P.V.Lukianov The effect of blade tip truncation type on the BVI-noise level |
Acoustic bulletin, Vol. 17 ¹ 2, (2015) |
| This paper deals with a problem on BVI-noise generation by a tip-modified rotor blade. Two different cases of blade tip truncation are considered. On the base of the model of inviscid compressible gas, the flow aerodynamical characteristics are obtained and used in further for solving the system of aeroacoustic equations in terms of the acoustic potential and density fluctuations in the sound wave. For a parabolic-truncated tip of the blade, the essential, (10...15) dB, reduction of the vortex-blade interaction noise is discovered. In this case, the acoustic energy demonstrates more smooth distribution over the blade surface then that at non-rounded truncation. In many calculations, for blades truncated with a straight line, the sharp spikes of acoustic density in the vicinity of the angular points emerge. This leads to solution irregularity in mentioned domains. |
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KEY WORDS: sound generation by the flow, Taylor's vortex, blade-vortex interaction, numerical-analytical methods |
| TEXT LANGUAGE: Russian |