Aeroacoustic Research at DLR

Abstract

DLR research in the area of aeroacoustics pertains to (1) the noise of helicopters, where experimental investigations on model of full-scale rotors are conducted to study the noise generation and radiation mechanisms of helicopter main- and tail rotors to further the understanding of the underlying physical mechanisms and to find technical means to reduce the noise, employing e.g. blade control techniques (higher harmonic control and individual blade control), as well as advanced rotor blade geometries. - Theoretical efforts pertain to the development and application of boundary element methodsfor blade-vortex interaction noise as well as to the combination of CFD and Kirchhoff-methods for high-speed impulsive noise. (2) airframe noise, i.e. the noise generated by deployed landing gears and wing high lift devices of subsonic jet-aircraft in the configuration for landing approach. Here, in the context of industrial contracts or specific national of European Programs, DLR investigates the underlying aeroacoustic source mechanisms and develops technical means to reduce the aerodynamically generated noise of such critical components. Efforts on developing Computational Aeroacoustics (CAA) methods to predict the noise from fowler flap side edges noise are conducted within a national project "SWING".