http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
알베리히 무반향 코팅재 효과를 고려한 잠수함의 음향 표적강도 해석
권현웅,홍석윤,김화묵,송지훈,Kwon, Hyun-Wung,Hong, Suk-Yoon,Kim, Hwa-Muk,Song, Jee-Hun 해양환경안전학회 2013 해양환경안전학회지 Vol.19 No.4
음향 표적강도는 잠수함의 생존성을 보장하기 위한 중요한 설계 고려 요소이다. 잠수함이 대형화 됨에 따라 음향 표적강도 저감을 위한 대표적인 방법으로 알베리히 무반향 코팅재가 널리 사용되고 있다. 본 논문에서는 규칙적으로 배열된 알베리히 무반향 코팅재 단위 셀에 대해 유한요소법을 이용하여 음압 투과반사 계수를 해석하였다. 해석 결과는 문헌의 실험결과와 비교 검증하였다. 또한, 잠수함의 음향 표적강도 계산시 해석된 코팅재의 입력 임피던스를 이용하여 반사계수를 고려하였다. 마지막으로 알베리히 무반향 코팅재 적용에 따른 음향 표적강도 감소 효과(Case 1: 10dB, Case 2: 6dB)를 확인하였다. Acoustic target strength (TS) is one of the most considerable design elements for survival capacities of the submarine. It needs to reduce acoustic TS that submarines are getting larger and larger, Alberich anechoic coatings are widely used as the representative method. In this paper, the finite element method (FEM) is used to analyze the reflection and transmission coefficients of Alberich anechoic coatings, which have periodic unit cells. The FEM results are compared with experimental results in the literature. Moreover, acoustic TS for the submarine is analyzed by using that result. Finally, it is shown that acoustic TS (Case 1: 10dB, Case 2: 6dB) are reduced due to the use of Alberich anechoic coatings.
5인치 함포 포열 고압탄 사격 시험평가 체계 개발 연구
한규진,김봉수,이호준,김승호,김화묵,이봉수,박노석,황지석,안현진 국방기술품질원 2023 국방품질연구논집 Vol.5 No.2
The core component of a 5-inch naval gun-firing system, the gun barrel, senables loaded ammunition to fly to the target point of impact. A high-pressure firing test is performed after the gun barrel is manufactured. The final performance test checks the structural stability of the gun barrel by conducting a firing test at a pressure of 1OO% or more of the operating pressure (55,000 psi). Previously, a gun barrel manufactured by the source company BAE Systems and verified through a high-pressure firing test at the U.S. Navy’s firing test site was introduced and applied to a 5-inch naval gun. However, because of a shortage of detonators owing to accidents involving high-pressure ammunition detonators and the U.S. Navy’s national defense policy (Defense Priorities and Allocation System), the delivery of gun barrels was delayed. Therefore, high-pressure firing tests were conducted at domestic firing test sites through consultation with related agencies and revision of the national defense standards for the 5-inch naval gun. In this study, high-pressure firing tests conducted overseas were converted into domestic tests. The H-WIA aims to develop a test evaluation system for high-pressure firing tests that can be conducted in a domestic test environment. In addition, the overseas test evaluation takes approximately 14 weeks, including transportation in the United States, and the test cost is approximately 500 million won, but the schedule for conducting the test evaluation in Korea is two weeks and the cost is approximately 30 million won, which is a significant advantage over the previous one.
고부가가치선 선실의 소음 저감용 복합패널의 차음특성 해석
권현웅(Hyun-Wung Kwon),홍석윤(Suk-Youn Hong),길현권(Hyun-Gwon Kil),김화묵(Hwa-Muk Kim),송지훈(Jee-Hun Song) 한국해양공학회 2012 韓國海洋工學會誌 Vol.26 No.3
Recently, as the importance of the interior noise in a ship cabin has risen, ship builders have becomeconcerned about the use of noise reduction panels to reduce cabin noise. The results of previous researches have been based on analytical and experimental methods using simple sandwich panels. However, panel structures are becoming more complex to improve the transmission loss. Thus, researches that analyze the transmission loss of a panel are reaching the limit of study. This paper reports on research that was performed to determine the sound transmission characteristics of multi-complex panels applicable to high value-added vessels. It presents comparisons between analytical methods and experimental results by using a mini-reverberant chamber with components of sound attenuation panels, including the core and surface materials. The sound transmission loss of multi-complex panels are also analyzed in terms of the influences of the inside perforate plates and air gap thickness on the attenuation. Finally, the multi-complex panel with the highest noise attenuation is proposed based on the analysis results and experimental results in mini-reverberant chamber, which wereverified using a real-size reverberant chamber.