• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2011년도 춘계학술대회
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• pp.7-9
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• 2011

In December 2002, International Maritime Organization (IMO) has adopted the Resolution MSA.137(76) Standards for the Ship Maneuverability. For applying the standards, we have to estimate and evaluate the Maneuverability of a ship at the design stage in difference of trim and displacement as accurate as possible. In this paper, the effect of loading condition on the ship Maneuverability was investigated through 3 methods : numerical simulation, free running model ship and real ship data.. Firstly, We carried out numerical simulation, free running model ship experiments and real ship experiments at ballast condition, half loaded condition and full loaded condition with difference of trim.. Secondly, by comparing these results of 3 methods, we draw out the trend of ship Maneuverability due to the change of trim and displacement of a ship.

• 수산해양기술연구
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• 제57권3호
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• pp.246-255
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• 2021

Most fishing vessels are less than 100 m in length (LBP), which is not mandatory for the IMO standards for ship maneuverability. Therefore, research on estimating the maneuverability of fishing vessel hull shapes are somewhat lacking compared to that of merchant ship hull shapes, and at the design stage, the numerical simulation method developed for merchant ships are applied without modification to estimate the maneuverability. Since this can cause estimation errors, the authors have derived a modified empirical formula that can improve the accuracy of estimating the maneuverability of fishing vessels in a previous study. In this study, using the modified empirical formula, the IMO maneuverability evaluation items, the turning motion test and Z-test simulations were performed on the fisheries training vessel BAEK-KYUNG and compared with the sea trial test result to verify the validity of the modified empirical formula. In conclusion, the modified empirical formula was able to estimate quantitatively and qualitatively similar to the result of the sea trial test. Such a study on estimating the maneuverability of fishing vessels will be a good indicator for fishing vessel operators and will help them analyze marine accidents.

• 대한조선학회논문집
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• 제46권3호
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• pp.259-267
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• 2009

Recently, ship maneuverability has been very important issue due to accidents of frequent occurrence at sea. IMO standards for ship maneuverability were applied from January 1, 2004. In this study, maneuverability model tests were considered through a 2m-class KVLCC1 in the Ocean Engineering Wide Tank at University of Ulsan(UOU). Circular Motion Test(CMT) was performed to obtain the maneuvering coefficients by using X-Y Carriage. The trajectories simulated using the coefficients are compared with those of PMM test and free running test.

• 대한조선학회논문집
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• 제48권5호
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• pp.465-472
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• 2011

Recently, ultra large scale of ship is being ordered continuously and because of that, the accurate prediction of ship maneuverability in design stage becomes important matter. The model test like PMM test or CFD analysis are representative methods for predicting the maneuverability of ship. In this study, the captive model tests were carried out for predicting maneuverability of MOERI container ship(KCS) which is opened to the public using X-Y Carriage of Ocean Engineering Wide Tank of University of Ulsan. Considering the dimensions of tank, 2m class model ship was used for captive model test. CMT(Circular Motion Test) was performed for obtaining purer hydrodynamic coefficients related to yawing velocity. For getting hydrodynamic coefficients which cannot be obtained using CMT, PMM test(Planar Motion Mechanism test) were also performed. The maneuverability prediction results by simulation are compared with those of other research institutes.

• 수산해양기술연구
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• 제56권4호
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• pp.374-383
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• 2020

At ship design stage, the maneuverability is generally estimated based on the empirical formula or the computational fluid dynamic (CFD), which is one of the numerical simulation methods. Using the hydrodynamic derivatives derived through these methods can quantitatively estimate the maneuverability of target vessels and evaluate indirect maneuverability. Nevertheless, research on estimating maneuverability is insufficient for ships not subject to IMO maneuverability standard, especially fishing vessels, and even at the design stage, the empirical formula developed for merchant ships is applied without modification. An estimation error may occur due to the empirical formula derived from the regression analysis results of a model test if the empirical formula developed for merchant ships with different hull shapes is applied to fishing vessels without any modification. In this study, the modified empirical formula that can more accurately estimate the fishing vessel's maneuverability was derived by including the hull shape parameter of target fishing trawlers in the regression analysis process that derives Kijima et al. (1990) formula. As a result, the modified empirical formula showed an average estimation error of 6%, and the result improved the average error of 49% of Kijima et al. (1990) formula developed for merchant ships.

• 대한조선학회논문집
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• 제43권2호
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• pp.164-170
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• 2006

To improve ship's maneuverability and carry out special goal POD propulsion system was equipped as propulsion and maneuvering system. To predict the maneuverability of a ship with POD propulsion system HPMM tests and POD open water test are carried out. In this paper modular model with 4 degree of freedom of a ship with twin POD propulsion system is presented. To use modular model the forces of POD propulsion system are measured separately from the hull forces. The measured forces and moments are analyzed by using modular model and whole ship model The simulation results of modular model are compared with those of whole ship model. From the present study it is Possible to analyze HPMM tests of a ship with twin POD propulsion system by modular model.

• 수산해양기술연구
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• 제60권2호
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• pp.179-185
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• 2024

The model ship of this study, the Baek-Kyung fisheries training ship of Pukyong National University, has a length between perpendiculars of 85 meters, making it not subject to the IMO maneuverability standards. However, understanding the maneuvering characteristics of the vessel is essential for safe navigation. In this regard, this study was conducted to analyze the results from the sea trials of the model ship conducted in accordance with the IMO maneuverability standards. The results of the turning tests met the standards well while in the zig-zag tests, the first overshoot angle exceeded the standard in the 10°/10° test; however, such results met with a difference of 1.8° in the 20°/20° test. Additionally, using the course-stability discrimination formula, the calculated value was -0.0051, indicating unstable course-stability. The results of the stopping tests met the standards well. It is hoped that the analyzed maneuvering characteristics of the model ship from the study results will contribute to the safety of ship navigation.

• 해양환경안전학회지
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• 제28권5호
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• pp.800-808
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• 2022

국제해사기구에서는 해상에서의 선박의 충돌방지와 그로 인한 해양환경의 보호를 목적으로 1993년 11월 선박조종성능에 대한 잠정지침을 채택한 이후, 축적된 데이터를 바탕으로 2002년 12월 선박조종성능에 대한 확정된 지침을 채택하였다. 하지만 채택된 지침은 만재상태, 등흘수 및 선박의 최대 출력(MCR)의 85 %에 해당되는 선속의 최소 90 % 이상에서의 지침으로, 동 지침은 항해사에게 필요한 실 항해조건에서의 조종성능 정보를 제공하는 데 한계가 있다. 따라서 본 연구에서는 항해사, 선장 및 선박조종에 대한 식견을 갖추고 있는 전문가를 대상으로 빈도분석과 AHP 분석기법을 실시하여 현 지침에 대한 활용도 및 실제 선박조종에 필요한 정보가 무엇인지를 식별하였다. 연구결과 선박을 운항하는 항해사에게 필요한 조종성능 정보는 5~10°의 소각도에서의 선회권 정보, 항해속력(Sea speed)이 아닌 조종속력(Maneuvering speed)에서의 z-test 정보라는 것을 확인하였고, 속도제어 관련하여서는 항해속력 및 만재상태에서의 정지성능에 대한 정보보다 감속타력, 가속타력 등에 대한 정보가 더 필요하다는 것을 확인하였다. 도출된 결과는 선박을 조종하는 항해사에게 필요한 선박조종성능기준 지침마련에 대한 기초자료로 활용도가 높을 것으로 사료된다.

• 대한조선학회논문집
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• 제51권2호
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• pp.154-161
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• 2014

Naval ships have hull appendages which are more exposed to the outside because of its small block coefficient compared with commercial ships. These exposed hull appendages like skeg, strut and shaft line affect the maneuverability of a ship. The effect of hull appendages has considered at initial design stage to estimate more accurate maneuverability. In this paper, sensitivity analysis is used to analyze the effect on maneuverability by hull appendages. 3 DOF maneuvering equations based on Mathematical Modelling Group (MMG) model are used and propeller & rudder model are modified to reflect the characteristics of twin propeller & twin rudder. Numerical maneuvering simulations (Turning test, Zig-zag test) for benchmark naval vessel, David Taylor Model Basin (DTMB) 5415 are performed. In every simulation, it is calculated that stability indices and maneuverability characteristics (Tactical Dia., Advance, 1st Overshoot, Time of complete cycle) with respect to the parameters (area times lift coefficient slope, attachment location) of hull appendages. As a result, two regression formulas are established. One is the relation of maneuverability characteristics and stability indices and the other is the relation of stability indices and hull appendages.

• 한국항해항만학회지
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• 제44권2호
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• pp.98-109
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• 2020

In recent years, there have been concerted efforts toward predicting ship maneuvering in shallow water since the majority of ship's accidents near harbors commonly occur in shallow and restricted waters. Enhancement of ship maneuverability at the design stage is crucial in ensuring that a ship navigates safely. However, though challenging, establishing the mathematical model of ship maneuvering motion is recognized as crucial toward accurately predicting the assessment of maneuverability. This paper focused on a study on sensitivity analysis of the hydrodynamic coefficients on the maneuverability prediction of KVLCC2 in shallow waters. Hydrodynamic coefficients at different water depths were estimated from the experimental results conducted in the square tank at Changwon National University (CWNU). The simulation of standard maneuvering of KVLLC2 in shallow waters was compared with the results of the Free Running Model Test (FRMT) in shallow waters from other institutes. Additionally the sensitivity analysis of all hydrodynamic coefficients was conducted by deviating each hydrodynamic derivative from the experimental results. The standard maneuvering parameters including turning tests and zig-zag maneuvers were conducted at different water depths and their effects on the standard maneuvering parameters were assessed to understand the importance of different derivatives in ship maneuvering in shallow waters.