• The Journal of the Acoustical Society of Korea
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• v.8 no.1
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• pp.31-37
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• 1989

The effectiveness of using a composite beam with constrained visco-elastic layer as a dynamic vibration absorber is investigated. The performance of this absorber is evaluated in terms of displacement transmissibility when to a primary beam with built-in ends and compared to that of the uniform beam absorber. The results of analysis and design show that it is possible to suppress simultaneoulsy the peak transmissibilities at two or more resonance frequencies and the optimal parameters are located within the available viscoelastic material properties.

• Journal of KSNVE
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• v.10 no.2
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• pp.325-330
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• 2000

A dynamic absorber is used to protect the primary vibration system under the steady-state harmonic disturbance. In a number of cases it appears expedient to install several absorbers of smaller masses instead of one. This may be due to the need of distribute the absorber's response along the construction, restrictions on the absorber's installation. So, we studied characteristics of the primary vibration system for the optimal natural frequency ratio and the optimal damping ratio of serial multi-dynamic absorber. Also we obtained the optimum values of the serial multi-dynamic absorber parameters using computer simulation for the damped primary vibration system. In designing multi-dynamic absorber, we presented for the optimal natural frequency and the optimal damping ratio of multi-dynamic absorbers.

• Journal of KSNVE
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• v.7 no.6
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• pp.1039-1048
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• 1997

This paper describes the effects of dual dynamic vibration absorbers attached to a primary vibration system with damping. The efficiency of dual dynamic vibration absorbers was investigated with the height of amplitude ratio at the resonance frequency ratio of the damped vibration system according to mass ratio, natural frequency ratio and damping ratio. The variation of amplitude ratio related to frequency ratio of primary vibration system is verified experimentally and theoretically according to dual dynamic vibration systems using computer program designed to find mutual relationship between two absorbers.

• Journal of the KSME
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• v.30 no.5
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• pp.440-449
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• 1990

펌프의 진동은 설치후 많은 원인이 복합되어 발생하는 것이 일반적이므로 예기치 못하는 경우가 많다. 따라서 진동발생시에 어떻게 체계적인 검토를 거쳐 그 원인을 찾을 것인가, 그리고 원인 제거를 어떻게 효과적으로 수행할 것인가 하는 것이 실제로는 가장 중요한 문제이다. 대형펌 프에서 진동이 발생했을 경우 그 해결을 위해서는 엄청난 경비와 시간이 필요한 경우가 적지 않다. 이러한 측면에서 펌프의 진동을 가장 경계적이고 용이하게 그리고 단시간에 해결할 수 있는 여러 가지 방법이 연구되어야 한다. 그 일례로 실기에 직접 사용할 수 있는 각종의 동흡 진기(dynamic absorber)의 고안과 최적설계 등은 훌륭한 연구과제의 하나이다. 그리고 최근 고 도로 발달한 측정계기, 컴퓨터, 데이터처리 S/W등을 병용한 진동 모니터링(monitoring)에 의한 기기의 이상 진단과 예방 시스템 개발에 관한 연구도 보다 활발히 진행될 필요가 있다.