The steadily growing air traffic is leading to increased noise pollution. That's why the development of quieter aircraft is imperative. But how can this be achieved for a mid-range aircraft, especially if the fuel efficiency should not suffer by the new designs? Which technologies, configurations and flight procedures have to be combined to end up in a low-noise impact aircraft? And which noise metric should be used to judge whether the new design is really beneficial? These are questions which the researchers are trying to answer within the DLR project SIAM. The long-term goal is to reduce aviation noise by 2050 drastically. This agrees with the EU strategy paper “Flightpath 2050” which calls for a reduction of noise by about 15dB per operation. The project team wants to come as close as possible to this by developing an aircraft with low noise emissions. Hereby, the decision criterium for success is a significant reduction of flyover noise (3-4dB) compared to a conventional aircraft equipped with modern noise abatement technology (LNATRA).
During the first two years, the researchers will follow two different approaches to develop new aircraft configurations. The first approach is about investigating many different variations of tube-and-wing aircraft. The second approach studies unconventional designs like hybrid wing bodies and turbo prop configurations. At the end of the preliminary design phase the researchers will choose the most promising candidate to be further developed during the remaining project period. During this detailed design phase, the researchers will use high fidelity methods in order to make reliable predictions about noise and efficiency of the aircraft.
A crucial part of SIAM is the validation in order to end up with a realistic aircraft which keeps its promises. Besides of demanding simulations, wind tunnel tests within the low-speed acoustic wind tunnel in Braunschweig (DNW-NWB) will be conducted for the reference configuration.
The Institute of Aerodynamics and Flow Technology is responsible for the preliminary design of the tube-and-wing and the hybrid wing body configuration as well as planning and conducting the wind tunnel experiments. Additionally, it supports the preliminary as well as the detailed design with high fidelity simulations for predicting the aerodynamic and acoustic performance of the aircraft.