Aerodynamic interference characteristics of multiple unit wind turbine based on vortex filament wake model

The downstream wind turbine operating in the wake field will face completely different inflow conditions from the upstream wind turbine, which will show different aerodynamic performance. Therefore, accurate simulation of the wake field is the basis and premise for solving the aerodynamic interference problem. The vortex filament wake model (VFWM) is used to investigate the aerodynamic interference of two wind turbines in parallel, tandem and staggered arrangement. The aerodynamic power, thrust and torque coefficients under non-uniform inflow are defined to measure the relative magnitude of the energy and load suffered by downstream units operating in the wake. In addition, the overall aerodynamic parameters of multiple unit wind turbine (MUWT) at different wind speeds and the overall aerodynamic loads at different wind direction angles are investigated and analyzed. The results show that at rated wind speed, the non-uniform inflow aerodynamic parameters have a greater advantage in describing the aerodynamic performance of downstream units than the commonly defined aerodynamic parameters, because the non-uniform inflow aerodynamic parameters can be maintained near the aerodynamic characteristic parameters of a single unit under wind when varying in a large range of unit spacing. This provides a fast aerodynamic load prediction method for downstream units operating in wake.