Actuator Line Model for Wind Turbine Wake Prediction with PyFR

Since the simulation of a large floating offshore wind turbines (FOWT) wind farm requires significant computational cost, it is important to develop an efficient and accurate numerical model to predict the horizontal axis wind turbine (HAWT) wake structure under complex situations. In this study, a numerical HAWT model based on the actuator line (AL) method and PyFR solver are proposed. In this model, the geometric models of the blades, nacelle, and tower are replaced by body force source terms, which can significantly reduce the computational cost. In addition, the flux reconstruction (FR) method is applied to obtain accurate wake characteristics with less mesh number. The result shows that the proposed AL-PyFR(N&T) model requires only 0.26 million mesh number to achieve a more accurate prediction of the wake velocity and turbulent kinetic energy (TKE), compared to 34.15 million mesh number for the blade-resolved model and 13.5 million mesh number for the AL-IB-LES model. The significant reduction in computational cost enables the simulation of large offshore wind farms.