Adaptive flap as a new flow control technique with adaptability to the changing flow separation has recently attracted much attention. This study uses the adaptive flap to mitigate the flow separation of a vertical axis wind turbine with a high solidity of 0.75 and investigate its performance and flow control mechanism by considering different flap lengths and locations. The fluid flow is simulated using computational fluid dynamics with the shear-stress transport k-ω model, and the flap motion is calculated based on the fluid–solid interaction methodology. The results show that the flap can be adaptively raised by the backflow caused by flow separation and used to block the backflow. The blocking of the backflow alleviates the flow separation problem and increases the blades’ aerodynamic torque. However, the long flap causes a negative effect due to its inability to retract timely when the flow tends to the attached state at high tip speed ratio scenario. It is observed that the short flap can avoid this problem when it is located far from the blade leading edge. Also, the short flap located closer to the blade leading edge performs better at low tip speed ratios, even though the performance is observed to be weakened by the trailing edge vortices suppressing the flap from deployment. This study provides a technical approach and theoretical basis for better alleviating the flow separation problems in vertical axis wind turbine.

自适应襟翼作为一种新的流量控制技术，能够适应不断变化的流量分离，近年来备受关注。本研究使用自适应襟翼来减轻高密实度为 0.75 的垂直轴风力发电机的流动分离，并通过考虑不同的襟翼长度和位置来研究其性能和流动控制机制。使用计算流体动力学模拟流体流动，剪切应力传递k-ω模型，襟翼运动是基于流固相互作用方法计算的。结果表明，挡板可以通过流动分离引起的回流自适应地升高并用于阻止回流。回流的阻塞减轻了流动分离问题并增加了叶片的气动扭矩。然而，在高叶尖速比情况下，当气流趋于附着状态时，长襟翼无法及时收回，因此会产生负面影响。据观察，当短襟翼远离叶片前缘时，它可以避免这个问题。此外，靠近叶片前缘的短襟翼在低叶尖速比下性能更好，即使观察到性能因抑制襟翼展开的后缘涡流而减弱。