Effect of boundary layer suction on performance of a 2 MW wind turbine

Abstract

Fixed geometry of wind turbine blades imposes some limitations on their operation, making them less efficient in off design conditions which is quite common in real operation. In this work, it is shown that flow separation is the main cause of efficiency drop in under rated wind speeds where the pitch regulation system is not effective. To resolve the problem, the boundary layer suction technique is proposed and studied on a MW class wind turbine. It is shown that by creating a narrow slot at the inboard section of the blade and applying different suction intensities, the power coefficient of the rotor can be improved by up to 8.1%. At the same time, the thrust coefficient variation is limited to only 3.8% which is well compensated by structural safety factors.