基于ANSYS的矩形烟风道有限元分析

发布时间：2018-08-28 17:14

【摘要】：烟风道是电站锅炉烟风系统中的主要部件,在锅炉运行过程中,烟风道起着运输空气或者烟气的重要作用。锅炉运行过程中,烟风道需要承受自重、保温重量、介质压力、积灰重量、风载荷等各种载荷,而烟风道墙板为薄板结构,强度较弱,难以承受各种载荷的单独及共同作用,因此,合理选择烟风道墙板厚度及加强筋规格对烟风道结构设计及成本控制至关重要。本文首先介绍了烟风道墙板设计现行方法的理论知识,如薄板大挠度弯曲问题、加强筋弯曲和振动问题的求解方法,以及工程上烟风道道体设计的方法。然后对烟风道有限元法计算的相关有限元理论知识进行了介绍,根据某工程的烟风道设计图,利用三维造型软件Pro/E建立了矩形烟道、热风道和冷风道的实体模型,将实体模型导入ANSYS后建立烟风道的有限元模型,给出各部件的材料力学性能参数,并给出了各段模型在工作运行中可能受到的载荷以及其边界条件等。针对烟风道的强度、振动和稳定性的控制条件,对烟风道进行了静力、模态和屈曲分析。根据这些分析,烟风道能够满足强度和刚度条件,振动频率也符合设计规范。在上述分析的基础上,对转弯烟道进行了优化设计,得到了各设计变量与烟道墙板应力和槽钢形变之间的关系,得出了各设计变量对目标函数的影响程度,能够有效的针对烟道进行优化设计。通过对500个设计点的计算,得出转弯烟道最佳的设计点,比初始设计点下转弯烟道的重量减轻了13%,有效的降低了烟道的制造成本。本文基于工程实际情况,对某工程的烟风道进行了有限元分析计算和优化分析,为烟风道的设计提供了参考,具有工程实际意义。
[Abstract]:Flue gas duct is the main component of boiler flue gas system in power plant. In the process of boiler operation, flue gas duct plays an important role in transporting air or flue gas. During the operation of the boiler, the smoke duct needs to bear all kinds of loads such as weight, heat preservation weight, medium pressure, ash accumulation weight, wind load and so on, while the wall board of the flue duct is a thin plate structure, so the strength of the wall board is weak, so it is difficult to bear the single and common action of all kinds of loads. Therefore, it is very important to select the thickness of wall board and strengthen the reinforcement specification for the structure design and cost control of flue duct. This paper first introduces the theoretical knowledge of the existing methods for the design of smoke duct wall panels, such as the problem of large deflection bending of thin plates, the method of solving the bending and vibration problems of stiffeners, and the method of design of flue ducts in engineering. Then, the relevant theory of finite element method is introduced. According to the design diagram of a project, the solid models of rectangular flue, hot air duct and cold air duct are established by using 3D modeling software Pro/E. The finite element model of the flue is established by introducing the solid model into ANSYS, and the mechanical properties of each component are given, and the load and boundary conditions of the model are given. The static, modal and buckling analysis of the flue is carried out according to the control conditions of the strength, vibration and stability of the flue. According to these analyses, the smoke duct can satisfy the condition of strength and stiffness, and the vibration frequency also accords with the design code. On the basis of the above analysis, the optimum design of the turning flue is carried out, and the relationship between the design variables and the stress of the wall plate of the flue and the deformation of channel steel is obtained, and the influence of each design variable on the objective function is obtained. Can effectively carry on the optimization design for the flue. Through the calculation of 500 design points, the optimum design point of turning flue is obtained, which reduces the weight of turn flue by 13% compared with the initial design point, and effectively reduces the manufacturing cost of flue. Based on the actual situation of the project, the finite element analysis and optimization analysis of the flue duct of a certain project are carried out in this paper, which provides a reference for the design of the flue duct and has practical significance in engineering.
【学位授予单位】：上海交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM621.2

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