• Korean Journal of Computational Design and Engineering
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• v.8 no.3
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• pp.141-149
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• 2003

The ship STEP is an international standard for the computer-interpretable representation of ship product information and for the exchange of ship product model data. The ship STEP consists of several APs(Application Protocol), such as AP215(ship arrangement), AP216(ship moulded form), AP218(ship structures), AP226(ship mechanical systems), and AP234(operating logs, records, message). The STEP AP216(ISO 10303) are an application protocol for the exchange of ship arrangement and ship moulded forms. The AP216 specifies the geometric shape and the hydrostatic properties of the ship moulded form. This paper introduces the state-of-the-art of ship STEP AP216 and develops the test case for the validation of data structure of AP216.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.6
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• pp.776-781
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• 2010

In the ship-handling simulator, it is important for a ship manoeuvring model to represent the dynamic characteristic of a ship and to be simple for reducing calculation time. Especially, even if principal dimensions of a ship are given in initial design stage, or manoeuvring test data are only given by model or real ship's trials, simulations are often needed to check the manoeuvrability of a ship. In this paper, a simple manoeuvring model based on turning test data of a ship is mathematically developed. And the simulation results are verified by comparing with turning test results of a real ship.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1865-1871
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• 2015

Ship's trim is the one of the most important factor for safety at the sea. Turning circle test and Z-test were carried out to find the effect of ship's trim and draft changes. The results are as follows. 1. If the ship's draft and trim became large, turning circle would be wide. 2. If the ship's draft and trim became large, ship's drift angle would be small. Small drift angle made wide turning circle. 3. Trim by the head made slow ship's final speed when turning circle test. 4. By Z-test, the deeper draft and trim by the stern made small OSA. Small OSA means strong ship's stability. 5. Totally 2nd OSA is smaller than 1st OSA on Z-test. 6. There were small differences of 2nd OSA in trim by the stern, but there were large OSA in trim by the head. 7. The larger trim by the stern, the smaller OSW. The small OSW means better ship's stability and maneuverability.

• Journal of Navigation and Port Research
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• v.33 no.9
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• pp.603-608
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• 2009

In this paper, a 3m-class free running model ship will be introduced with its manoeuvring performance experiments. The results of turning circle test and zig-zag test will be explained. The developed system are equipped with GPS, main control computer, wireless LAN, IMU (Inertial Measurement Unit), self-propulsion propeller and driving rudder. Its motion can be controlled by RC (Radio Control) and wireless LAN from land based center. Automatic navigation is also available by pre-programmed algorithm. The trajectory of navigation can be acquired by GPS and it provides us with important data for ship's motion control experiments. The results of manoeuvring performance experiment have shown that the developed free running model ship can be used to verify the test of turning circle and zig-zag. For next step, other experimental researches such as ship collision avoidance system and automatic berthing can be considered in the future.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.61-70
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• 2015

In an attempt to improve the maneuvering character of hull form renovated tuna purse seiner. A renovation was carried out on the 3 tuna purse seiner fishing vessel. To grasp the progress of maneuvering and resistance on ship B (730 ton class), new bulbous bow was only attached. The ship A (740 ton class) and C (600 ton class) were modified for new bulbous bow, enlarged slipway and rudder. And then the zigzag and the turning test were carried out. According to the turning test, the advance and the tactical diameter were improved very much for the modified ship. The sea trial was carried out for the original and modified ship A. It is showed that the results of sea trial corresponded with that of the tank test on the whole. In the result of the zigzag test on ship B, the turning ability was improved very much, but the yaw checking ability was deteriorated in just some degree. In the result of the zigzag test on ship C, the turning ability and yaw checking ability were remarkably improved. Ship C was greatly improved among the three ships for the maneuvering character of modified hull form.

• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.77-83
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• 2009

In this study, we conducted resistance and propulsion performance test of ship composed of the Resistance Test, Propeller Open Water Test and Self Propulsion Test using the CFD(Computational Fluid Dynamics). We used commercial RANS(Reynolds Averaged Navier Stokes equation) solver, as a calculating tool. The unstructured grids were used in a bow and stern of ship, having complex shape, for a convenience of generating grids, and the structured grids were adopted in a central hull and rest of hull having a relatively simple shape which is called hybrid grid method. In addition, The sliding mesh method was adopted to rotate a propeller directly in the Propeller Open Water and Self Propulsion Test. The Resistance Test and Self Propulsion Test were calculated using Volume of Fluid (VOF) model and considering a free surface. And all The three cases were applied realizable k-epsilon model as the turbulence model. The results of calculations were verified for the suitability of calculations by comparing MOERI's EFD results.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.6
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• pp.450-459
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• 2023

According to Korea Maritime Safety Tribunal, there have been 14,100 maritime accidents from 2017 to 2021. Among those accidents, ship collision accidents have been up to 1,275 cases. But in the accidents relating to small ships like a fishing vessel, analyzing the causes of the accidents would depend on statements of the persons related because there is often no navigational data. But those statements can be incorrect and give rise to disagreements between them so that it causes conflicts with each other during the trial. So a replay system of ship collision accident (RESCA) has been developed in order to reproduce the ship collision accident by using AIS, V-PASS or radar data. But the reproduced trajectory of ship collision accident is needed to be verified because it can be unreasonable physically. So a method to verify the reproduced trajectory and collect the physical data on ship collision accident is newly designed by using free running test. In the RESCA, the accident is reproduced using the navigational data from the trajectory for a ship and measured from free running model test for the other ship at the same time. Through free running test, the behavior of the model ship is transformed from model scale into real scale. In order to check into the accuracy of the new method, free running model tests by using RESCA are carried out on the actual ship collision accidents.

• Journal of Ship and Ocean Technology
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• v.9 no.3
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• pp.23-32
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• 2005

Ship STEP(Standard for the Exchange of Product Model Data) which is composed of AP 215 (Ship Arrangement), AP 216(Ship Hull Form), AP 218 (Ship Structure), has been developed more than last 10 years and it is now at the stage just before IS(International Standard). It is expected that ship STEP would be used for the seamless data exchange among various CAD/CAM/CAE systems of shipbuilding process. In this paper the huge and complicated data structure of ship STEP is briefly reviewed at the level of ARM(Application Reference Model) and some abstract test cases which will be included as part of the standards are introduced. Basically ship STEP has common data model to be used without losing compatibility among those three different ship AP's, and it is defined as the modeling framework. Typical cases of data exchange during shipbuilding process, such as hull form data exchange between design office and model basin, midship structure data between shipbuilding yard and classification society are reviewed and STEP physical data are generated using commercial geometric modeling kernel. Test cases of ship arrangement at initial design stage and hydrodynamic data of crude oil carrier are also included.

• Journal of the Korea Institute of Military Science and Technology
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• v.25 no.3
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• pp.259-266
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• 2022

This study aims to introduce missile live-fire during the ship operational test and evaluation(T&E) as a means of verifying the integrated combat capability(ICC) of various systems installed on naval ships. The research method identified domestic and foreign T&E systems and cases, and reports related to ICC, which were written during the ship's design stage. As a result of research, Republic of Korea is not conducting the missile live-fire at the ship T&E stage due to the lack of relevant systems, while the U.S. is conducting it based on the mission-based T&E and the end-to-end test system. As a way to improve within the current domestic ship acquisition systems, the reaction time analysis, a quantitative analysis result of ICC calculated at the ship basic design stage, was proposed to be verified by missile live-fire during ship operational T&E.

• Journal of Navigation and Port Research
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• v.46 no.2
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• pp.73-81
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• 2022

Currently, shipping by sea is becoming common because of the low price and the safety of goods. The ship is designed as a larger vessel to meet the need of this development. In the design stage, the investigation of hydrodynamic forces acting on the ship hull is very important in predicting the ship's maneuverability. Given that the ship docks at various ports for loading or discharging goods, the ship usually operates in various loading conditions, depending on the site condition and other various factors. Hence, it is necessary to investigate the effect of the loading condition on the hydrodynamic forces acting on the ship, to most accurately determine the maneuverability of the ship. In this study, an experiment of Korea Autonomous Surface Ship (KASS) was conducted at the towing tank of Changwon National University to measure the hydrodynamic forces acting on the KASS. The loading condition considered in this experiment is determined based on the draft, which was decreased by 5% for each loading condition. The smallest draft is 85% of the design draft. The static test as Oblique Towing Test (OTT), Circular Motion Test (CMT), Circular Motion Test with Drift (CMTD) is performed in the various loading conditions. First, the hydrodynamic forces in the Oblique Towing test (OTT) are compared with the result of other institutes. Second, the hydrodynamic forces in various drift angle, yaw rate and loading conditions are measured. Finally, the influence of the loading conditions on the hydrodynamic coefficient is discussed.