【作者】 张斌；

【导师】 王海军；

【作者基本信息】 沈阳工业大学 ， 固体力学， 2008， 硕士

【摘要】 本文以某风力发电机塔架作为研究对象,以ANSYS作为分析平台,对风荷载及地震波载荷作用下的结构动力响应进行了研究。本文尝试利用ANSYS中的CFD模块进行风场的建模与计算分析,并将流场计算结果同塔架结构成功耦合,对三种极限工况下的风力发电机塔架的抗风特性进行了分析。结果表明,当考虑风荷载同结构的耦合作用时,塔架的横风向位移变化较小,而顺风向位移则有较大幅度的增加;塔筒上的应力极值有一定程度的增加,增加的幅度需要视具体的工况来定。对塔架进行抗震动力响应特性分析时,对土与结构之间的相互作用分别采用基础完全固接法、土弹簧模拟法、以及截取部分地基土同结构建立整体有限元模型三种方法,通过输入EI Centro双向水平地震波,对塔架在地震波作用下的动力响应进行分析比较。相较于刚性地基假定,利用弹簧单元模拟土与结构之间的相互作用时,沿塔架高度方向水平位移、速度以及加速度的幅值均有不同程度的增加,并且速度及加速度时程的变化频率更快。截取部分土体与塔架一起建立整体有限元模型时,位移响应幅值略大于以土弹簧模拟SSI效应时的相应值,而速度响应幅值却小于后者,随着高度的降低,这种现象更加明显。通过对塔架结构时程响应的比较分析,本文对三种分析方法进行了初步的探索和研究,本文的研究结果为风力发电机塔架的设计与分析提供了一种参考。更多还原

【Abstract】 In this paper, the dynamic response of wind turbine tower under seismic and wind load is analyzed by using of ANSYS software. This thesis tries to model and analyze the wind field and realize the coupling between the flow field’s result and tower structure’s result. The characteristics of wind resistance in three limited cases are analyzed. The results show that, when the coupling of wind load and structure is considered the downwind displacement of the tower can be much effected, and the maximum Von-Mises stress on the tower will become larger, but the incensement should be determined by considering different limited loads. This analysis method overcomes a large number of empirical formula and assumptions which are used in the traditional method of analysis, realizing the coupling between the wind and the structure successfully.In addition, this paper establishes the element model of the tower by using three different kinds of theory, realizing the calculation and analysis of the tower structure under the seismic load. Through comparison and analysis, some useful conclusions are obtained: In order to simulate the dynamic response, interaction of the soil-structure system must be considered. This paper simulate the interaction between soil and basis structure by using soil spring, then the data solved by using this method are compared with the results which the interaction between soil and basis structure are not considered. The results show that dynamic interaction of the soil-structure system influents dynamic characteristics of the wind turbine tower structure and increases displacements, speeds and accelerations of the structure. In addition, this paper establishes the overall finite element model considering both the foundation and the wind turbine tower structure. The results show that the extreme value of the displacement is larger than the counterpart using soil spring a little, but the extreme value of the velocity is smaller than the latter. This trend is more obvious in relatively lower position. A preliminary exploration and research by using three methods of analysis is conducted in this paper.The results which are obtained in this paper can provide a reference for design and analysis of the wind turbine tower.更多还原