Shock Waves pp 683-688 | Cite as

Noise reduction by using smoothed corner at a duct exit

  • S. M. Liang
  • H. Chen
Conference paper


In this study, the method of a smoothed corner that replaces a commonly used sharp convex corner is employed for noise reduction. The effects of the two parameters — the smoothing angle and the radius of the smoothed surface on the flow structure are investigated. It is found that the larger smoothing angle and the larger radius of the smoothed surface can decrease the strength of the vortex induced by the blast-wave diffraction. In some circumstances, it is found that there is no vortex induced by the blast-wave diffraction. To study the noise reduction, the circumferential pressures at the distances of r = 2D and 4D are measured. The computational results show that the smoothed corner can effectively weaken the vortex strength, and consequently can successfully reduce the noise resulted from the blast wave diffraction around the duct exit. exit


Noise Reduction Vortex Strength Shock Mach Number Secondary Shock Maximum Vorticity 
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Copyright information

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • S. M. Liang
    • 1
  • H. Chen
    • 1
  1. 1.Institute of Aeronautics and AstronauticsNational Cheng Kung UniversityTainanChina

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