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Information × Registration Number 0224U001748, 0120U101269 , R & D reports Title Wave fields generated by interacting coherent vortex structures popup.stage_title Head Krasnopolska Tatiana S., д.ф.-м.н. Registration Date 28-01-2024 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2 The sound fields of several coherent vortex structures interacting with each other were calculated using the moment model (MZS-model) of the first and second orders. Sound fields as a result of vortex interaction are calculated using the Lighthill's acoustic analogy under Powell's formulation. It is shown that the computed characteristics of the sound field substantially depend on the order of the moment model describing the vortex structures. The spectrum of the sound field in the description of coherent vortices by point vortices is characterized by a single frequency band, which reflects the motion of the vortex centers of vortices (large-scale vortex movements). Taking into account the inner vortex dynamics (under the transition from the point to elliptic representation of the vortex) leads to the expansion of spectrum and level increasing of calculated sound, which is the result of the interaction of these vortex structures. It is shown that large-scale vortex movements can be modeled by point vortices by the analyzing low frequency band of the sound field. The presence of an upper frequency band in the sound field of interacting vortex spots does not allow us to describe the distributed vortices as point vortices when constructing a sound source, since such a simplification leads to a significant underestimation of the level of the calculated sound field. Since the internal dynamics of the vortices forming the flow leads to a significant increase in a sound field level, in order to reduce the noise emission of the eddy flow, its control should be aimed at reducing the eccentricity of the vortex cores.   Product Description popup.authors Ilchenko Volodymyr M. Ishakova Ludmyla V. Gorskij Yurij V. Konovalyuk Tetyana P. Kot Olexandr O. Krasnopolskaya Tatyana S. Pechuk Evgen D. Filimonov Vitaly Ju. Jarosh Dmytro V. popup.nrat_date 2024-01-28 Close