High-resolution numerical simulation of an innovative overlapping dual-rotor wind turbine with intersecting spiral vortex filaments

In recent years, wind turbines—particularly offshore floating wind turbines—have grown significantly in size. However, this trend has raised critical challenges related to platform stability and associated costs. Recent projects, such as the MingYang Tiancheng floating offshore wind turbine, have proposed innovative dual-rotor configurations mounted on a single platform, offering promising solutions to these large-scale design constraints. Building upon this concept, the present study investigates a novel configuration involving overlapping dual-rotor wind turbines, aiming to enhance both the power output per unit swept area and the total energy production of a single floating platform. First, high-resolution numerical simulation is adopted for the intersecting spiral vortex filaments of dual-rotor wind turbines. Next, a comparative analysis was carried out between counter-rotational and co-rotational dual-rotor wind turbines and conventional single-rotor turbines. The dual-rotor configurations were shown to generate stronger tip vortices and faster wake recovery, indicating their superior potential for wind farm deployment. Finally, various overlapping distances were evaluated. Results reveal that overlapping configurations can significantly improve power generation per unit width, which provides important guidance for the compact and efficient layout of next-generation offshore wind farms.