An improved prediction model of vortex shedding noise from blades of fans

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• 作者：Huashu Dou ; Zhehong Li ; Peifeng Lin ; Yikun Wei ; Yongning Chen…
• 关键词：vortex shedding noise ; broadband noise ; boundary layer separation ; fan
• 刊名：Journal of Thermal Science
• 出版年：2016
• 出版时间：December 2016
• 年：2016
• 卷：25
• 期：6
• 页码：526-531
• 全文大小：551 KB
• 刊物类别：Physics and Astronomy
• 刊物主题：Physics
  Mechanics, Fluids and Thermodynamics
  Engineering Fluid Dynamics
  Engineering Thermodynamics and Transport Phenomena
  Chinese Library of Science
  
• 出版者：Science Press, co-published with Springer-Verlag GmbH
• ISSN：1993-033X
• 卷排序：25

文摘

The main source of the noise of an axial flow fan is the fluctuating pressure field on blade surfaces caused by the shedding of vortices at the trailing edge of blades. An analytical model to predict the vortex shedding noise generated at the trailing edge of blades of axial flow fans was proposed by Lee in 1993. In this model, for mathematical convenience, an idealized vortex street is considered. However, the agreement between the analytical results and the experimental data needs to be improved because of the simplification about the Karman vortex street in the wake of blade. In the present study, a modified model is proposed based on the prediction model by Lee. The boundary layer theory is used to analyze and calculate the boundary layer development on both the pressure and the suction sides of blades. Considering the effect of boundary layer separation on the location of noise source, the predicted overall sound pressure level compares favorably with the experimental data of an axial fan. In the calculation of A-weighted sound pressure level (L_A), considering the effect of static pressure on radiate energy, the predicted broadband noise with the modified model compares favorably with the experimental data of a multiblade centrifugal fan.