• 한국음향학회지
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• 제37권5호
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• pp.285-291
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• 2018

본 연구에서는 차량에 장착되는 파노라마 썬루프 디플렉터의 각도에 따른 개구부 주변 유동 특성을 분석하고 공력소음에 미치는 영향을 확인하였다. 파노라마 썬루프 개방 후 주행 시 공력소음을 저감하기 위해 메쉬 디플렉터를 장착하는데, 후방향인 기존 메쉬 디플렉터 각도를 전방향으로 변경하였을 때 유동 변화와 공력소음 기여도를 분석하였다. 이를 위하여 CAT(Computer Aided Test)와 실차 풍동 평가를 진행하였으며, 전방경사형 디플렉터에서 기존 디플렉터 대비 원활한 유동의 흐름과 유동 방향의 상향으로 공력소음이 개선되는 것을 확인하였다. 전방경사형 디플렉터 적용 시 동등한 원가에서 공력소음을 개선할 수 있을 것으로 기대된다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1104-1108
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• 2007

Automobile sunroof buffeting is the tonal noise of low frequency around 20Hz. It occurs due to the acoustic feedback process between the shear layer detached from the leading edge of sunroof opening and the Helmholtz resonator-like property of a car cabin. In this paper, PIV visualization technique is applied to the unsteady flow field around sunroof opening of an SUV in the full-scale automotive wind tunnel in order to find out buffeting mechanism. A phase-marking PIV measurement method, in which image and sound pressure are recorded simultaneously, and a phase-rearrangement post-processing program were developed for capturing noise-related velocity fields without expensive synchronization systems. Through this study, some characteristics of the real-car sunroof shear layers under various deflector conditions were identified and these results can provide insights into the noise reduction mechanism of the tube-type deflector.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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• pp.166-169
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• 2005

The best sunroof wind noise quality is mainly related to the sunroof deflector which affects both low-speed buffeting and high-speed aerodynamic noise. An automatic deflector-moving and noise-measuring apparatus is developed to obtain hundreds of measuring data which haven't been available by hand. With an additional program for fast and easy noise analysis, this device leads quickly to the better position and angle of the deflector. Now, the 'better' means the lower noise level and the robuster design solution. From these kinds of better solutions, more meaningful guidelines on the deflector design and sunroof wind noise reduction can be suggested.