Wind turbine enhancement via Active Flow Control Implementation

TL;DR

This research demonstrates how implementing Active Flow Control with Synthetic Jets on wind turbine blades can significantly improve efficiency by delaying boundary layer separation, with a detailed CFD-based optimization process.

Contribution

The paper introduces a CFD-based optimization method for AFC parameters on wind turbine blades, enhancing power output by controlling boundary layer separation.

Findings

AFC can reattach separated boundary layers, increasing turbine power.

Optimization of AFC parameters leads to significant efficiency gains.

The procedure provides a framework for performance enhancement under various conditions.

Abstract

The present research aims to enhance the efficiency of a DTU-10MW Horizontal Axis Wind Turbine (HAWT) via Active Flow Control (AFC) implementation and using Synthetic Jets (SJ). In the initial part of the study the flow around two airfoil sections cut along the wing turbine blade and for a wind speed of 10m/s is simulated using CFD-2D-RANS-K{\omega}-SST turbulence model, in order to obtain the time averaged boundary layer separation point and the associated vortex shedding frequency. This information is used, on a second stage of the paper, to set, in one of these two airfoils where the boundary layer is having an early separation, two of the AFC parameters while optimizing the remaining three. The optimization is performed employing a parametric analysis and demonstrates that a considerable WT power increase can be obtained when managing to reattach the former separated boundary layer. This is further clarified thanks to the energy assessment presented in the final part of the paper. Although the AFC optimization needs to be extended for the rest of the blade sections, the procedure outlined in the present research clarifies the different steps to be followed to optimize the performance of any HAWT under any operating conditions. The Reynolds numbers associated to the respective airfoil sections analyzed in the present manuscript are Re = 14.088 e6 and Re = 14.877 e6, the characteristic length being the corresponding chord length for each airfoil.