Numerical and Experimental Study of Wake Redirection Techniques in a Boundary Layer Wind Tunnel

Wake Conference 2017

Wang, J.^1 ; Foley, S.^1 ; Nanos, E.M.^1 ; Yu, T.^1 ; Campagnolo, F.^1 ; Bottasso, C.L.^1,2 ; Zanotti, A.^2 ; Croce, A.^2

Wind Energy Institute, Technische Universitat München, Boltzmannstraße 15, Garching bei München

D-85748, Germany^1

Dipartimento di Scienze e Tecnologie Aerospaziali, Politecnico di Milano, Via La Masa 34, Milano

I-20156, Italy^2

关键词: Boundary layer wind tunnel;    High-quality measurements;    Numerical and experimental study;    Particle image velocimetries;    Reynolds shear stress;    Scale-dependent dynamics;    Sub-Grid-Scale models;    Turbulence intensity;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/854/1/012048/pdf
DOI  :  10.1088/1742-6596/854/1/012048

来源: IOP

【 摘 要 】

The aim of the present paper is to validate a wind farm LES framework in the context of two distinct wake redirection techniques: yaw misalignment and individual cyclic pitch control. A test campaign was conducted using scaled wind turbine models in a boundary layer wind tunnel, where both particle image velocimetry and hot-wire thermo anemometers were used to obtain high quality measurements of the downstream flow. A LiDAR system was also employed to determine the non-uniformity of the inflow velocity field. A high-fidelity large-eddy simulation lifting-line model was used to simulate the aerodynamic behavior of the system, including the geometry of the wind turbine nacelle and tower. A tuning-free Lagrangian scale-dependent dynamic approach was adopted to improve the sub-grid scale modeling. Comparisons with experimental measurements are used to systematically validate the simulations. The LES results are in good agreement with the PIV and hot-wire data in terms of time-averaged wake profiles, turbulence intensity and Reynolds shear stresses. Discrepancies are also highlighted, to guide future improvements.