With the previous knowledge of the effectiveness of single-split blades, questions arise about the effectiveness of a double-split configuration on horizontal axis wind turbine. To shed light on this question, a 3-D double-split finite-span configuration with S809 airfoil profile is designed based on the results of unsteady DES simulations of two families of single-split configurations. Firstly, the two 3-D single-split families with four different values of split width are simulated at angles of attack (AOA) up to 25°. Secondly, a finite span double-split model is designed based on the single-split geometries with the highest aerodynamic performances. It has been found that the double-split configuration had the poorest performance for 0°<AOA<17°; however, at 17°<AOA<22°, the double-split model showed the highest performance. Analyzing the time-averaged streamlines showed that excessive injected flow at low AOAs as well as the formation of separation bubbles inside the split channel were two main negative factors that severely reduced the performance of the double-split geometry. Also, findings revealed that using optimum cases of single-split geometry does not result in an optimum double-split geometry. Lastly, considering all findings, a conceptual selective (controlled) flow control method that led to a considerable increase in the aerodynamic performance of the double-split geometry has been proposed and discussed.

有了对单裂式叶片的有效性的先前知识，人们就对水平轴风力涡轮机上的双裂式配置的有效性提出了疑问。为了阐明这个问题，基于两个单分裂配置系列的非稳态DES仿真结果，设计了具有S809翼型轮廓的3-D双分裂有限跨度配置。首先，以高达25°的迎角（AOA）模拟具有四个不同分割宽度值的两个3-D单分割族。其次，基于单缝几何结构设计了有限跨度的双缝模型，具有最高的空气动力学性能。已经发现，对于0°＜AOA ＜17°，双分裂配置具有最差的性能。但是，在17°<AOA <22°时，双分裂模型表现出最高的性能。分析时间平均流线表明，在低AOA时过多的注入流量以及在分流通道内形成分离气泡是严重降低双分流几何性能的两个主要负面因素。而且，研究结果表明，使用单分割几何的最佳情况不会导致最佳双分割几何。最后，考虑到所有发现，提出并讨论了一种概念上的选择性（受控）流量控制方法，该方法导致了双分流几何结构的空气动力学性能的显着提高。研究结果表明，使用单分割几何的最佳情况不会导致最佳双分割几何。最后，考虑到所有发现，提出并讨论了一种概念上的选择性（受控）流量控制方法，该方法导致了双分流几何结构的空气动力学性能的显着提高。研究结果表明，使用单分割几何的最佳情况不会导致最佳双分割几何。最后，考虑到所有发现，提出并讨论了一种概念上的选择性（受控）流量控制方法，该方法导致了双分流几何结构的空气动力学性能的显着提高。