Aeroacoustic Simulation of an EC145-T2 Rotor in Descent Flight

In recent years a growing ecological awareness in society can be observed and more and more attention has been drawn to low noise concepts for instance. Hence, an improved aeroacoustic predictive capability in the early helicopter design phase is mandatory. For this purpose, IAG enhanced the DLR CFD Code FLOWer with a higher orderWENO method which is now investigated for its industrial applicability for helicopter noise predictions at Airbus Helicopters Deutschland GmbH. By means of a CFD (aerodynamics) - CAA (acoustics) simulation, the EC145-T2 helicopter is investigated in descent flight condition. Subsequently the simulation results are assessed on the basis of flight test data, measured during the EC145-T2 noise certification campaign. In a first step, the isolated rotor only is considered to reduce the computational effort to a complexity realistic for industrial applications. Results show the good capability of the higher order CFD code to resolve the aeroacoustic noise emission within the confidence interval.