Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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An Analysis of the Flow Field and Radiation Acoustic Field of Centrifugal Fan with Wedge -The Prediction of the Scattered Sound Field-

웨지가 있는 원심 임펠러의 유동장 및 방사 음향장 해석(II) -원심홴의 산란 음향장 예측-

  • Lee, Deok-Ju (Dept. of Aerospace Engineering, Korea Advanced Institute of Science and Technology) ;
  • Jeon, Wan-Ho (The Digital Appliance Research Center of LG Electronics)
  • 이덕주 (한국과학기술원 항공우주공학과) ;
  • 전완호 (LG전자 디지털 어플라이언스연구소)
  • Published : 2001.09.01
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Abstract

The objective of this study is to understand the generation mechanism of sound and to develop a prediction method for the acoustic pressure field of a centrifugal fan. If the fan is operating at the free field without the casing, the acoustic analogy is a good method to predict the acoustic of the fan. But, the casing gives a dominant effect to the radiated sound field and the scattering effect of casing should be considered. So, in this paper the Kirchhoff-BEM is developed, which can consider the scattering effect of the rigid body. In order to consider the scattering and diffraction effects owing to the casing, BEM is introduced. The source of BEM is newly developed, so the sound field of the centrifugal fan can be obtained. In order to compare the predicted one with experimental data, a centrifugal impeller and a wedge are used in the numerical calculation and the results are compared with the experimental data. Reasonable results are obtained not only for the peak frequencies but also for the amplitudes of the tonal sound. The radiated acoustic field shows the diffraction and scattering effects of the wedge clearly.

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References

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