Experimental Study on High Frequency Vibration Transfer Characteristic of Underwater Cylindrical Shell

doi:2011.25.5.58

J. Ocean Eng. Technol. > Volume 25(5); 2011 > Article

J. Ocean Eng. Technol. 2011;25(5):58-63.
DOI: https://doi.org/10.5574/KSOE.2011.25.5.058

Jung Hyung-Gi,Min Cheon-Hong,Park Han-Il

Agency for Defence Development,Graduate School of Korea Maritime University,Department of Ocean Engineering Korea Maritime University

수중 원통형 쉘 구조물의 고주파 진동 전달특성에 대한 실험적 연구

정현기,민천홍,박한일

국방과학연구소,한국해양대학교 대학원,한국해양대학교 해양공학과

Keywords: Cylindrical shell, High frequency vibration, Excitation, Noise, Underwater vehicle

핵심용어: 원통형 구조물, 고주파 진동, 가진, 소음, 수중운동체

Abstract

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.