• 항공우주시스템공학회지
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• 제8권3호
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• pp.14-19
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• 2014

When a helicopter lands on a ship deck in high sea states, one of main difficulties is the ship motion by sea wave, In case of a manned helicopter, a pilot lands a helicopter on the deck during quiescent period of ship motion, which is perceived from different visual cues around landing spot. The capability to predict this quiescent period is very important especially for shipboard recovery of VTOL UAV in harsh environments. This paper describes how to predict heave motion of a ship for shipboard landing of a VTOL UAV. For simulation, ship motion by sea wave was generated using a 4,000 ton class US destroyer model. Heave motion of ship deck was predicted by applying auto-regression method to generated time series data of ship motion.

• 대한조선학회논문집
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• 제29권1호
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• pp.71-80
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• 1992

국제수조회의(ITTC) 내항성분과에서 회귀현상(rare event)레 대한 시험기법 확립 및 계측기간 결정을 목적으로 19차 ITTC 내항성분과의 공동사업으로 갑판침수 계측시험을 수행한 바 있다. 본 논문에는 공동연구에 참여한 수조시험연구회(KTTC)의 두 회원인 해사기술연구소(KRISO)와 현대선박해양연구소(HMRI)의 실험방법 및 결과를 비교 검토하였다. 선수상대운동과 갑판침수 사이의 상관관계 및 Poisson process에 근거한 계측시간의 추정에 촛점을 두어 결과를 고찰하였다. 동일한 특성을 갖는 입사파에 대해 계측된 갑판침수 빈도수는 두 기관 모두 계측시마다 큰 차이를 보였으며 이는 일반적인 선체운동 계측 보다 더 많은 계측시간이 필요한 것을 의미한다. 선수상대운동과 갑판침수사이의 상관관계는 선수형상, 선속 및 해상상태에 따라 달라지며 본 공동연구의 실험 조건하에서는 (유의파고 7.88m, 선속 22.15노트) 둘 사이의 상관관계가 매우 높은 것으로 나타났다. 또한 갑판침수 현상의 통계적 특성은 Poisson process로 해석될 수 있음을 보였다.

• 수산해양교육연구
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• 제29권1호
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• pp.286-296
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• 2017

This paper conducted a simulation to research the motion of a vessel, which had the flooding accident in the Bering Sea in 2014, thereby being flooded and un-steerable. As the wind condition was very harsh, the vessel was modeled as 3D including large upper deck structures and the Fujiwara's method was used for an estimation of the effect of wind forces and moments acting on ship. In the case of wave influence, AQWA-Drift that enables considering the effects of drift force and AQWA-Naut that enables considering the effects of green water were mainly used. Basically, loading and flooding condition were equal to the accident condition but half-drained condition was also used to consider drain ability. Furthermore, both 6 DOF and 5 DOF option that Yaw motion is fixed, were utilized to compare the steerable and un-steerable condition. As a result, the author found out that what roll angle triggers green water, how often it happens, and how the vessel moves on the stormy weather condition.