The EROS Aerodynamic Analysis Tool: an Application Towards the Prediction of Helicopter Rotor Noise in Hover

GEROS and EROS are respectively a grid generator and an Euler solver for the aerodynamic simulation of the unsteady flow fields around wings and multibladed rotor configurations. Thier development, carried out within the Brite/Euram EROS project, has involved rotorcraft manufacturers, reserach centres and universities. The grid generator covers fully the dunamic geometrical problems that need to be addressed: surface grid generation, volume grid generation, volume grid adaptation/deformation/rotation/positioning, dynamic connectivity and animation/prototyping of the dunamic geometries. The Euler solver embeds two solution methodologies implemented within the dual-time method, and is able to solve the Euler equations on deforming and/or overlapping grids. This paper discusses the capabilities of both GEROS and EROS codes and presents the results of the coupling between the EROS aerodynamic solver and the CIRA aeroacoustic code HERNOP3 for the prediction of high-speed impulsive (HSI) noise in hover.