ИСТИНА

Experiment based on the MLS technique is very useful in architectural acoustics [1, 2]. The experiment is performed as follows. The investigated area is explored with a quasi-noise signal, whose autocorrelation function is close to a delta function. After a correlation-based data processing one obtains an im-pulse response of the area for given positions of source and receiver. MLS experiment can be useful in aeroacoustics because it allows direct observation of fields diffracted by obstacles having complex shape. For exam-ple, sometimes it is necessary to measure the coefficient o shielding of the en-gine and flow noise by an airfoil. This can be done using the MLS technique. Besides, authors are not aware of any MLS experiments in presence of an air flow. The current work is aimed to field this gap and to find a pulse response corresponding to the acoustical path in presence of turbulent and laminar flows.