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

*Agency for Defence Development, Jinhae, Korea**Graduate School of Korea Maritime University, Busan, Korea***Department of Ocean Engineering, Korea Maritime University, Busan, KoreaKEY WORDS: Cylindrical shell 원통형 구조물, High frequency vibration 고주파 진동, Excitation 가진, Noise 소음, Underwater vehicle 수중운동체ABSTRACT: 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 vibra tions above 10 kHz, and these vibrations can cause bad (negativ e) effects on the performance of the sonar. In many previous investigations, nume rical analyses have been used for high frequency vibration prob lems. In this study, an experimental analysis was carried out, and a circular cylind rical shell was considered as the hull structure of an underwat er vehicle. Frequency transfer functions for the circular cylindrical shell were iden tified using an experimental vibration analysis in the air and in a fully-submerged condition. We compare the frequency transfer functions in the a ir and water to obtain hydro-elastic effects. It is found that the dynamic characteristics of the circular cylindrical shell are changed b y varying the response position.교신저자 박한일: 부산광역시 영도구 동삼 2동, 051-410-4326, hipark@hhu.ac.kr본 연구는 20011년 6월 개최된 한국해양과학기술협의회 공동학술대회에 발표된 논문을 근간으로 하고 있음을 밝힙니다 .