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1、 2017 届毕业设计（论文）题 目；风力机塔架疲劳寿命分析专 业： 机械工程班 级： 机械1307姓 名： 赵向杰指导老师： 杨谋存起讫日期：2017.6摘要3第一章 概述771.1.1 风电行业发展现状71.1.2 风力机简介81.1.3 风力机塔架简介91.2 风力机塔架疲劳寿命分析的意义101.3 国内外研究现状111.3.1 国外研究风力机塔架的现状11国内研究风力机塔架的现状121.4 本论文所做的工作12第二章 风力发电机组结构及其分析理论132.1 风力发电机组的结构及其关键部件132.2 有限单元法理论142.2.1 有限元法简介142.2.2 有限元的基本理论182.3 有
2、限元分析软件 ANSYS182.3.1 ANSYS 软件的基本组成、功能18第三章 风力机塔架的静应力分析20引言202.2 水平轴风力机机理202121223.3 塔架的有限元建模233-3-4 底座的网格划分263.4 应力计算及snsys模拟分析273.5 本章小结33第四章 风力机塔架的疲劳分析评价354.1 疲劳分析的基本理论354.1.1 结构的疲劳定义354.1.2 影响结构疲劳的主要因素354.1.3 结构疲劳的研究方法364.2 塔架的疲劳ANSYS分析基本原理374.3 ANSYS疲劳模拟分析404.4 本章小结41第五章 结论与展望42参考文献44致谢46摘要新生能源正在
3、逐渐崛起，也正慢慢的影响着我们的日常生活。其中最为瞩目和令人称道的便是风能。风能现如今被认为是最具开发潜能和实效作用的清洁能源，其所能利用的价值不可估量。风能，顾名思义，最主要的能源来源取自风力，通过一系列运作，达到风力发电的效果。当然，风力发电也并非易事，基本需要诸多繁琐的流程，才能达到理想的效果。它的塔架需要经受多种载荷，并且因为剪切风、阵风等缘故会导致振动，从而造成风力发电机组的损坏。因而，对风力机塔架实行动静态的特质分析有着不一般的意义。也未解决后期风力发电可能会面临的问题做足思考和准备，以备不时之需。 本文在思考某定型风力发电机组塔架结构特性和受力特质的基础上，设立了变截面筒型塔架的
4、力学结构模型。在结构动力学原理上，推理出了塔架顶尖水平位移、基频的计算公式和在综合考虑叶轮、机舱及塔架自重共同影响下的临界力计算公式;分析了塔架的固定参数及载荷对整机的稳固性和疲劳特质的影响作用。并运用有限元法和ANSYS 软件对塔架实行动静态特性的模拟数值分析。主要内容和结论如下： 1.运用有限元数值模拟的结果与运用概念计算得出的结果十分相识，考证了有限元模拟的准确性。塔架底端开门洞和在不同的风速下变桨角导致了塔架上边各部件要点的改变对塔架静强度产生了轻微的作用。因而，我们在对风力机塔架实行力学分析和设计计算时应该从实际情况分析思虑。 2.对塔架实行振动特质和响应分析，在对几类差别模型的数值
5、进行模拟分析，得出塔架底部机头的品质和底部根基的强度对塔架的固定频率有一定的影响。通过对动态的响应分析，能够得出塔架在不同的频率下的回应，峰值和频率所相对结构的变形和合力；并且通过计算得出塔架在各时间的位移、速度和加速度，进而为对风力机的优化设计务实了根基。 3.对塔架实行收缩统计，充分利用 ANSYS 数值模拟分析，同期在塔筒接连处，运用实体单元对法兰盘模拟结果进行计算有很高的精确性，可以实现一般工程的运用，而且比现今工程计算更加的安全。相对于底层开门洞的塔架，门洞处区域可能会引起收缩失衡。薄壁圆柱壳是相对缺陷敏感的结构部分，需要考虑到门洞对收缩的作用，同期运用门框强化结构，可能会增加塔架的
6、收缩印度。 4. 对塔架实行疲劳统计，能够得到塔架的疲劳寿命基数，测验风力机塔架的应用寿命状况，校正核塔架的疲劳使用强度。 关键词：风力机塔架；有限元；振动特性；屈曲；疲劳寿命 Abstract Wind energy is currently the most promising development and utilization of a renewable energy. One of the main ways of wind energy utilization is wind power generation. However, the working environment
7、of wind turbine system is very complicated, and its tower is subjected to various loads, and shear wind, gust and so on cause vibration, which leads to the destruction of wind turbine. Therefore, it is of great significance to analyze the static and dynamic characteristics of the wind turbine tower.
8、 In this paper, the mechanical model of variable cross - section cylindrical tower is established by combining the structural characteristics and the characteristics of the tower of a certain type of wind turbine. Based on the structural dynamics principle, the calculation formula of horizontal disp
9、lacement and fundamental frequency of tower top and the calculation formula of critical force under the combined action of impeller, engine room and tower weight are deduced. The specific parameters and load of tower are studied. Stability and fatigue properties. And the finite element method and AN
10、SYS software were used to simulate the static and dynamic characteristics of the tower. The main contents and conclusions are as follows: 1. The finite element numerical simulation is close to the theoretical calculation, and the correctness of the finite element model is verified. The opening of th
11、e tower at the bottom of the tower and the pitch at different wind speeds cause the change in the center of gravity of the components above the tower to have a certain influence on the static strength of the tower. Therefore, in the wind turbine tower for mechanical analysis and design calculations
12、should be considered according to the actual situation. 2. The vibration characteristics and response analysis of the tower are analyzed. Through the numerical simulation of several different models, the quality of the bottom of the tower and the stiffness of the bottom foundation have a great influ
13、ence on the natural frequency of the tower. Through the dynamic response analysis, the response of the tower at different frequencies and the deformation and stress of the corresponding structure of the peak frequency can be obtained. At the same time, the displacement, velocity and acceleration of
14、the tower are calculated at the same time, so as to lay the foundation for the optimization design of the wind turbine The foundation. 3. The buckling analysis of the tower, the use of ANSYS numerical simulation, at the same time in the tower connection, the use of solid elements on the flange simul
15、ation results have a high accuracy, to achieve the general application of engineering, and than the current engineering calculations Biased towards safety. For the bottom of the tower to open the door, near the hole may occur buckling instability. Thin-walled cylindrical shells are defect-sensitive structures that take into account the effect of the door on the buckling, while the use of the door frame to strengthen the structure will increase the buckling strength of the tower. 4. Fatigue analysis of the tower, you can get the fa
