배기계 디커플러의 음향 특성에 관한 연구

A Study on the Acoustical Characteristics of Exhaust Decoupler

  • 허덕재 (고등기술연구원 제품기술연구센터) ;
  • 임종윤 (아주대학교 대학원/한국 ESI)
  • Hur, Deog-Jae (Product Design Tech. Center, Institute for Advanced Engineering) ;
  • Lim, Jong-Yun (Department of Systems Engineering, Ajou University)
  • 발행 : 2006.09.01

초록

Flexible couplers are widely used for exhaust transmitted vibration reduction in vehicles. This paper describes an investigation into the acoustical characteristics of exhaust flexible coupler by the simulation and testing. Computational acoustic simulation is carrying out to investigate resonance frequency and transmission loss of decoupler using the boundary element method and transfer matrix approach. To confirm the acoustical simulation results of exhaust decoupler, we compare with measured experimental results by the test of transmission loss measurement system. In the comparison with simulation results and tests results, there is correctly fit the resonance frequency and the trend of transmission loss. Also, we show that the acoustical structure of decoupler is analogous to the expended tube or side branch resonator. The characteristics of exhaust decoupler have a marked increase in the acoustic attenuation at the specified frequency bend. Therefore the decoupler is applied to develop the exhaust system not only for the vibration isolator but also for the noise attenuator.

키워드

참고문헌

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