• Proceedings of KOSOMES biannual meeting
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• 2001.05a
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• pp.149-166
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• 2001

작은 메타센터높이를 가진 선박이나 고속선 등의 조종성능은 횡동요(roll) 운동이 미치는 영 향에 대해서 고려되어야 할 것이다. 이러한 조종성능의 추정은 surge-sway-yaw 조종운동 방정식에 횡동요 운동을 추가함으로써 가능하게 된다. 본 연구에서는 선박의 4-자유도 운동에 대한 조종성능 추정기법에 대해서 논하였다. 구체적으로 surge-sway-yaw 조종운동방정식에 추가되는 roll 운동항에 대한 새로운 모델을 제안하였으며, 다른 추정결과값과 비교 ·검토하였다. 그 결과, 새로운 모델을 운동방정식에 추가함으로써 만족스러운 조종성능을 추정할 수 있었다.

• Journal of Navigation and Port Research
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• v.27 no.5
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• pp.451-458
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• 2003

A ship with small metacentric height or high speed vessel performs relatively large roll angles in her manoeuvring motion. Roll coupling effect should be taken into consideration for accurate prediction of manoeuvring motion of such a ship. This paper proposes a new mathematical model of ship manoeuvring motion taking coupling effect of roll into consideration. Some kinds of manoeuvring motion are simulated by computer, based upon the proposed model. The simualted results by proposed model here are compared with those by existing model. The proposed model is found to be practical and useful for prediction of manoeuvring motion with roll effect.

• Journal of the Society of Naval Architects of Korea
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• v.33 no.4
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• pp.60-65
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• 1996

Mathematical model of maneuvering motion for a single-screw single-rudder ship established and versatile applications to the special situations of maneuvering are attempted. While, the mathematical model for twin-screw twin-rudder ship is not presented so much, because that type of ship is not popular. Lee et al. have examined the characteristics of such ship by captive model tests in 1988. This paper treats new mathematical models for propeller effective wake ($1-w_p$) and effective neutral rudder angle ${\delta}_R$ in the case of twin-screw twin-rudder ship. And some maneuvering motions are calculated with proposed models and compared with exact simulations.

• Journal of Navigation and Port Research
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• v.34 no.8
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• pp.629-634
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• 2010

Mathematical model of maneuvering motion for a Mobile Harbor is established and versatile applications to the special situations of maneuvering are attempted. The Mobile Harbor in this research has twin Azipod thruster and twin bow thruster. In order to predict the maneuverability of Mobile Harbor, a mathematical model was developed on the basis of MMG model, and some model test results were adopted for the simulation of Mobile Harbor. As a result, the turning motions of the Mobile Harbor were successfully calculated. and the optimal berthing system was completed.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.4
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• pp.82-98
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• 1994

A mathematical model for the hydrodynamic forces acting on the ship manoeuvring in waves is formulated and a numerical method for the problem is developed. The motion of a ship, which manoeuvres in waves, may be thought to have two components; one is a high frequency component due to encounter waves, and the other is a low frequency component due to manoeuvring motion. So the method of two time scale expansion is used to divide linear boundary value problem. For the effects of waves on the manoeuvring motion of a ship, only the second order drift forces are considered. The integral equation for the velocity potential is solved by 3 dimensional panel method and hydrodynamic forces are calculated by direct integral method.

• Proceedings of KOSOMES biannual meeting
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• 2001.05a
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• pp.53-77
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• 2001

선박의 항행안전의 문제가 중요시됨에 따라 선박조종시뮬레이터에 의한 안전성 검토의 필요성이 크게 인식되고 있다. 또한 조종성능을 향상시킬 목적으로 다양한 선종이 출현하고 있고, 이에 따라 선박조종시뮬레이터의 개발에 있어서 선박의 데이터베이스는 필수적이라고 할 수 있다. 따라서 선종에 따른 수학모델을 각각 선박조종시뮬레이터에 적용시킴으로써 다양성이라는 가상현실의 잇점을 한층 부각시킬 수 있다. 본 연구에서는 우수한 추진성능을 목적으로 한 2축2타선박을 대상으로 조종운동 수학모델을 정식화하였다. 구체적으로 항만내에서의 저속시 조종운동을 구현할 수 있는 수학모델에 대해서 검토하였으며, 선체·프로펠러·타의 상호간섭에 대해서도 고려하였다. 또한, 수치시뮬레이션을 수행함으로써 2축2타선박의 기본적인 조종성능을 확인할 수 있었다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.1-3
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• 2018

국제해사기구(IMO)의 황천 중 조종성능 유지를 위한 최소추진마력 기준 제정과 국제수조협회(ITTC)의 파도 중 조종성능 추정에 대한 관심이 증가하면서 파도 중 조종성능 추정기술에 대한 연구가 많이 수행되고 있다. 본 연구에서는 파도 중 조종성능을 추정하는 기법중 하나인 시뮬레이션 기법 중에서 조종운동만을 시뮬레이션하는 간이 시뮬레이션을 수행하였고, 시뮬레이션 결과를 검증하기 위하여 자유 항주시험결과가 존재하는 S-175 컨테이너선에 대한 시뮬레이션을 수행하여 비교하였다.

• Journal of Navigation and Port Research
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• v.32 no.8
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• pp.603-609
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• 2008

Manta-type Unmanned Undersea Test Vehicle(MUUTV) is based on the same design concept as Unmanned Undersea Vehicle called Manta Test Vehicle(MTV), which was originally built and operated by the Naval Undersea Warfare Center(Lisiewicz et al., 2000, Sirmalis et al. 2001). The authors carried out the sensitivity analysis of the response of manoeuvring motion of MUUTV to changes in hydrodynamic derivatives, In order to calculate the sensitivity indices of hydrodynamic derivatives on MUUTV, the method by Sen(2000) was adopted Basically the dynamic mathematical model with six degrees of freedom by Feldman(1979) is used but a little revised, refered to Sohn et al.(2006) and some experiment in circulating water channel. Through the present research, some hydrodynamic derivatives of significance are found out, and also the numerical simulation using simplified mathematical model based on result of sensitivity analysis is ascertained to be enough for prediction of manoeuvring characteristics of MUUTV.

• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.3
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• pp.1-16
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• 2001

In view of the fact that marine casualties have more often occurred recently, there is a need for ship-handling simulator as a useful tool for maritime training, safety assessment and so on. Moreover various kinds of hull forms have appeared for the purpose of improving ship manoeuvrality. Therefore ship-handling simulator is in need of a database for various ships, and it can make diverse maneuvering simulations possible to apply respective mathematical model to ship-handling simulator. In this paper, we adopted twin-screw and twin-rudder ship and discussed mathematical model of maneuvering motions for her. It was discussed from the viewpoint of hull damping forces at low advance speed and interaction between hull, propeller and rudder. Using this model, maneuvering motion of twin-screw and twin-propeller ship was simulated numerically and her principal manoeuvrability was examined.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.3
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• pp.90-101
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• 1992

Some practical methods have already been proposed for predicting the characteristics of ship manoeuvring motions at relatively high advance speed. However, these methods can hardly be applied to motions of ships in starting, stoppint, backing and slow steaming conditions, even though such extensive motions are of vital importance from a safety point of view particularly in harbour areas. The method presented here aims at predicting the characteristics of ship manoeuvring at low advance speed, which covers starting, stopping, backing and slow steaming conditions. The force mathematical models at large angles of incidence to the hull as well as under the tilde range of propeller operations are formulated. Simulations of various manoeuvres at low advance speed are carried out for two types of merchant ship, i.e. a LNGC and a VLCC. Comparisons between simulations and corresponding full-scale measurements or free-running model tests provide a first verification of the proposed mathematical models.