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Design Improvement via Structural Dynamics Modification - Application to Noise Reduction in Outdoor Unit of Air Conditioner

구조물 동특성 변경을 통한 설계 개선 -공조기 실외기 소음 저감 적용

  • 최상현 (한국과학기술원 기계공학과) ;
  • 박남규 (한국과학기술원 기계공학) ;
  • 박윤식 (한국과학기술원 기계공학과)
  • Published : 2002.05.01

Abstract

The goal of this research is to reduce noise level of an outdoor unit of air conditioner by changing its dynamic characteristics using SDM (structural dynamics modification) technique. At first, the emitting noise was measured and analyzed. The measurement records show the most critical frequency components which influences on the noise level. Then it was tried to move the natural frequencies outside the critical frequency region by SDM. Since it is very difficult to get a reliable FE model of air conditioner, experimentally measured frequency response functions were used to derive sensitivities that are very important to obtain design changes. The positions of modification and the thickness of modifying structures were determined to improve the dynamic characteristics of air conditioner. The recommended design guideline to move its natural frequencies outside the targeting frequency range was obtained. Then in order to prove its effectiveness, the changed design was experimentally tested and found that the SDM result is very effective to reduce not only its vibration but also its emitting noise.

Keywords

References

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