Porous flow-through fairings for landing gear noise reduction:
experimental acoustic assessment by DLR in AWB windtunnel
INVENTOR focusses on porous flow-through fairings implemented in front of landing gear to decrease noise. Targeted concepts are wiremeshes, perforated plates and metallic wool. A large range of planar samples of different fairings have been first characterized in two facilities at VKI and ONERA, then acoustically down selected at TU-Delft with a simplified (but representative) 2-wheel landing gear (link to NEWS).
The next step is to test the best porous fairings with 3D shape adapted to realistic models of 2-wheel main landing gear. A first set of such tests has been achieved in the aeroacoustic facility AWB at DLR.
Farfield acoustic spectra were obtained from a linear row of microphones, whereas noise maps were computed from measurements with a 96 microphone array in the flyover direction.
A second windtunnel entry with more porous fairings is planned in 2022. The information collected through both test campaign will lead to the selection of the best fairings for further tests:
- on a full scale 2-whell main landing gear in S2A in April 2022 and
- on small scale full aircraft models in DNW-NWB in 2023.
Test set-up in AWB : trailing arm 2-wheel landing gear on a streamlined support