• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.34-36
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• 2007

현재 모형선을 이용한 선형성능 검증방법에는 크게 2가지 방법이 있다. 첫째는 예인수조에서 예인전차를 이용하여 정수중에 배를 예인시켜 그에 따른 저항을 시험하는 방법이 있고, 둘째는 회류수조에서 배를 고정하여 물을 회전시켜 모형선의 저항을 측정하는 방법이 있다. 이와 같은 방법은 저속 및 대형선박을 검증하기 위해 계발된 방법들로 소형 고속어선 및 고속레저선박의 저항성능 평가를 수행하기 어려운 것이 현실이다. 예인전차의 예인속도와 회류수조 물의 유속이 소형 고속어선 및 고속레저선박의 속력에 미치지 못하기 때문이다. 따라서 고속을 요하는 선박의 저항성능 평가를 위해 새로운 방법 연구가 필요하다. 이에 고속선의 저항성능 시험을 위해 실 해상에서 일반 선박을 이용하여 예인하는 방법을 적용하여 저항시험을 수행하였으며 그에 맞는 시스템을 설계하였다.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.5
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• pp.718-724
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• 2010

This paper studies the differences due to the wall effect in propeller open water(POW) characteristics tested in a towing tank and in a medium size cavitation tunnel(CT). When the advanced velocity of the propeller is defined as the flow velocity measured in the plane of propeller, POW characteristics resulting from CT has a better relationship with them of towing tank. To obtain the wall effect in the propeller plane, numerical computation using the lifting panel theory is performed with and without the wall around a propeller. Then, POW results in CT are corrected based on the wall effect from numerical results. The POW results obtained from this procedure show a better agreement with the experimental results in the towing tank.

• Journal of the Society of Naval Architects of Korea
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• v.36 no.3
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• pp.22-28
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• 1999

Flow measurements on the propeller plane of a 180,000 TDW Bulk Carrier model are carried out using a 3D fiber optics LDV at a towing tank. Mean velocities are successfully obtained. The turbulence characteristics such as Reynolds stresses, skewnesses, and flatnesses, are also investigated. However, those turbulence characteristics may include some errors due to the characteristics of the towing-tank experiments.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.4
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• pp.37-45
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• 2003

Model tests using 2.0m model of the series 60 form( $C_{b}$= 0.6) were carried out in the Circulating Water Channel (CWC) in the Chosun University (CU, Korea) for the purpose of a correlative study with Towing Tank (TT). Resistance, propeller open water, self propulsion and wake survey tests were carried out and the results were extrapolated to the ship scale. These results were compared with the extrapolated ship values based on the model test of 7.0m model in the TT at the Korea Research Institute of Ships and Ocean Engineering (KRISO, Korea). The CWC test results were correlated with the results of the towing tank tests.s.

• Journal of the Society of Naval Architects of Korea
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• v.34 no.2
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• pp.1-10
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• 1997

We have been noticing the unstable phenomena of measured data which may give a bad influence on the prediction of powering performance characteristics. In this paper, ununiformity of water temperature according to the water depth in towing tank, variation of water temperature between summer and winter, effect of turbulence stimulator and double line phenomena in the resistance test are investigated. And circulating the tank water, heating the towing tank, degassing the tank water and improving the turbulence stimulator are proposed as it's solutions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.346-348
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• 2011

해상에서 예부선이 항행시 부선의 선회운동으로 인하여 예부선의 안전운항에 많은 어려움을 겪고 있다. 본 연구에서는 안전한 예항업무를 위하여 실무에서 많이 사용되고 있는 2가지 부선 모델을 대상으로 skeg의 설치 유무 및 skeg의 설치 위치에 의한 부선의 선회운동과 이에 따른 예인장력을 알아보기 위해 정수중에서의 수조실험을 실행하였다. 실험결과 예인삭의 선회각도는 skeg을 설치하지 않았을 때 가장 크게 나타났고, center skeg을 설치했을 때부터 작아지기 시작하여 side skeg을 설치했을 때 예인삭의 선회각도가 급격히 작아지는 것으로 파악되었으며, 이러한 특성은 선수형상에 따라 조금씩 다르게 나타나고 있음을 확인하였다. 또한 예인삭의 선회각도가 커질수록 예인장력이 커지는 것을 알 수 있었다. 따라서 부선에 skeg을 설치하여 운항하는 것이 부선의 선회 운동을 감소시켜 최종적으로 예인장력이 작아지게 하여 안전예항업무에 도움이 될 것으로 판단된다.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.1
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• pp.26-39
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• 2000

This paper presents the influence of Reynolds number on propeller open-water performance at the towing tank and the cavitation tunnel for series propellers(No. of blade=4, $0.3{\leq}A_E/A_O{\leq}0.75,\;0.5{\leq}P/D{\leq}1.1$). It is shown that the Reynolds number recommanded by 15th and 17th ITTC is not large enough to obtain reliable P.O.W. test results and then the suitable test conditions for the both facilities is suggested. The correlation of the propeller open-water characteristics at the cavitation tunnel and the towing tank is described and a correlation factor $\kappa$ is deduced from those test results. The viscous effect of the flow around the propeller shaft on the propeller characteristics is investigated from the velocity measurement by Laser Doppler Velocitimetry(L.D.V.). The measured velocity distribution shows that viscous flow effect is not negligible.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.2
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• pp.1-9
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• 2001

Based on the linear potential theory with the side wall reflection. the directional spectrum waves are numerically simulated by a source distribution method and these together with long-crested irregular waves are also generated at the towing tank of Pusan National University by considering the transfer function of the wave maker obtained from the regular waves. In the numerical simulation, the characteristics of the directional spreading function are investigated by changing the breadth of the wave-maker unit. the width of the towing tank and the wave period. In the experimental generation, the statistical properties and the power spectrums of the long-crested irregular and directional waves are compared along the towing tank length. The directional spreading functions are also investigated at various positions in the tank.

• Journal of Navigation and Port Research
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• v.35 no.6
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• pp.483-488
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• 2011

When a tug-barge navigates in the water, maneuvering ability of a tug is affected by the slewing motion of barge. Therefore it is necessary to decrease the slewing motion of a barge for safe towing work. We chose two different types of barge model and investigated their motion depending on the existence of bridle, towing speed and length of towline. The experiments are performed in the still water using the wire rope for the towline. A longer towline makes the heading angle smaller. The towing speed does not largely affect the turning of barge. Finally, it is noted that the bridle of a towing line decrease the slewing motion of barge more effectively.

• 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.