Electronic Journal Technical Acoustics ISSN 1819-2408

Liu Zhihong, Yi Chuijie

Acoustic analytical solution of rotating compact sources in frequency domain

language: English

received 05.05.2011, published 01.09.2011

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ABSTRACT

The paper describes a frequency-domain numerical predicting method for sound radiation of rotating compact sound sources. The analytical Green functions of rotating monopole and dipole sources in free space are presented. Sound radiation models are established and characteristics of sound field are studied by numerical simulation. The relationship between radiated sound frequencies and acoustic nature frequency of source, angular frequency and its harmonics can be revealed by the mathematical solution. Results show that radiated sound field has a strong directivity, fundamental frequency transmitting in the rotary shaft direction and harmonics spreading along radial direction and frequency shift phenomena appearing clearly in higher rotating speed of source. The method has theoretical significance for exploring the low-noise rotating machinery.

Keywords: rotating compact sound source, sound radiation, analytical Green function, numerical simulation.

11 pages, 10 figures

Сitation: Liu Zhihong, Yi Chuijie. Acoustic analytical solution of rotating compact sources in frequency domain. Electronic Journal “Technical Acoustics”, http://www.ejta.org, 2011, 8.

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