Ongoing research initiatives by the consortium leader Airbus funded by the German Federal Ministry for Economic Affairs and Climate Action (BMWK) aim to enable research and development of future lightweight and acoustically optimized cabin structures by simulations on the ground, thereby reducing cost-intensive flight tests as much as possible. With the "Acoustic Flight-LAB" demonstrator (LuFo IV-4 COCLEA), a realistic cabin fuselage structure has already been set up to investigate the vibro-acoustic properties of aircraft cabins. The subproject UHBR2Noise - DUR "Pressure and Fuselage Structure" by DLR is intended to supplement necessary, previously unavailable input information for cabin noise prediction.
To achieve the next higher technology readiness level (TRL 4) of the "Acoustic Flight-LAB" ground demonstrator, the Institute of Aeroelasticity examines the effect of an increase in cabin pressure relative to the exterior pressure on the structural response of the aircraft cabin. For this purpose, measurements are conducted on a production aircraft in a hangar designed for cabin pressurization tests and on the "Acoustic Flight-LAB" demonstrator. The effect of this pressure difference under cruise conditions cannot be reproduced in current ground simulations. The Institute of Aerodynamics and Flow Technology supplements improved numerical methods to predict the flow-related fuselage excitation. Structural dynamic studies on the "Acoustic Flight-LAB" demonstrator have been previously limited to engine-induced excitations. With the introduction of modern, low-noise UHBR turbomachinery engines, however, the broadband turbulence-related fuselage excitation is decisive for cabin noise during cruise flight. The focus is set on the simulation of the turbulent boundary-layer induced excitation in the cockpit region, for which reliable predictions are unavailable to date.