Effects of inflow turbulence on wind turbine loads and wakes for blade-resolved simulations

ORAL

Abstract

Wind turbines in atmospheric boundary layer (ABL) routinely encounter varying wind speeds and turbulence. To optimize the design of turbine blades, it is of great importance to understand the complex interaction between wind turbines and ABL. In this work, the effects of inflow turbulence on the unsteady aerodynamic loads, frequency statistics and wake characteristics are investigated for the NREL Phase VI turbine under axial-flow conditions. Two methods are employed for generating inflow turbulence. The first approach defines turbulence conditions at the inlet and estimates the turbulent kinetic energy decay from the inlet to the turbine location. The second method employs synthetic turbulence generator to inject resolved turbulence. The simulations are performed using Shear-Stress Transport (SST) and Improved Delayed Detached Eddy Simulation (IDDES) turbulence models. Comparison of the power spectral density (PSD) based on the thrust coefficient as well as the resulting Strouhal number is performed. The effects on velocity deficit and turbulent intensity are also examined both in the near- and far-field wake regions.

*This work was authored by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding provided by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Wind Energy Technologies Office. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes. The research was performed using computational resources sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy and located at the National Renewable Energy Laboratory.

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Presenters

  • Shreyas Bidadi

    • National Renewable Energy Laboratory

Authors

  • Shreyas Bidadi

    • National Renewable Energy Laboratory

  • Ganesh Vijayakumar

    • National Renewable Energy Laboratory

  • Ashesh Sharma

    • National Renewable Energy Laboratory

  • Michael A Sprague

    • National Renewable Energy Laboratory