垂直轴风机的结构受力分析及其优化

Mechanical Analysis and Optimization of Structures in Vertical Wind Turbine

风力发电机的应力分析是保障其安全运行乃至结构设计的基础.垂直轴风机的支撑结构一般都是超静定的,主要承受风载及高速旋转引起的离心力,因此对风轮重量有严格的要求.在结构总体设计时必须先对其进行力学分析,并进行受力优化,才能进行详细的零部件设计,数值分析往往只在设计基本定型后才能进行.一些风机在大风时发生飞车事故,其原因都是因为结构受力不合理导致关键部位应力过大或强度不足所引发的.本文针对垂直轴风机叶片和支撑系统,首先对支点位置进行优化,并推导出叶片、支撑杆、斜拉索等的受力公式,为此类部件的设计提供广适性的力学方法,并对垂直轴风机的一些关键安全性问题进行讨论.

Stress analysis is especially important to insure wind turbine＇s safety and to design the structure reasonably. Structures in vertical wind turbine are commonly statically indeterminate, and are mainly subjected to wind loading and centrifugal force induced by rapid rotating. Therefore, there is a strict weight limit requirement on wind turbine. Before the detailed design of structures, loading acted at each component must be analyzed at first, systematical numerical analysis can be carried out only after the structure design having been fixed. From the view of stress, failure of wind turbine is usually caused by non-reasonable design. However, loading at components is dependent on the structure＇s style such as supporting position, additional constriction, etc. Therefore, mechanical analysis plays an important role in the optimization of structure. This paper has analyzed the forces in typical vertical wind turbine, and deduced the force expressions for the main components. Some important problems related to the structure＇s safety have been also discussed.