水平轴风力机的设计与流场特性数值预测

Design and numerical prediction of flow field characteristics of horizontal-axis wind turbine

选用NACA44XX系列翼型,用基于叶素-动量理论的威尔森(Wilson)方法设计一模型风轮.考虑塔架机舱对流场特性的影响,合理地建立整机流动模型.在FLUENT软件中采用大涡模拟方法对该定桨距型的风力机进行三维绕流场的数值预测,得到流动细节与变形的螺旋形尾涡系.分析定桨距风力机的工作特点,并对尾涡变形原因做定性分析.结果表明:粘性耗散与塔架效应是引起尾涡变形的主要原因.

Selecting NACA44XX series aerofoils, the model of wind rotor was designed by using Wilson method based on blade element momentum theory. The affect of tower and nacelle was considered and the flow model was reasonably established and the numerical prediction of its 3D turbulent flow past fixedpitch wind turbine was made based on large eddy simulation in software FLUENT. The flow detail and deformed spiral trailing vortexes were obtained. The operation characteristics of fixed-pitch wind turbine was analysed and the origin trailing vortex distortion was qualitaively analysed, also. The result shows that viscidity dissipation and tower effect are main reasons of wake eddy distortion.