Research on Noise Control for Ventilators with Resonance

来源 :Journal of China University of Mining & Technology(English E | 被引量 : 0次 | 上传用户:suna_lili82
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A study was carried out to control the noise produced by the ventilators at the Luling coalmine, which had caused serious noise pollution to the residents living around the mine for a long time. The main noise source was found to be the dynamic noise at the outlet of the diffuser. The frequency of its peak value was 250 Hz. A special brick with a resonant frequency of 250 Hz was designed to eliminate this noise. The diffusion of a lower frequency noise has been successfully controlled by the installation of a noise-eliminating tower above the diffuser outlet. The detection results show that the noise in the nearby residential area has been lowered to an average 55.3dB(A) in the daytime from 69.8dB(A) and to 48.4dB(A) at night from 65.8dB(A). A study was carried out to control the noise produced by the ventilator at the Luling coalmine, which had caused serious noise pollution to the residents living around the mine for a long time. The main noise source was found to be the dynamic noise at the outlet of the diffuser. The frequency of its peak value was 250 Hz. A special brick with a resonant frequency of 250 Hz was designed to eliminate this noise. The diffusion of a lower frequency noise has been successfully controlled by the installation of a noise- The detection results show that the noise in the nearby residential area has been lowered to an average of 55.3 dB (A) in the daytime from 69.8 dB (A) and to 48.4 dB (A) at night from 65.8 dB (A).
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