• Journal of Ocean Engineering and Technology
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• v.25 no.2
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• pp.15-20
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• 2011

This study aimed at validating the adopted numerical methods to solve two-phase flow around a two-dimensional (2D) rectangular floating structure in regular waves. A structure with a draft equal to one half of its height was hinged at the center of gravity and free to roll with waves that had the same period as the natural roll period of a rectangular barge. In order to simulate the 2D incompressible viscous two-phase flow in a wave tank with the rectangular barge, the present study used the volume of fluid (VOF) method based on the finite volume method with a standard turbulence model. In addition, the sliding mesh technique was used to handle the motion of the rectangular barge induced by the fluid-structure interaction. Consequently, the present results for the flow field and roll motion of the structure had good agreement with those of the relevant previous experiment.

• Journal of Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.26-34
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• 1999

Two types of barge, container and tanker vessels, are designed with specific dimensions for canal-coastal shipping in Kyung-In canal and Yellow Sea region. The principal dimensions of barges are determined by considering the environment of Kyung-In canal and Yellow Sea. The selection of structure type and structure type and strength confirmation is conducted by the technical rules of Korean Register of Shipping. For the structural analysis of designed barges, the semi-direct stuctural analysis is carried out with using MSC NASTRAN software. Applying identical dimensions to both vessels, the standardization of structural design and analysis procedure are introduced.

• Journal of Ocean Engineering and Technology
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• v.25 no.5
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• pp.27-32
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• 2011

Recently, a ship-shaped barge has been developed to improve the resistance performance, as well as course-keeping capability. However, the stern of the barge is still similar to a box shape, and the vortex generated at the side of the barge creates drag and yaw instability. In order to solve this problem, stern skegs are normally used. The present paper deals with the correlation between the size of the stern skegs and the barge dimensions and hull coefficient. A stern skeg was designed to prevent yaw instability and minimize any additional resistance. The resistance test and course keeping test were performed in the towing tank at Pusan National University. To determine the correlation parameters between the designed stern skeg size and barge dimensions, a parametric study was also performed. Based on the experimental data from five barges, the optimum skeg dimensions were successfully derived. It is expected that the validation of the present study will be carried out by further experiments and computational comparisons in the near future.

• Journal of the Society of Naval Architects of Korea
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• v.34 no.4
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• pp.1-11
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• 1997

When a barge is towed by a tug boat using a tow line, the barge is frequently subject to a large sway motion induced from its inherent yaw motions. This large sway motion combined with external forces due to winds and waves may makes the towing to be difficult or even dangerous. It has been reported that in worse situations, barges or tugs are capsized. In addition, the large sway motion of the towed barge gives a menace to the safety of ships navigating nearby. This paper is the results of the experimental investigation into the course stability of an 8,000 DWT barge using a Towing Tank and a Circulating Water Channel. Various skegs are designed and course stability tests for the barge with skegs are conducted in calm water and in irregular waves. It is observed that an effective skeg attached to the barge enables the sway motion to be zero while the sway amplitude of the bare hull is around 10 times its breadth.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.385-392
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• 2017

This research presents the results of a study on the trajectory characteristics of barges with different configurations. A towing experiment was carried out in a water tank with three types of barges in two cases: with and without skegs. The effects of towline length on trajectory were also observed. This study analyzed and compared the length and amplitude of trajectory shapes for each barge in various combinations. It revealed that the trajectory of a barge is influenced not only by skegs but also by the length of the towline. As a result of this work, it can be clearly seen that skegs significantly improve the course stability of a towed barge regardless of differences in bow shape or towline length. Water tank test results also indicated that the length of a towline plays a key role in affecting the trajectory characteristics of a barge-towing system. The length and amplitude of the slewing motion of a barge increased with an increase in the length of the towline connected to the barge. Validation of the present research results should be carried out by further experiments and computational comparisons in the near future.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.7
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• pp.800-806
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• 2016

The maneuverability of a tugboat is affected by the slewing motion of a barge while the tug is navigating with the barge in water. Therefore, it is necessary to reduce the slewing motion of the barge to allow for safe towing work. In this study, a water tank experiment was performed to examine the factors affecting the slewing motion of a barge and improve course stability. The characteristics of slewing motion vary according to bow shape. Three barge models, each with a different bow shape, were selected as experimental subjects. A comprehensive analysis was performed to study the effects of various factors on the slewing motion of a barge such as the presence of a skeg and bridle, towing speed, and the length of the towline. The effect of the location of the skeg varied according to bow-hull form. The slewing motion of the barge decreased as the length of the towline increased, and this decrease was even greater when a bridle was connected to the towline. In addition, the slewing motion decreased significantly as the length of the bridle increased. The slewing angles did not show significant change with respect to towing speed.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.3 s.153
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• pp.267-278
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• 2007

This experimental study investigated on the eddy making effect on the roll motion of a rectangular barge in a two-dimensional wave tank. The structure was used to simulate a simplified rectangular barge in the beam sea condition. The structure with a draft one half of its height was hinged at the center of gravity and free to roll by waves. The rectangular barge was tested with regular waves with a range of wave periods that are shorter, equal to, and longer than its roll natural period. Particle image velocimetry (PIV) was employed to obtain the velocity field in the vicinity of the structure. The coupled interactions between the incident wave and the barge were demonstrated by examining the vortical flow fields to elucidate the eddy making effect during the roll motion. For incoming wave with a wave period same as the roll natural period, the barge roll motion was reduced by the eddy making damping effect. At the wave period shorter than the roll natural period, the structure roll motion was slightly reduced by the vertical flow around the barge. However, at the wave period longer than the roll natural period, the eddy making effect due to flow separation at structure corners indeed amplifies the roll motion. This indicates that not only can the eddy making effect damp out the roll motion, it can also increase the roll motion.

• Journal of Navigation and Port Research
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• v.42 no.2
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• pp.127-136
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• 2018

The motion response of floating structures is of significant concern in marine engineering. Floating structures can be disturbed by waves, winds, and currents that create undesirable motions of the vessel, therefore causing challenges to its operation. For a floating structure, mooring lines are provided in order to maintain its position; these should also produce a restoring force when the vessel is displaced. Therefore, it is important to investigate the tension of mooring lines and the motion responses of a twin barge when moored to guarantee the safety of the barge during its operation. It is essential to precisely identify the characteristics of the motion responses of a moored barge under different loading conditions. In this study, the motion responses of a moored twin barge were measured in regular waves of seven different wave directions. The experiment was performed with regular waves with different wavelengths and wave directions in order to estimate the twin-barge motions and the tension of the mooring line. In addition, the motion components of roll, pitch, and heave are completely free. In contrast, the surge, sway, and yaw components are fixed. In the succeeding step, a time-domain analysis is carried out in order to obtain the responses of the structure when moored. As a result, the Response Amplitude Operator (RAO) motion value was estimated for different wave directions. The results of the experiment show that the motion components of the twin barge have a significant effect on the tension of the mooring lines.

• Journal of Navigation and Port Research
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• v.34 no.6
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• pp.417-422
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• 2010

In this study, the resistance performances of barge are analyzed by model tests and computation using CFD to investigate the flow characteristics around a barge in still water. The model tests are carried out in infinite depth in Inha Technical College Circulation Tank to observe the resistance and the numerical simulations based on VOF(Volume of Fluid) method are performed to analyze the flow around the barge. We have selected two barge models to investigate the flow characteristics according to the different type of barges. The experiments are carried out with the models from 5kts to 10kts(designed speed 7kts) considering the effect of adverse and favorable current. The numerical simulations are performed to analyze the flow and resistance characteristics of barge in the full loaded condition with the target speed and compared with the experimental data to confirm the reliability of the numerical method. The result was that the difference of resistance with 25% occurred at low speed and EHP increased rapidly from 7kts.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.162-163
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• 2018

This study introduces the R&D project of development of the 1st LNG bunkering barge in Korea. The Design and pilot test of Barge-To-Ship 500cbm LNG bunkering barge system for coastal trading LNG-fueled ship is proposed. The following technologies will be developed from the project ; Basic/Detail design and pilot test of LNG Bunkering barge system, Basic/Detail design and pilot test of LNG bunkering process system considering LNG loading/unloading, Basic/Detail design and pilot test of 500cbm LNG tank in type-C, Evaluation of bunkering performance according to conditions (environment, SIMOPs) by numerical simulation, Performance evaluation of bunkering barge, towed barge and Barge-To-Ship motion considering ocean environment load, and scenario in Barge-To-Ship LNG bunkering. This project will contribute expansion to LNG-fueled ship industry and pave the way to establish LNG bunkering hub port.