The prediction of horizontal axis wind turbine performance in yawed flow using an unsteady prescribed wake model

Abstract

This paper describes a fast, accurate, fully unsteady aerodynamic prediction scheme for the calculation of horizontal axis wind turbine performance in yawed flow. The method couples a prescribed wake vortex model with a semi-empirical unsteady aerofoil model to provide the unsteady aerodynamic response of the blades owing to the cyclic variation of incidence. Predictions from the model are shown to compare well with experiment, both in terms of gross performance prediction and detailed blade loads. Finally, the potential for future improvements to the predictive capability of the model is discussed.