In this paper, the aerodynamic, mechanical and electromagnetic sources of noise within a fan are considered. The results of measurement are also included and the observed phenomena are described. The concept of fan similarity for the prediction of sound power is described and various proposed similarity laws discussed. It is concluded that there are not universally applicable similarity laws and that there is not a linear relationship between sound power and fan speed, even at a fixed rating point on the fan's characteristic.
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References
1.
PhelanJ.J., RussellS.H. and ZeluffW.C., A Study of the Influence of Reynolds Number on the performance of Centrifugal Fans A.S.M.E. Paper No. 78–WA/PTC-3, 1978.
2.
LighthillM.S., On Sound Generated Aerodynamically Proc. Royal Society, 1952, A211, 564.
3.
GutinL., Uber das Schollfeld einer Rotierenden Luftschrabe, Physik. Zeits Sowjet Union91936.
4.
CurieN., The Influence of Solid Boundaries upon Aerodynamic Sound Proc. of the Royal Society, 1955.
5.
Ffowcs-Williams and Hawkings, Theory Relating to Noise of Rotating Machinery, Journal of Sound and Vibration1969, 10(1), 10–21.
6.
NeiseW., Fan Noise – Generation Mechanisms and Control Methods1988, Proc. Inter-Noise 88, Vol. 2, 767–776.
7.
TylerJ.M. and SofrimT.B., Axial Flow Compressor Noise Studies Society of Automotive Engineers Transactions, 1962.
8.
YangS.J., Low Noise Electric Motors Oxford University Press, 1981.
9.
GlewC.N., The Origins and Control of Induction Motor Noise Paper 3, Industrial Motors Symposium, GEC Ltd., 1977.
