It is crucial to know the mechanism of low-frequency noise from the leading-edge slat, which can guide an advanced active and passive control of slat noise. According to the highly reliable Large Eddy Simulation (LES), this paper reveals the mechanism of slat noise using the method of Dynamic Mode Decomposition (DMD). The results indicate that the dipole features of slat noise come from the collision between large scale vortexes in the free shear layer and the lower surface of the slat. There is a close loop feedback mechanism of flow-acoustic coupling existing between large scale vortexes and low-frequency acoustic waves from the reattachment point. Based on this mechanism, a theoretical predictive model is also proposed and verified.
WEI Jiayun
,
LI Weipeng
,
XU Siwei
,
ZHAO Keliang
,
SUN Yifeng
. Analysis of mechanism of slat low frequency noise based on zonal DMD[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2018
, 39(1)
: 121469
-121469
.
DOI: 10.7527/S1000-6893.2017.121469
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