The Journal of the Acoustical Society of Korea

The Acoustical Society of Korea (한국음향학회)
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Modal Radiation Efficiency of Swaged Panels

  • Lee, Jong-Hwa (Center for Noise and Vibration Control, Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Ih, Jeong-Guon (Center for Noise and Vibration Control, Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology)
  • Published : 2002.09.01
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Abstract

Swaging technique is frequently used to stiffen thin panels for reducing the vibration levels of the machine or vehicle structure. Because the internal constraints imposed by swages can distort the mode shapes of panels, they affect the sound radiation characteristics. In this paper, the radiated sound field generated by the idealized and baffled finite swaged panel is studied, in which the curved swage section is modeled as an incomplete cylindrical shell. The modal radiation efficiencies are predicted using the transfer matrix concept and compared with those of flat panels. It is observed that the radiation efficiencies of the swaged vibrational modes can increase slightly for frequencies below the critical frequency, while increase of radiation efficiency depends on the mode shapes and other related structural parameters.

Keywords

References

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