Non-Synchronous Measurements for Sound Source Localisation of a High-Lift Common Research Model in the Wind Tunnel Test

The sound source localisation of the high-lift device is an essential means of analyzing and controlling aircraft noise levels. The High-lift Common Research Model (HL-CRM) is tested in this paper, depending on the FL-IO aero acoustic wind tunnel. However, the high-frequency sound source localisation of HL-CRM could not be realized due to the sparse microphone spacing on the array surface. A high-frequency aerodynamic noise source localisation method via non-synchronous measurements in wind tunnel tests is developed in this paper. The non-synchronous measurements of the HL-CRM in the wind tunnel are first performed, then the cross-spectral matrix is filled by using a fast iterative shrinkage threshold algorithm for the measured data, and finally combines with the CLEAN-SC algorithm to achieve high-frequency sound source localisation of the HL-CRM. The results indicate that the non-synchronous measurements technology can be applied in the wind tunnel test and achieve more accurate acoustic imaging at higher frequencies.