• 제목/요약/키워드: do-noise

검색결과 1,083건 처리시간 0.032초

실험적 방법을 통한 에어컨 실내기의 소음원 검출에 관한 연구 (A Study on Noise Identification of Indoor Air-conditioner Using Experimental Methods)

  • 이성진;오재응;이정윤;강태호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.87-87
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    • 2004
  • An air-conditioner has various noise sources such as a fan noise, a motor noise, and a vibration induced noise. To reduce these noise effectively, noise sources must be identified. Especially in this paper, the structure borne sound radiated from the motor bracket of the indoor air-conditioner is considered. To do this, the operational deflection shape, which is used for understanding of the behavior of the motor bracket at a particular frequency, is obtained and compared with the sound intensity, which is used for the noise identification. Through this study, the noise sources of indoor air-conditioner are defined and the effective noise reduction method is proposed.

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산란을 고려한 수중 프로펠러 소음해석 (Prediction of Marine Propeller Noise Considering Scattering Effect)

  • 김종도;홍석윤;송지훈
    • 한국소음진동공학회논문집
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    • 제21권5호
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    • pp.468-474
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    • 2011
  • Underwater radiated noises from marine vehicles are mostly due to the propulsion systems. Recently, the propeller noise problems are becoming crucial issues in terms of habitability of passenger ships. Especially in military area, propeller noise is directly related to the survivability of submarines and warships, and thus propeller noise analysis and reductions are very important. Generally, propeller noise can be classified into non-cavitating noise and cavitating noise which is dominant. In this paper the methodology of propeller noise analysis is announced and new approach to consider scattering effect is proposed. Unsteady blade surface pressure and sheet cavity volume analyzed with potential based panel method are used as noise source.

Scattering 을 고려한 수중 프로펠러 소음해석 (Prediction of marine propeller noise with scattering effect)

  • 김종도;홍석윤;송지훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2011년도 춘계학술대회 논문집
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    • pp.475-481
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    • 2011
  • Underwater radiated noises from marine vehicles are mostly due to the propulsion systems. Recently, the propeller noise problems are becoming crucial issues in terms of habitability of passenger ships. Especially in military area, propeller noise is directly related to the survivability of submarines and warships, and thus propeller noise analysis and reductions are very important. Generally, propeller noise can be classified into non-cavitating noise and cavitating noise which is dominant. In this paper the methodology of propeller noise analysis is announced and new approach to consider scattering effect is proposed. Unsteady blade surface pressure and sheet cavity volume analyzed with potential based panel method are used as noise source.

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탭이 있는 로터 블레이드의 공력소음에 대한 수치적 연구 (Numerical Investigation of Aerodynamic Noise about Rotor Blade with Tab)

  • 위성용;김도형;정기훈;황창전
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 추계학술대회 논문집
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    • pp.71-74
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    • 2012
  • Generally, tone noise is generated at the rotary wing and helicopter. BVI(Blade-Vortex Interaction) noise is one of the helicopter's tone noise. The BVI noise is governed by tip-vortex characteristics such as vortex size, strength and trajectory. To avoid BVI, many methods have been developed and proposed. In this paper, rotating blade with active tab was numerically investigated to reduce BVI noise. For flow and noise simulation, the lifting surface approach and the acoustic analogy were used. Using numerical methods, the noise directivity and maximum noise position were predicted.

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