一种新型垂直轴风力机的CFD分析

Savonius风力机由于作用在叶片的凸面上的"负阻力"和来流不稳定性导致效率低,该"负阻力"造成一个负转矩降低了输出功率,并且在某些来流角度下导致原装的Savonius风力机启动困难。本文提出一种采用控制叶片数目和叶片不同弯曲度的控制来提高风能的利用率,并用CFD方法模拟不同转子结构的内流特征,为消除"负阻力",提出一种采用导叶或挡风板的结构实现引流,并数值分析了该结构的流动特征。模拟结果显示,新结构的多叶片Savonius风力机的转矩和启动特性有明显改善,且功率系数也比普通的Savonius风力机高。

CFD Study of a New Type of Vertical Axis Wind Turbine

The efficiency of the Savonius wind turbine is low because of its unstable torque and also due to the negative drag exerted on the convex part of the blades.That negative drag creates a negative torque lowering the efficiency.At some wind angles,the standard Savonius rotor can’t even start rotating.This study presents a way to improve efficiency by increasing the number of blades and by covering the convex part of the blades behind a shield or vane.Multi-bladed Savonius rotors have a more stable torque along the rotation and therefore present a better starting ability;their power coefficient can also be higher than the standard Savonius rotors if the right parameters are used.Design parameters such as blade number and dimensions have a strong influence on the aerodynamic efficiency.