1 research outputs found
An overview of DLR compound rotorcraft aerodynamics and aeroacoustics activities within the CleanSky2 NACOR Project
The challenge of increasing range and speed of a rotorcraft is encountered in the scope of the European CleanSky2
“Fast Rotorcraft” project by Airbus Helicopters with the compound helicopter design RACER
(RapidAndCostEfficientRotorcraft) for which the box wing and the tail parts designs are respectively protected by
patent. This paper presents the DLR contributions to the RACER development. This includes the aerodynamic
design of the wing and tail section as well as an overall assessment of performance and noise. In a first step the
aerodynamic properties of the configuration are evaluated both isolated and with consideration of the main rotor and
lateral rotor interferences by the use of actuator discs. In the second step, the investigated possibilities to improve
the configurations performance are described. These include airfoil design for improved high lift performance of the
wing and tail section, an optimization of the box wing circulation distribution on the upper and lower wing.
Additionally, the intersection fairings were improved and the efficiency of the trim flaps was evaluated. In this
regard, it could be determined for which cases an isolated approach is appropriate and when the rotor interference
should be considered. At the end the evaluation of the aero acoustics of the configuration is conducted. The applied
configuration shows good aerodynamic characteristics with some further cruise and off design optimization
potential