Experimental investigation of the role of instability waves in noise radiation by supersonic jets

Autor:	Victor Kopiev, Sergey Chernyshev, M. Yu. Zaitsev
Rok vydání:	2009
Předmět:	Fluid Flow and Transfer Processes Physics Mechanical Engineering Acoustics General Physics and Astronomy Radiation Instability Radiation pattern Azimuth symbols.namesake Amplitude Harmonics symbols Strouhal number Supersonic speed
Zdroj:	Fluid Dynamics. 44:587-595
ISSN:	1573-8507 0015-4628
Popis:	Existing ideas of instability waves as the main dynamic noise sources in supersonic jets are tested for conformity with the data of acoustic measurements of this noise. Methodologically, the problem consists in the verification of the main principles of Tam’s theory of noise radiation by supersonic jets based on the ideology of instability waves in the shear layer of the jet and their key role in noise generation. Technologically, the study is based on a new technique for measuring the noise, namely, the azimuthal decomposition method developed by the authors. It is shown that on the Strouhal number range from 0.03 to 0.35 the theory satisfactorily describes the radiation pattern of the individual harmonics, while the initial amplitudes of the instability waves are in qualitative agreement with the assumption of their uniform distribution near the nozzle edge.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::b0c208a0697e34c501adf2a6b02992b4 https://doi.org/10.1134/s0015462809040127 Zobrazit plný text záznamu Plný text ve formátu PDF