• 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 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.

• Bulletin of the Society of Naval Architects of Korea
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• v.30 no.1
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• pp.28-34
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• 1993

William Froude(1810-1879)는 현대 시험수조의 창시자이다. 그는 19세기 영국의 조선공학자로서 비교법칙을 정립하고, 예인식 시험수조를 지어 정확한 모형시험을 처음 수행함으로서 시험수조의 역할을 확립한 사람이다. W.Froude의 생활, 그 당시의 기술현황, 그가 고민하며 찾아 나간 실험 및 해석 기법 그리고 현재 해석법과의 연관등을 찾아 이 소고를 작성하였다.

• 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.33 no.4
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• pp.15-21
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• 1996

Recently speed control system of the towing carriage have been modified by applying a personal computer in the Ship Model Towing Tank of Seoul National University. With this system the carriage speed could be controled precisely in coincidently with a prescribed speed diagram to evaluate the effect of slight towing speed fluctuation caused by some residual current or standing waves which have believed as trivial phenomena in the towing tank. It is found that the slight speed fluctuation of the carriage could lead to serious error in measurement of resistance test of a ship.

• 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 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.

• New & Renewable Energy
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• v.7 no.4
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• pp.42-49
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• 2011

The objective of this paper is to suggest a new method of a wind turbine performance test. The performance test of a wind turbine is generally carried out in a wind tunnel. The test needs not only a high-accuracy measuring system but also durable structure to withstand high speed turbine rotation and wind flow. Therefore, we tried turbine performance test using a towing tank to improve stability and reliability. Because a turbine rotates more slowly and generates more torque in the water than in the wind tunnel under similarity conditions. In this study, we developed turbine performance test systems and verified the turbine test method using a towing tank through comparing results of the wind tunnel and the towing tank test.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.4
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• pp.259-265
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• 2016

The present study aims to design and utilize a model test system of a Caisson in wet towing condition, to assess towing stability of a 9,300 ton class caisson. The suggested towing system was designed to provide regular tension on the towline, whereas the previous model test system towed the model in constant speed. The new model test system was expected to reproduce the towing condition more realistically than the test system with constant speed condition, as the tugboat in actual towing condition tows the towline with constant power. Model tests were conducted in a towing tank with 1/30 scaled model. In the model tests, six-degrees-of-freedom motion of the caisson model and tension on the towline were measured and analyzed. By using the new system, fluctuation of the motion of model and tension on the towline decreased. The variation in the draft and initial trim was applied in the model tests. In the initial trim condition, the motion and towing force decreased.

• Journal of Navigation and Port Research
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• v.31 no.10
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• pp.813-818
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• 2007

There are the C.W.C and Towing Tank to the model-test equipments of the boat. A model testing of the high speed boat have a difficult in the performance verification because of very a small the scale-ratio of the ship-model and restricted by flow-velocity of the C.W.C and X-carriage velocity of the T.T. In general, the stepped hull boat is a high of fuel-efficiency because of the resistance reduction by a small wetted surface-area in correspond without stepped-hull boat. But It have a tendency to be bad the rolling performance by reduced stern wetted-area In this paper, the high speed stepped planning-boats with & without attached a stern body were performed to compare the effect of resistance and rolling performance by using sea model-test method.