Numerical Study of Nacelle Wind Speed Characteristics of a Horizontal Axis Wind Turbine under Time-Varying Flow

Nacelle wind speed transfer function (NTF) is usually used for power prediction and operational control of a horizontal axis wind turbine. Nacelle wind speed exhibits high instability as it is influenced by both incoming flow and near wake of a wind turbine rotor. Enhanced understanding of the nacelle wind speed characteristics is critical for improving the accuracy of NTF. This paper presents Reynolds-averaged Navier–Stokes (RANS) simulation results obtained for a multi-megawatt wind turbine under both stable and dynamic incoming flows. The dynamic inlet wind speed varies in the form of simplified sinusoidal and superposed sinusoidal functions. The simulation results are analyzed in time and frequency domains. For a stable inlet flow, the variation of nacelle wind speed is mainly influenced by the blade rotation. The influence of wake flow shows high frequency characteristics. The results with stable inlet flow show that the reduction of the nacelle wind speed with respect to the inlet wind speed is overestimated for low wind speed condition, and underestimated for high wind speed condition. Under time-varing inflow conditions, for the time scale and fluctuation amplitude subject to the International Electrotechnical Commission (IEC) standard, the nacelle wind speed is mainly influenced by the dynamic inflow. The variation of inflow can be recovered by choosing a suitable low pass filter. The work in this paper demonstrates the potential for building accurate NTF based on Computational Fluid Dynamic (CFD) simulations and signal analysis.

[1]  J. Sørensen,et al.  Wind turbine wake aerodynamics , 2003 .

[2]  Kyungnam Ko,et al.  Application of the Nacelle Transfer Function by a Nacelle-Mounted Light Detection and Ranging System to Wind Turbine Power Performance Measurement , 2019 .

[3]  W. Tian,et al.  Experimental investigation on the wake interference among wind turbines sited in atmospheric boundary layer winds , 2017 .

[4]  Andreas Bechmann,et al.  Near wake Reynolds-averaged Navier–Stokes predictions of the wake behind the MEXICO rotor in axial and yawed flow conditions , 2014 .

[5]  Gunner Chr. Larsen,et al.  A Simple Wake Calculation Procedure , 1988 .

[6]  S. Wagner,et al.  An experimental and numerical study of the vortex structure in the wake of a wind turbine , 2000 .

[7]  Christian Masson,et al.  2D and 3D numerical simulation of the wind-rotor/nacelle interaction in an atmospheric boundary layer , 2011 .

[8]  F. Porté-Agel,et al.  A Wind-Tunnel Investigation of Wind-Turbine Wakes: Boundary-Layer Turbulence Effects , 2009 .

[9]  Muyiwa S. Adaramola,et al.  Performance and near wake measurements of a model horizontal axis wind turbine , 2012 .

[10]  P. R Ebert,et al.  The near wake of a model horizontal-axis wind turbine , 2001 .

[11]  Hui Hu,et al.  Dynamic wind loads and wake characteristics of a wind turbine model in an atmospheric boundary layer wind , 2012 .

[12]  J. F. Ainslie,et al.  CALCULATING THE FLOWFIELD IN THE WAKE OF WIND TURBINES , 1988 .

[13]  Christian Masson,et al.  Effects of Wind Turbine Rotor Modelling on Nacelle Anemometry , 2013 .

[14]  Søren Juhl Andersen,et al.  Validation of four LES and a vortex model against stereo-PIV measurements in the near wake of an actuator disc and a wind turbine , 2016 .

[15]  G. Bussel,et al.  Experimental and numerical investigation of tip vortex generation and evolution on horizontal axis wind turbines , 2016 .

[16]  H. Hangan,et al.  Flow characterization in the near‐wake region of a horizontal axis wind turbine , 2016 .

[17]  B. Koren,et al.  Review of computational fluid dynamics for wind turbine wake aerodynamics , 2011 .

[19]  Niels N. Sørensen,et al.  Characterization of the unsteady flow in the nacelle region of a modern wind turbine , 2011 .

[20]  David Wood,et al.  The near wake of a model horizontal-axis wind turbine—I. Experimental arrangements and initial results , 1997 .

[21]  F. Porté-Agel,et al.  Near-wake flow structure downwind of a wind turbine in a turbulent boundary layer , 2011, Experiments in Fluids.

[22]  Kurt Schaldemose Hansen,et al.  Alternative approach for establishing the Nacelle Transfer Function , 2016 .

[23]  F. Porté-Agel,et al.  Large-Eddy Simulation of Wind-Turbine Wakes: Evaluation of Turbine Parametrisations , 2011 .

[24]  G.J.W. Van Bussel,et al.  Experimental investigation of the root flow in a horizontal axis wind turbine , 2014 .

[25]  Rozenn Wagner,et al.  Uncertainty of power curve measurement with a two‐beam nacelle‐mounted lidar , 2016 .

[26]  N. Jensen.  A note on wind generator interaction , 1983 .

[27]  Christian Masson,et al.  Numerical study of turbulent flow around a wind turbine nacelle , 2006 .

[28]  I. Dobrev,et al.  Exploration of the vortex wake behind of wind turbine rotor , 2007 .

[29]  Shun Kang,et al.  Investigations on the Unsteady Aerodynamic Characteristics of a Horizontal-Axis Wind Turbine during Dynamic Yaw Processes , 2019, Energies.

[30]  Trevor M. Young,et al.  An assessment of commercial CFD turbulence models for near wake HAWT modelling , 2018 .

[31]  P. Cochat,et al.  Et al , 2008, Archives de pediatrie : organe officiel de la Societe francaise de pediatrie.