On the Possibility of Using a Single Time Realization for Investigating Noise from Vortex Rings

Abstract

The possibility of using a single time realization of a vortex ring to study its aeroacoustic properties is considered. For each realization, averaging is performed over six microphones located around the path of the ring at the same distance from its axis. Spectra obtained as a result of such averaging are presented. It is shown that the specific features of noise from an individual vortex ring agree well with earlier results when averaging over an ensemble of realizations. It is proposed for the first time to localize the sources of noise produced by a vortex ring during its motion using a multimicrophone array with a beamforming algorithm adapted for the considered problem. The position of the noise sources on the localization map is in good agreement with the trajectory measurements of the vortex ring. A beamforming array was used to obtain the averaged spectra of single realizations corresponding to localization of sources for different delays from the moment of vortex launch.