• 한국소음진동공학회논문집
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• 제21권10호
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• pp.905-915
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• 2011

The free flexural vibration of a hanged clamped-free cylindrical shell partially submerged in water with gap from bottom is investigated. The fluid is assumed to be inviscid and irrotational. The cylindrical shell is modeled by using the Rayleigh-Ritz method based on the Sanders shell theory. The kinetic energy of the fluid is derived by solving the boundary-value problem related to the fluid motion. The natural vibration characteristics of the partially submerged cylindrical shell are discussed with respect to the added virtual mass approach. In this study, experiments were carried out to confirm theoretical results. It was found that theoretical prediction is in good agreement with experimental results.

• 한국소음진동공학회논문집
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• 제25권1호
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• pp.33-39
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• 2015

This paper investigates the underwater acoustic radiation from a periodically stiffened cylindrical shell excited resiliently mounted machinery. Underwater acoustic radiation is important to a submarine. Generally, submarine structure can be modeled as stiffened cylindrical shell immersed in water. Analytical model is derived for the far-field acoustic radiation from machinery installed inside cylindrical shell. The analytical model includes the effect of fluid loading and interactions between periodic ring stiffeners. Transmitted force from machine to a shell through isolator can be different by the impedance of shell. In this paper the effect of a shell impedance for acoustic radiation is investigated. Impedance of a shell should be considered if thickness of a shell is thin.