兆瓦级风机主轴轴承接触应力与疲劳寿命分析

发布时间：2018-04-25 19:42

本文选题：风机 + 主轴轴承　；参考：《太原理工大学》2017年硕士论文

【摘要】：风电行业的快速发展促进了风电专用轴承行业的发展,近年来我国在风电专用轴承的设计与制造上已经取得了很大进步。但是,在风电轴承的寿命、承载能力以及可靠性等方面,与世界先进水平还存在很大差距。风机主轴轴承是一种风电专用轴承,目前国内对风机主轴轴承接触应力与疲劳寿命的研究还不够深入。本文以某兆瓦级风力发电机主轴轴承为研究对象,对该轴承进行接触应力与疲劳寿命研究,分析影响轴承接触应力与疲劳寿命的因素,探究提高主轴轴承承载能力与疲劳寿命的方法,为风机主轴轴承的设计与制造提供一定的参考。论文的主要研究内容如下:1)在合理简化风机模型的基础上,分析载荷作用下主轴轴承的力学特性,计算出主轴轴承在额定风速下的受力,其中轴承所受径向力为653660N、轴向力为33643N。载荷计算结果可为后续轴承接触应力与疲劳寿命的研究提供依据。2)基于ANSYS有限元分析平台对建立的主轴轴承静力学模型进行接触应力分析,求解出轴承内外圈滚道在额定风速下的应力分布情况,确定出最下端滚子与轴承内圈接触处为轴承的危险受载位置。进一步分析了游隙、接触角对轴承接触应力的影响,得出了适当的负游隙以及较小的接触角可以提高主轴轴承承载能力的结论,可根据此对主轴轴承进行结构优化。3)基于Fe-safe疲劳寿命软件对主轴轴承在额定风速下的疲劳寿命进行计算,寿命结果满足风机20年额定设计寿命的要求。为了使主轴轴承能够在更为恶劣的工况下满足使用寿命的要求,进一步探讨了轴承表面粗糙度以及轴承制造残余压应力对其寿命的影响,计算出主轴轴承在不同表面粗糙度与不同残余压应力下的疲劳寿命。研究结果表明,提高主轴轴承表面粗糙度质量以及在轴承内外圈滚道表层引入有利的残余压应力,都可以极大程度地提高主轴轴承的疲劳寿命。本文的研究内容可为风机主轴轴承的设计与制造提供适当的参考,并对提高主轴轴承性能以及整个风机的发电效率有一定的指导意义。
[Abstract]:The rapid development of wind power industry has promoted the development of wind power special bearing industry. In recent years, great progress has been made in the design and manufacture of wind power special bearings in China. However, the bearing life, bearing capacity and reliability of wind power bearings are still far from the advanced level in the world. Fan spindle bearing is a special bearing for wind power. At present, the research on contact stress and fatigue life of fan spindle bearing is not deep enough. In this paper, the contact stress and fatigue life of a main shaft bearing of a megawatt wind turbine are studied, and the factors influencing the contact stress and fatigue life of the bearing are analyzed. The method of improving bearing capacity and fatigue life of spindle bearing is explored to provide some reference for the design and manufacture of fan spindle bearing. The main contents of this paper are as follows: (1) on the basis of reasonably simplifying the fan model, the mechanical properties of spindle bearing under load are analyzed, and the force of spindle bearing under rated wind speed is calculated, in which the radial force and axial force are 653660N and 33643N respectively. The results of load calculation can provide the basis for the study of contact stress and fatigue life of subsequent bearing. 2) based on ANSYS finite element analysis platform, the contact stress analysis of the static model of spindle bearing is carried out. The stress distribution of the inner and outer ring raceway of the bearing under the rated wind speed is solved, and the dangerous loading position of the bearing is determined at the contact point between the bottom roller and the inner ring of the bearing. The influence of clearance and contact angle on bearing contact stress is further analyzed. It is concluded that proper negative clearance and small contact angle can improve bearing capacity of spindle bearing. Based on this, the fatigue life of spindle bearing under rated wind speed can be calculated based on Fe-safe fatigue life software, and the life result can meet the requirement of 20 years' rated design life of fan. In order to satisfy the service life requirement of spindle bearing under worse working conditions, the influence of bearing surface roughness and residual compressive stress on its service life is further discussed. The fatigue life of spindle bearing under different surface roughness and different residual compressive stress is calculated. The results show that the fatigue life of spindle bearings can be greatly improved by improving the surface roughness of spindle bearings and introducing favorable residual compressive stresses on the surface of the inner and outer ring raceways of bearings. The research content of this paper can provide an appropriate reference for the design and manufacture of the main shaft bearing of the fan, and has certain guiding significance to improve the performance of the spindle bearing and the power generation efficiency of the whole fan.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH133.3;TM315

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