RACER Aero-acoustic Propeller Analysis and Design

This work investigates the lateral rotors of the RACER, Airbus Helicopters high-speed demonstrator. These lateral rotors also defined as propellers, provide anti-torque in hover and thrust in cruise flight. The first action was to better understand the complex aerodynamic interactions that the propellers undergo in hover and cruise flight. Then, in view of optimizing the aerodynamic and particularly the acoustic performance of the propellers, their design was adapted to exploit synergistically the installation effects. Optimization included airfoil optimization and blade design, taking into account structural and manufacturing constraints. By using a smart choice of multifidelity simulations, ONERA improved drastically the aerodynamic and acoustic performance of the RACER.