강판구조모델B의 소음·진동전달문제에 관한 실험적 연구

Abstract

선박의 초기 설계단계에서 소음은 반드시 예측되어져야 한다. 선박과 같은 복잡한 강구조물의 소음, 진동전달문제를 해석하는 방법으로 통계적 에너지 해석법(Statistical Energy analysis) 은 잘 알려져 있다.

본 연구에서는 강구조모델의 소음, 진동레벨을 예측하기 위하여 SEA을 적용하였다. 계산의 정확도를 높이기위하여 두 종류의 파워손실이 파워평형방정식에서 고려되었는데, 하나의 비공진모드에 따른 파워이고 다른 하나는 패널에서 방사되는 손실파워이다.

본 실험적 연구에서 실험모델의 밀폐공간과 패널에 각각 음향기진력,진동기진력을 주어 실험을 수행하였다. 계산결과와 실험결과는 좋은 일치를 보였다. 흡음재의 음압레벨과 진동가속레벨의 저감효과를 알아보기 위하여 실험적 연구도 수행하였다.

The noise levels onboard ship must be predicted in the stage of initial design. It is well known that Statistical Energy Analysis(SEA) provides a theoretical method of approaching these problems including both sound and vibration transmission of complex steel structures such as ships. The authors examined the application of the SEA method to prediction of the sound and vibration level in a steel structure model. To improve the accuracy of the estimation, two kinds of power dissipation are considered in the power flow balance equation, one is the non-resonant power, and the other is the power radiated as sound into the free space. In this experimental study, sound and vibration exciter systems were used in the enclosed space and in the panel respectively.

It was found that the calculated results of sound pressure levels and acceleration levels agreed well with experimental results. The effect of absorption materials on the reduction of the ound pressure levels and acceleration levels in the model was experimentally investigated.

The noise levels onboard ship must be predicted in the stage of initial design. It is well known that Statistical Energy Analysis(SEA) provides a theoretical method of approaching these problems including both sound and vibration transmission of complex steel structures such as ships. The authors examined the application of the SEA method to prediction of the sound and vibration level in a steel structure model. To improve the accuracy of the estimation, two kinds of power dissipation are considered in the power flow balance equation, one is the non-resonant power, and the other is the power radiated as sound into the free space. In this experimental study, sound and vibration exciter systems were used in the enclosed space and in the panel respectively.

It was found that the calculated results of sound pressure levels and acceleration levels agreed well with experimental results. The effect of absorption materials on the reduction of the ound pressure levels and acceleration levels in the model was experimentally investigated.