• 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.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.70-75
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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.

• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.292-305
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• 2021

The present study concerns uncertainty assessment of powering prediction from towing tank model tests, suggested by the International Towing Tank Conference (ITTC). The systematic uncertainty of towing tank tests was estimated by allowance of test setup and measurement accuracy of ITTC. The random uncertainty was varied from 0 to 8% of the measurement. Randomly generated inputs of test conditions and measurement data sets under systematic and random uncertainty are used to statistically analyze resistance and propulsive performance parameters at the full scale. The error propagation through an extrapolation procedure is investigated in terms of the sensitivity and coefficient of determination. By the uncertainty assessment, it is found that the uncertainty of resultant powering prediction was smaller than the test uncertainty.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.5 no.1
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• pp.14-20
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• 1969

A scale model net test of the operation of a small two-boat midwater trawl net was performed in the circulating water tank at Pusan Fisheries College. The 1/32 scale model net was constructed after the modelling law of M. Tauti. This type of net is used in Europe for catching sprat like Hering. The net used was 1/32 the actual size. This scale was chosen with consideration for the water tank size. In this experiment, the transfomation of the net shape was observed especially inregard to variations in the height and breadth of the net mouth. These dimensions were varied by changing the breadth of the towing line and the connenting spread.

• Journal of Ship and Ocean Technology
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• v.9 no.2
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• pp.1-10
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• 2005

A light-weight cantilever type towing carriage was devised and installed in the towing tank at Seoul National University. Wireless measurement devices were also provided for appropriate data acquisition during high-speed towing tests. With the new carriage system, a series of model tests were performed to investigate the hydrodynamic characteristics of the racing boat in the towing tank and the resistance test results had sufficient accuracy so that they could be used in the development of a high speed planning hull.

• Journal of the Society of Naval Architects of Korea
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• v.49 no.4
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• pp.327-332
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• 2012

International Towing Tank Conference (ITTC) recommended verifying a ship's ability to move transversely at zero forward speed without altering heading by a crabbing test. In sea trial, all available propellers/rudders/thrusters should be used to find the maximum possible transverse speed. For estimating crabbing ability in the design stage, tests to estimate possible swaying force and yawing moment range using all available propellers/rudders/thrusters are conducted. By butterfly diagram, which compares possible swaying force and yawing moment range with external swaying force and yawing moment by wind, a ship's crabbing ability can be estimated. In this study, model tests of a cruise vessel equipped with bow thrusters and POD system were conducted to find out her crabbing ability in the design stage. To mimic quay condition, a model quay-wall was set in the towing tank.

• Journal of Ocean Engineering and Technology
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• v.28 no.1
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• pp.1-5
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• 2014

Chosun University, in cooperation with SPP shipyard, has developed an energy saving device based on a new concept: "Crown Duct." Crown Duct is composed of a semi-duct with short struts inside and outside the duct. Theoretical calculations for two different designs were carried out using the CFD code "Ship Flow." The design selected from these two different forms by the CFD code analysis was tested in a towing tank at SSPA. The results showed about 4% efficiency gain under a full-load condition and about 7% gain under a ballast condition in the towing tank test.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.876-893
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• 2014

The resistance performance of an icebreaking cargo vessel according to the variation of waterline angles is investigated numerically and experimentally. A recently developed Finite Element (FE) model is used in our analysis. A resistance test with synthetic ice is performed in the towing tank at Pusan National University (PNU) to compare and validate the computed results. We demonstrate good agreement between the experimental and numerical results. Shipice interaction loads are numerically calculated based on the Fluid Structure Interaction (FSI) method in the commercial FE package LS-DYNA. Test results from model testing with synthetic ice at the PNU towing tank are used to compare and validate the numerical simulations. For each waterline angle, numerical and experimental comparisons were made for three concentrations (90%, 80%, and 60%) of pack ice. Ice was modeled as a rigid body, but the ice density was the same as that used in the experiments. A comparative study according to the variation of stem angles is expected to be conducted in the near future.

• International Journal of Naval Architecture and Ocean Engineering
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• v.5 no.3
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• pp.404-413
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• 2013

In the present study, a towed underwater particle image velocimetry (PIV) system was validated in uniform flow and used to investigate the free-surface effects on the turbulent wake of a simple surface-piercing body. The selected test model was a cylindrical geometry formed by extruding the Wigley hull's waterplane shape in the vertical direction. Due to the constraints of the two-dimensional (2D) PIV system used for the present study, the velocity field measurements were done separately for the vertical and horizontal planes. Using the measured data at several different locations, it was possible to identify the free-surface effects on the turbulent wake in terms of the mean velocity components and turbulence quantities. In order to provide an accuracy level of the data, uncertainty assessment was done following the International Towing Tank Conference standard procedure.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.1
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• pp.8-15
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• 2014

In this study, flow characteristics around the hull form of KLNG are investigated by numerical simulations. The numerical simulations of the turbulent flows with the free surface around KLNG have been carried out at Froude number 0.1964 using the FLUENT 6.3 solver with Reynolds stress turbulence model. Several GEOSIM models are adopted to consider the scale effect attendant on Reynolds number. Furthermore, a full scale ship is calculated and the result is compared with the numerical results of GEOSIM models. The calculated results of GEOSIM models and the full scale ship are compared with the experiment data of MOERI towing tank test and Inha university towing tank test. Moreover, wake distribution on the propeller plane of the full scale ship is estimated using the numerical results of GEOSIM models. The prediction result is directly compared with the simulation result in full scale.