Blade-Resolved CFD Simulations of a Periodic Array of NREL 5 MW Rotors with and without Towers

A fully resolved (FR) NREL 5 MW turbine model is employed in two unsteady Reynolds-averaged Navier–Stokes (URANS) simulations (one with and one without the tower) of a periodic atmospheric boundary layer (ABL) to study performance an infinitely large wind farm. The results show that power reduction due tower drag about 5% under assumption driving force ABL unchanged. Two additional using actuator disc (AD) are also conducted. AD FR nearly identical tower-induced reductions speed above farm, supporting argument sufficient predict farm blockage effect. We investigate feasibility performing delayed-detached-eddy (DDES) same domain setup. complex turbulent flow characteristics within such as interaction large-scale hairpin-like vortices smaller-scale blade-tip vortices. computational cost DDES required for given number rotor revolutions found be similar corresponding URANS simulation, but sampling period obtain meaningful time-averaged seems much longer existence long-timescale fluctuations.