设计方法不能明确结构体系的承载性能,需进一步分析其非线性承载性能,并优化结构体系和构件截面。运用有限元软件ANSYS,对某大型电厂300MW机组电除尘器壳体钢结构纵向大梁(仅有弯矩作用下及较大轴力、弯矩共同作用下)建立有限元模型,对整体结构进行静力分析、特征值屈曲分析及极限承载力分析。以分析结果为依据对仅有弯矩作用下的纵梁提出优化方案建议。计算结果表明,两类梁模型均满足设计荷载下的承载能力要求。

The steel structure of largescale electric dust precipitator applies the combination structural system of spatial bars and shells, which has various bar and complex bearing states. It is not appropriate for the traditional calculation method to precisely evaluate the bearing capacity of the structural system, so a further nonlinear analysis is needed, and the structural system and member section need to be optimized. A finite element model of the vertical beam （only under moment, under both larger axial force and moment） of steel shell structure is established for a large - scale electric dust precipitator with finite element software ANSYS. The static analysis of the integral structure, eigen buckling analysis and ultimate strength analysis are proceeded. Based on the results of the analysis, this paper proposes an optimized program for the vertical beam only under moment. The calculation results show that the two types of beam model are designed to meet the loading capacity requirements