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An Analysis of Internal & External Duct Acoustic Fields by Using a Finite Element Method

  • 이재규 (한국과학기술원, 항공우주공학과(현 삼성항공)) ;
  • 이덕주 (한국과학기술원, 항공우주공학과(현 삼성항공))
  • 발행 : 1993.06.01

초록

Internal & External duct acoustic fields are calculated by using a finite element method. The geometry is assumed as an axisymmetric duct. External acoustic field; outside the duct, and combined internal & external acoustic fields are solved. For both cases a far field's nonreflecting boundary condition is enforced by using a wave envelope element, which is a kind of finite element. First, a pulsating sphere and an oscillating sphere problem are calculated to verify the external problems, and the results are compared with exact solutions. When the wave envelope element is applied at the far boundary, the calculated finite element solutions show good agreements with the exact solutions. Secondly, the combined internal & external duct acoustic fields are calculated and visualized when monopole sources are distributed inside the duct. It is observed that the directivity of sound intensity outside the duct is beaming toward the axis for high frequency sources.

키워드

참고문헌

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