Large-eddy simulation of stable boundary layer turbulence and estimation of associated wind turbine loads

Stochastic simulation of turbulent inflow fields commonly used in wind turbine load computations is unable to account for contrasting states of atmospheric stability. Flow fields in the stable boundary layer, for instance, have characteristics such as enhanced wind speed and directional shear; these effects can influence loads on utility-scale wind turbines. To investigate these influences, we use large-eddy simulation (LES) to generate an extensive database of high-resolution ( ∼ 10 m), four-dimensional turbulent flow fields. Key atmospheric conditions (e.g., geostrophic wind) and surface conditions (e.g., aerodynamic roughness length) are systematically varied to generate a diverse range of physically realizable atmospheric stabilities. We show that turbine-scale variables (e.g., hub height wind speed, standard deviation of the longitudinal wind speed, wind speed shear, wind directional shear and Richardson number) are strongly interrelated. Thus, we strongly advocate that these variables should not be prescribed as independent degrees of freedom in any synthetic turbulent inflow generator but rather that any turbulence generation procedure should be able to bring about realistic sets of such physically realizable sets of turbine-scale flow variables. We demonstrate the utility of our LES-generated database in estimation of loads on a 5-MW wind turbine model. More importantly, we identify specific turbine-scale flow variables that are responsible for large turbine loads—e.g., wind speed shear is found to have a greater influence on out-of-plane blade bending moments for the turbine studied compared with its influence on other loads such as the tower-top yaw moment and the fore-aft tower base moment. Overall, our study suggests that LES may be effectively used to model inflow fields, to study characteristics of flow fields under various atmospheric stability conditions and to assess turbine loads for conditions that are not typically examined in design standards. Copyright © 2013 John Wiley & Sons, Ltd.

[1]  Albert A. M. Holtslag,et al.  Estimation of Atmospheric Boundary Layer Parameters for Diffusion Applications , 1985 .

[2]  Larry Mahrt,et al.  Modelling the depth of the stable boundary-layer , 1981 .

[3]  John S. Irwin,et al.  A theoretical variation of the wind profile power-law exponent as a function of surface roughness and stability , 1979 .

[4]  Sukanta Basu,et al.  The WRF Model Forecast-Derived Low-Level Wind Shear Climatology over the United States Great Plains , 2010 .

[5]  Z. Sorbjan.  Effects Caused by Varying the Strength of the Capping Inversion Based on a Large Eddy Simulation Model of the Shear-Free Convective Boundary Layer , 1996 .

[6]  Christopher A. Davis,et al.  Global Distribution and Characteristics of Diurnally Varying Low-Level Jets , 2010 .

[7]  Lance Manuel,et al.  Realistic turbulence inflow generation for wind turbine design , 2012 .

[8]  Turker Ince,et al.  Atmospheric Disturbances that Generate Intermittent Turbulence in Nocturnal Boundary Layers , 2004 .

[9]  Neil Kelley,et al.  The NREL Large-Scale Turbine Inflow and Response Experiment ― Preliminary Results , 2002 .

[10]  Matthias Wächter,et al.  Characterization of wind turbulence by higher‐order statistics , 2012 .

[11]  Herbert J. Sutherland,et al.  On the Fatigue Analysis of Wind Turbines , 1999 .

[12]  J. Michalakes,et al.  A numerical study of the effects of atmospheric and wake turbulence on wind turbine dynamics , 2012 .

[13]  John C. Wyngaard,et al.  Modeling the planetary boundary layer — Extension to the stable case , 1975 .

[14]  George L. Mellor,et al.  A Simulation of the Wangara Atmospheric Boundary Layer Data , 1975 .

[15]  M. Schwartz,et al.  Wind Shear Characteristics at Central Plains Tall Towers: Preprint , 2006 .

[16]  E. Koschmieder.  Taylor vortices between eccentric cylinders , 1976 .

[17]  H. J. J. Jonker,et al.  Local Similarity in the Stable Boundary Layer and Mixing-Length Approaches: Consistency of Concepts , 2008 .

[18]  N. Kelley.  A Case for Including Atmospheric Thermodynamic Variables in Wind Turbine Fatigue Loading Parameter Identification , 1999 .

[19]  Robert M. Banta,et al.  Turbulent Velocity-Variance Profiles in the Stable Boundary Layer Generated by a Nocturnal Low-Level Jet , 2006 .

[20]  J. Cuxart,et al.  Large-Eddy Simulations of the Stable Boundary Layer Using the Standard Kolmogorov Theory: Range of Applicability , 2005 .

[21]  D. L. Sisterson,et al.  Nocturnal boundary-layer wind maxima and the problem of wind power assessment. , 1978 .

[22]  Erik Lundtang Petersen,et al.  Wind power meteorology. Part I: climate and turbulence , 1998 .

[23]  S. Schreck,et al.  U.S. Department of Energy Workshop Report - Research Needs for Wind Resource Characterization , 2008 .

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

[25]  Neil Kelley,et al.  Great Plains Turbulence Environment: Its Origins, Impact, and Simulation , 2006 .

[26]  Takanori Uchida,et al.  Micro-siting technique for wind turbine generator by using large-eddy simulation , 2006 .

[27]  S. Galmarini,et al.  The diurnal evolution of 222 Rn and its progeny in the atmospheric boundary layer during the Wangara experiment , 2007 .

[28]  J. Kaimal,et al.  Spectral Characteristics of Surface-Layer Turbulence , 1972 .

[29]  A. Bechmann,et al.  Hybrid RANS/LES applied to complex terrain , 2011 .

[30]  A. Holtslag,et al.  An inconvenient “truth” about using sensible heat flux as a surface boundary condition in models under stably stratified regimes , 2008 .

[31]  J. Counihan.  Adiabatic atmospheric boundary layers: A review and analysis of data from the period 1880–1972 , 1975 .

[32]  Mark J. Balas,et al.  Identification of Wind Turbine Response to Turbulent Inflow Structures , 2003 .

[33]  W. Bonner.  CLIMATOLOGY OF THE LOW LEVEL JET , 1968 .

[34]  Bowen Zhou,et al.  Large-Eddy Simulation of the Stable Boundary Layer with Explicit Filtering and Reconstruction Turbulence Modeling , 2011 .

[35]  Andrew Swift,et al.  Dynamic LES Modeling of a Diurnal Cycle , 2008 .

[36]  S. Basu,et al.  Large-eddy simulation of stably stratified atmospheric boundary layer turbulence: A scale-dependent dynamic modeling approach , 2005, physics/0502134.

[37]  Jon Wiernga.  Representative roughness parameters for homogeneous terrain , 1993 .

[38]  P. Sagaut.  Large Eddy Simulation for Incompressible Flows , 2001 .

[39]  P. J. Mason,et al.  Large‐eddy simulation of stable atmospheric boundary layers with a revised stochastic subgrid model , 1994 .

[40]  J. Lundquist,et al.  Nocturnal Low-Level Jet Characteristics Over Kansas During Cases-99 , 2002 .

[41]  Arne V. Johansson,et al.  Pressure fluctuation in high-Reynolds-number turbulent boundary layer: results from experiments and DNS , 2012 .

[42]  D. Jager,et al.  Lamar Low-Level Jet Program Interim Report , 2004 .

[43]  Chin-Hoh Moeng,et al.  Large-Eddy Simulation Of The Stably Stratified Planetary Boundary Layer , 2000 .

[44]  Gert-Jan Steeneveld,et al.  Diagnostic Equations for the Stable Boundary Layer Height: Evaluation and Dimensional Analysis , 2007 .

[45]  Larry Mahrt,et al.  Stratified Atmospheric Boundary Layers , 1999 .

[46]  U. Schumann,et al.  Large‐eddy simulation of a neutrally stratified boundary layer: A comparison of four computer codes , 1994 .

[47]  J. Peinke,et al.  Atmospheric turbulence and its influence on the alternating loads on wind turbines , 2011 .

[48]  S. Pope.  Turbulent Flows: FUNDAMENTALS , 2000 .

[49]  A. Holtslag,et al.  An Intercomparison of Large-Eddy Simulations of the Stable Boundary Layer , 2004 .

[50]  B. Jonkman.  Turbsim User's Guide: Version 1.50 , 2009 .

[51]  N. N. Sørensen,et al.  The Bolund Experiment, Part II: Blind Comparison of Microscale Flow Models , 2011 .

[52]  Lance Manuel,et al.  On Space-Time Resolution of Inflow Representations for Wind Turbine Loads Analysis , 2012 .

[53]  Chris Letchford,et al.  Comparison of dynamic subgrid-scale models for simulations of neutrally buoyant shear-driven atmospheric boundary layer flows , 2007 .

[54]  C. Meneveau,et al.  Large eddy simulation study of fully developed wind-turbine array boundary layers , 2010 .

[55]  Efi Foufoula-Georgiou,et al.  Revisiting the Local Scaling Hypothesis in Stably Stratified Atmospheric Boundary-Layer Turbulence: an Integration of Field and Laboratory Measurements with Large-Eddy Simulations , 2006 .

[56]  J. Kaimal,et al.  Turbulenece spectra, length scales and structure parameters in the stable surface layer , 1973 .

[57]  Gert-Jan Steeneveld,et al.  A Conceptual View on Inertial Oscillations and Nocturnal Low-Level Jets , 2010 .