Active Lining for the Reduction of Rotor Noise

Abstract

The participants of the EU-project ACASIAS develop advanced concepts for aero-structures with multifunctional capabilities. Within work package 3 an active system for noise reduction is integrated into a lining panel. The application scope includes current propeller driven aircraft and future aircraft with counterrotating open rotor (CROR) engines. The drawback of these CO2-efficient engines is their high sound emission in the frequency band up to 500 Hz. Active noise reduction systems are able to achieve performance in this frequency band while passive sound insulation materials fall behind. In this paper an integration concept for the actuators and sensors of an active noise reduction system is presented. It includes the protection of the components from humidity, dust, etc. and the integration into industrial manufacturing processes. A tool- and connector-free assembly of the components allows a fast and reliable maintenance. The concept is implemented on a lining with size 1300×1690 mm^2.