Sound Generation by Taylor and Scully Vortexes and the Blade of the Varying Cross Section

Петро Володимирович Лук’янов

Abstract


A problem of the blade vortex interaction noise (BVI) generation has been solved for incoming flux and Taylor, Scully vortexes. Solution for this problem is a closed system of the aeroacoustical equations, which is based on perfect compressible gas model. A behavior of the generated noise has been studied for the different flow velocities and blade thicknesses. Results of the calculations show existence of the two frank regions of the sound existence on the blade shape. The first of it is more resistant for the parameters changing. The second one is a flow region of the instability. These two regions interaction forms far field acoustical pressure distribution. In particular, it has been found that noise characteristics depend on incoming flow velocity and its maximal level depends on blade’s cross section thickness. A sound pressure distribution for Scully vortex is smoother than for Taylor vortex. A frequency distribution of the harmonics level in the noise spectrum has showed low-frequency character of the generated noise. Moreover, at the frequency 700 Hz a local level maximum is seen, which is not present for vortex absence in flow. This fact says about some BVI-energy redistribution in the flux for the higher frequencies generation.

Keywords


Sound generation; BVI Taylor and Scully vortexes interaction

References


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DOI: https://doi.org/10.20535/1810-0546.2014.4.28305

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