Fully-Coupled Simulations of the Rotorcraft / Ship Dynamic Interface

A fully- coupled simulation tool has been developed to analyze the rotorcraft/ship dynamic interface problem. An existing computational fluid dynamics code and a flight dynamics simulation model have been coupled for this purpose. The flight dynamics model provided the location and orientation of the helicopter and the main rotor as well as the blade loads while the computational fluid dynamics code provided local air velocities. Computations have been performed for a UH-60A hovering behind an aircraft hangar and approaching an LHA class ship. For the solutions the flowfield is assumed to be inviscid and atmospheric turbulence and boundary layer effects have been neglected. The results show that when the helicopter is operating in ground effect or close to solid structures, the interactions between the airwake and the rotor wake can invalidate the one-way coupled solutions.