Validating the Beddoes-Leishman Dynamic Stall Model in the Horizontal Axis Wind Turbine Environment

Ricardo Balbino Santos

Key information

Authors:

Ricardo Balbino Santos (Ricardo Balbino Santos Pereira)

Supervisors:

João Manuel Melo de Sousa (João Manuel Melo de Sousa)

Published in

09/28/2010

Abstract

The European Union developed a project named MEXICO, providing a database of aerodynamic data for a horizontal axis wind turbine (HAWT). The aim of this master thesis was to choose and implement a dynamic stall (DS) model and to compare it with the MEXICO data obtained at high wind speeds in the presence of yaw misalignment. It was chosen to implement the DS model in a Blade-Element Momentum (BEM) code, and consequentially two BEM approaches were compared with MEXICO data obtained at moderately high wind speeds. Posteriorly the Beddoes-Leishman DS model was tailored to the HAWT environment, and validated against unsteady airfoil wind tunnel data. Different leading edge stall criteria were tested and good agreement was found. The rotational augmentation of the aerodynamic coefficients was also investigated using an inverse BEM method and empirical rotational corrections have been applied. Finally the rotational corrections and the DS model were implemented in the BEM code, and the results were compared with high wind speed yawed flow MEXICO data. Reasonable to good agreement was found, and it was clear that including the dynamic stall model improved the computational results. The experimental trends observed were not always captured by the model, but the magnitude of the loads occurring over a revolution was well predicted.