• Journal of the Society of Naval Architects of Korea
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• v.48 no.3
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• pp.267-274
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• 2011

This paper presents the results of prediction of maneuverability of KCS about 4 degree of freedom(DOF) including roll motion. The prediction is carried out by CPMC captive model test. The CPMC(Computerized Planar Motion Carriage) with captive model test equipment including roll moment gage is installed at Ocean Engineering Tank of MOERI. KCS is the container ship open to the world by MOERI. To predict the 4 DOF maneuverability of a ship some tests with roll angle are conducted. And the prediction results of maneuverability by simulation are compared with the results of free running model test. The simulation results agree well with those of free running model tests.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.5
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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.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.6
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• pp.553-561
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• 2009

This paper presents the results of prediction of maneuverability of KCS by CPMC captive model test. The CPMC(Computerized Planar Motion Carriage) with captive model test equipment is installed at Ocean Engineering Tank of MOERI. KCS is the container ship which was open to the world by MOERI. And the test results for the prediction of maneuverability were presented by NMRI in Japan. The research results about the maneuverability of KCS were presented at SIMMAN 2008 Workshop in Denmark. The results of test and simulation of this paper are compared with the results of simulation by MOERI using test results of NMRI and simulation results by NMRI.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.3
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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.

• Journal of Navigation and Port Research
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• v.44 no.2
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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.

• Journal of Ocean Engineering and Technology
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• v.31 no.5
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• pp.340-345
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• 2017

It is important to predict the hydrodynamic maneuvering derivatives, which consist of the forces and moment acting on a hull during a maneuvering motion, when estimating the maneuverability of a ship. The estimation of the maneuverability of a ship with a change in the stern hull form is often performed at the initial design stage. In this situation, a method that can reflect the change in the hull form is necessary in the prediction of the maneuverability of the ship. In particular, the linear hydrodynamics maneuvering derivatives affect the yaw checking motion as the key factors. In the present study, static drift calculations were performed using Computational Fluid Dynamics (CFD) based on Reynolds Average Navier-Stokes (RANS) for a 40-segment hull. A prediction method for the linear hydrodynamic maneuvering derivatives was proposed using the slender body theory from the distribution of the lateral force acting on each segment of the hull. Moreover, the results of a comparison study to the model experiment for KVLCC1 performed by KRISO are presented in order to verify the accuracy of the static drift calculation. Finally, the linear hydrodynamic maneuvering derivatives obtained from both the model test and calculation are compared and presented to verity the usefulness of the method proposed in this study.

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.25-31
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• 2002

A system identification method is introduced to increase the prediction accuracy of a ship's maneuverability in PMM test, analysis. To improve the accuracy of linear hydrodynamic coefficients, the analysis techniques of pure sway and yaw tests are developed, and confirmed. In the analysis of sway tests, accuracy to linear hydrodynamic coefficients depends on the frequency of sway motion. To obtain nonlinear hydrodynamic coefficients for large drift angles, a combined yaw test is introduced. Using this system identification method, runs of PMM test can be reduced while retaining sufficient accuracy, compared to the Fourier integration method. Through the comparisons with sea trial results and the Fourier integration method, the accuracy and efficiency of the newly proposed system identification method, based on least square method, has been validated.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.2 s.146
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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.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.2 s.146
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• pp.171-176
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• 2006

To improve ship's maneuverability high lift rudders like as Schilling rudder, flap rudder etc. were used. To predict the maneuverability of a ship with flap rudder HPMM tests are carried out. To analyze the test results modular model is used. To use modular model the forces of flap rudder must be measured separately from the hull forces. The flap rudder is made as independent system from the hull. To investigate the simulation results of modular model the tests results are analyzed by whole ship model, and simulated. The compared results of simulation show a good agreement except turning test. The reason is the different analysis result of flap rudder drag forces. From the present study it is possible to analyze HPMM tests of a ship with flap rudder by modular model.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.4
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• pp.275-285
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• 2017

In order to predict the sailing performance of a LNGC during actual operation, it is necessary to consider not only the information about resistance, maneuverability etc. but also the information such as sea route and sailing scenario etc., comprehensively. In this paper, we propose a new approach to conduct the sailing simulation of a LNGC without full scale measurement data. Latitude, longitude, sea route, speed over ground, time in UTC obtained from AIS data are substituted for the measured data. By combining the model test results, design information, and AIS data, prediction of sailing performance is conducted from the coast of southern Taiwan to the coast of Madagascar. The simulation is verified by comparing the calculated time histories of RPM and power with those of measured RPM and power.