摘 要

现代工业的发展，各种机械设备飞速，汽轮机也发展的十分迅速，效率和各方面性能都有了很大的提高。特定场合下，汽轮机的振动和噪声的要求很高。转子的运行过程中存在疲劳破坏，于是在转子在运行和提高寿命方面有一定的改进空间。将磁悬浮技术运用汽轮机转子系统，磁力轴承代替机械轴承，可降低转子与轴承的摩擦力与力矩，提高效率，降低维护费用，有利于汽轮机在更多的领域得到应用。将磁悬浮技术应用在汽轮机中具有重大意义和实用价值。

本文主要对汽轮机进行研究，了解了汽轮机基本原理后，结合国内外汽轮机发展前沿水平，针对转子工作结构完成建模，利用建得三维模型对汽轮机进行分析和研究。

利用SolidWorks建立汽轮机转子模型，并用有限元分析软件ANSYS对所建模型进行了模态分析，提取了转子的前14阶固有频率，确定了转子系统的临界转速。

设计了汽轮机的整体结构，主要考虑了转子和静子系统的安装组合，形成最终的汽轮机结构。

关键词：汽轮机；磁悬浮技术；磁悬浮轴承；有限元分析

Abstract

The development of modern industry, all kinds of mechanical equipment, the rapid development of the turbine is very rapid, efficiency and performance in all aspects have been greatly improved. In particular, the vibration and noise of the steam turbine are very high, and there is a certain improvement of the rotor during the operation of the rotor, which has a certain improvement in the operation of the rotor and the improvement of the life.Use of steam turbine rotor system of the magnetic levitation technology, magnetic bearing to replace a mechanical bearing, reduce friction and torque of the rotor and bearing, improve efficiency, reduce maintenance costs, is conducive to the steam turbine has been applied in more fields.It is of great significance and practical value to apply the magnetic levitation technology to the steam turbine.

In this paper, the research status and development trend of the research progress at home and abroad are summarized, and the general structure and working principle of the turbine are simply introduced.On this basis, according to the actual structure of the rotor, the corresponding equivalent simplification is carried out, and the overall analysis and design of the turbine is carried out, and the model of the mechanical structure of the turbine rotor is established.

The turbine rotor model was established by SolidWorks, and the modal analysis of the model was carried out by using the finite element analysis software ANSYS. The first 14 order natural frequencies of the rotor were extracted, and the critical speed of the rotor system was determined.

The design of the overall structure of the steam turbine, the main consideration of the installation and combination of rotor and stator system, the formation of steam turbine structure in the end.

Key Words： steam turbine; magnetic levitation technology; magnetic bearing; finite element analysis

目录

第1章 绪论…………………………………………………………………………….1

1.1课题研究背景……………………………………………………………………...1

1.2磁悬浮转子概述……………………………………………………………………3

1.2.1磁悬浮工作原理……………………………………………………………….4

1.2.2磁悬浮特点及应用…………………………………………………………….6

1.3研究现状和目前问题………………………………………………………………7

1.4研究主要内容………………………………………………………………………8

第2章 磁悬浮汽轮机转子的分析与设计…………………………………………….26

2.1汽轮机组成与工作原理…………………………………………………………..26

2.1.1小型汽轮机……………………………………………………………………………..27

2.2传统汽轮机转子…………………………………………………………………..29

2.3磁悬浮汽轮机转子………………………………………………………………..30

第3章 汽轮机整体设计………………………………………………………………31

3.1汽轮机转子设计…………………………………………………………………..32

3.2磁悬浮轴承设计…………………………………………………………………..33

3.2.1径向磁悬浮轴承设计………………………………………………………...34

3.2.2轴向磁悬浮轴承设计………………………………………………………...35

3.3汽轮机整体………………………………………………………………………..36

第4章 汽轮机转子模态分析………………………………………………………….35

4.1 模态分析的实现………………………………………………………………...36

4.1.1有限元参数设置……………………………………………………………...37

4.1.2求解………………………………………………………………………… ..38

4.2 模态分析结构及评价…………………………………………………………...39

4.2.1振型分析……………………………………………………………………...40

4.3 转子动态特性分析……………………………………………………………...41

第5章 总结与展望……………………………………………………………………42

5.1总结………………………………………………………………………………42

5.2展望………………………………………………………………………………42

参考文献…………………………………………………........................................50

致谢………………………………………………………………………………….51

第1章 绪论

• 1. 课题研究的目的和意义

随着现代工业的迅速发展，各种高速旋转机械，如各种类型的汽轮机设备迅速发展起来。国民经济如电力，石油，化工，航空冶金等重要领域，都有诸多旋转机械在发挥着重要角色，如大型汽轮机组，压缩机，风机等。汽轮机可用于发电，也可用作驱动机械，因此广泛应用于发电站，大型轮船等设备，另外汽轮机使用过程中未完全利用的热量还可以拿来供热。汽轮机的蒸汽通流过程流量大效率高可达到更高的功率。大功率汽轮机可以采用较高的蒸汽压力和温度，故热效率比较高。一直以来汽轮机不断发展，越来越安全，越来越可靠，功率越来越大，效率越来越高。其中汽轮机轴承是最为关键的一环，在大多数情况下，轴承对于转子的动力特性有很明显的影响。轴承往往是阻尼的主要来源，因而控制着转子的响应；轴承的刚度和阻尼又影响着转子的临界转速和稳定性。我国电力系统发展很大程度上依靠汽轮发电机，并且随着技术的发展，发电量和转速都得到了提高，于是汽轮机在运转中容易出现的问题如振动等就成了急需解决的难题，轻则噪声效率低重则引发安全问题。振动问题尤为复杂。

• 1. 磁悬浮转子概述

磁悬浮转子是利用磁力轴承作为支承的转子系统,将被支承件利用电磁力稳定悬浮在空间,使支承件与被支承件隔绝的一种高性能机电一体化轴承。磁悬浮轴承是一种新型高性能轴承，具体优点如下：