Experimental Study on High Frequency Vibration Transfer Characteristic of Underwater Cylindrical Shell Jung, Hyung-Gi; Min, Cheon-Hong; Park, Han-Il;
Underwater vehicles such as UUVs (Unmanned Underwater Vehicles) and ROVs (Remotely Operated Vehicles) use sonar to detect their underwater environment or other underwater vehicles. The underwater vehicles designed recently have an electrical power system with high rotational speed. This system can generate high frequency vibrations above 10 kHz, and these vibrations can cause bad (negative) effects on the performance of the sonar. In many previous investigations, numerical analyses have been used for high frequency vibration problems. In this study, an experimental analysis was carried out, and a circular cylindrical shell was considered as the hull structure of an underwater vehicle. Frequency transfer functions for the circular cylindrical shell were identified using an experimental vibration analysis in the air and in a fully-submerged condition. We compare the frequency transfer functions in the air and water to obtain hydro-elastic effects. It is found that the dynamic characteristics of the circular cylindrical shell are changed by varying the response position.
Cylindrical shell;High frequency vibration;Excitation;Noise;Underwater vehicle;
Min, C.H., Park, H.I., Kim B.M. and Kim, S.P. (2010). "An Experimental Study on the Hydro-elastic Analysis of a Circular Cylindrical Shell", The Ninth (2010) ISOPE Pacific/Asia Offshore Mechanics Symposium, ISOPE, Busan, Korea, pp 275-281.
Min, C.H., Park, H.I., Jung H.G. and Yoo, J.H. (2011). "An Experimental Study on High-Frequency Vibration Analysis of a Circular Cylindrical Shell in Contact with Water", The Twenty-first International Offshore(Ocean) and Polar Engineering Conference, ISOPE, Maui, Hawaii, USA, pp 322-326.
Ugurlu, B. and Ergin, A. (2008). "A Hydroelastic Investigation of Circular Cylindrical Shells-containing Flowing Fluid with Different End Conditions", Journal of Sound and Vibration, Vol 318, pp 1291-1312.