Comparative study on wind turbine wakes using a modified partially-averaged Navier-Stokes method and large eddy simulation

Abstract A modified Partially-Averaged Navier-Stokes (PANS) turbulence model has been proposed and coupled with the actuator line method (ALM) to investigate the wind turbine wakes. The hybrid model has not yet been applied in wind turbine related simulations, and our work would be the first attempt to evaluate its capabilities in wind turbine wake study. Comprehensive studies have been carried out regarding mesh resolution effect and different levels of inflow turbulence intensity using ALM-PANS method. Numerical simulations of two wind turbines in tandem have been carried out and validated against the popular Large-eddy Simulation (LES) results and experimental data. Relative errors of the rotor power and thrust predictions from ALM-PANS computations against the experimental data are within 5%, which is the same level as LES computations. Profiles of normalized mean velocity and Reynolds stress in the wake have been presented to describe the wake propagation, and the simulation results from PANS and LES are in good agreement with measured data. Due to model simplicity and its low mesh resolution requirement, ALM-PANS has excellent potential in wind farm investigations.