风力机叶片的全局表面摩擦力测量的荧光油膜法

Fluorescence Oil Film Method for Global Skin Friction Measurement of Wind Turbine Blade

表面摩擦力是分析和预测风力机叶片气动特性的重要途径之一。为了实现风力机叶片全局表面摩擦力测量,获得流动在叶片上的拓扑结构,理解相关流动机理,引入了荧光油膜测量技术,给出了荧光油膜在表面摩擦力作用下的演化模型,并讨论了该演化模型的求解方法。为了验证该方法在风力机叶片上运用的可行性,设计了一个简化实验。实验中以平板代替具有三维弧面的叶片,并采用不同角度的倾斜射流冲击给定平板,以获得不同摩擦场。实验结果与E M Sparrow和B J Jovell给出的测试数据一致,这意味着基于荧光油膜的全局表面摩擦力测量方法具有测量风力机叶片上全局表面摩擦力的潜力。

The skin friction measurement is an important technique that analyses and forecasts the wind turbine blade aerodynamic characteristics.To measure the global skin friction and to obtain the flow topological structure on the surface of a wind turbine blade,a fluorescence oil film measurement is introduced.The evolution model of the fluorescence oil film is given,and the solution of the model is then discussed.A simplified experiment is designed to verify the feasibility of this method.In the experiment,the blade with three-dimensional surface is replaced by a flat one,and the inclined jet at different angles impacts on the flat blade to get different friction fields.The experimental results are in good agreement with the data measured by E M Sparrow B J Jovell.This demonstrates that the fluorescence oil film measurement is potential in the measurement of the global skin friction on wind turbine blades.