Numerical simulation of downwash airflow of rescue helicopter rotor

The helicopters conducting carrier deck operations and performing maritime rescue missions experience significant impacts from the downwash generated by their rotors, affecting both landing performance and the surrounding environment. Addressing the unclear mechanisms of downwash effects during water rescue operations, this study employed Computational Fluid Dynamics (CFD) methods, including overlapping grids, to investigate the operational characteristics of helicopter rotor airflow. Numerical simulations were conducted under various operating conditions, including different inflow velocities and rotor speeds. Based on the calculation results, the implementation process of helicopter rescue operations is proposed. These findings provided valuable guidance for helicopter water rescue operations. The results showed that as the rotor speed of the rescue helicopter gradually increased, the force of the rotor downwash flow on the water surface was greater. Moreover, when the rescue helicopter had an incoming flow velocity, the interference of the rotor downwash flow on the water force could be reduced accordingly.