• Title/Summary/Keyword: 헬름 홀츠 공명기

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Characterization of Buffeting Noise Through a Rear Window in an Automobile Using LBM (격자 볼츠만법을 이용한 자동차 뒷 창문 버페팅 소음 특성해석)

  • Lee, Songjune;Choi, Hyunggyu;Cho, Munhwan;Ih, Kang-duck;Cheong, Cheolung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.25 no.10
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    • pp.692-699
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    • 2015
  • Buffeting noise through a rear window in an automobile is investigated by using lattice Boltzmann method. The generation mechanism of the buffeting noise can be understood as the resonance mechanism in a Helmholtz resonator, which is driven by the convecting vortex in a shear-layer flow over the neck of the resonator. Two methods to suppress the buffeting noise are proposed, and their effects are quantitatively assessed. Opening front window reduces the observed buffeting tonal noise by 25 dB and the overall SPL by 4 dB, and the installation of a Helmholtz resonator acting as a dynamic damper reduces the tonal component that by 35 dB and the overall SPL by 10 dB.