• Journal of the Korean Institute of Navigation
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• v.18 no.4
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• pp.49-57
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• 1994

In marine transportation of bulk cargoes such as crude oil. ore, coal etc., a lot of full form ship which have poor manoeuvrability were presented in many countries. Since ship manoeuvrability depends upon many parameters namely hydrodynamic derivatives, interference factors etc., as external forces, it is of great importance that we investigate these values of parameters on analysis of manoeuvrability. In this paper, we investigated and analyzed interaction coefficients among hull-propeller-rudder for a full form ship by captive model test in circulating water channel, and then compared with experimental results by PMM test. A tanker model ship which has 0.83 as block coefficient and MMG mathematical models were used in this experiment. Almost same tendencies were found in qualitative analysis, even though more serial experiments were demanded in quantitative analysis.

• Journal of Ship and Ocean Technology
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• v.1 no.1
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• pp.15-25
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• 1997

A series of towing tank tests were carried out for 18 full ship models of high block coefficients. The resistance coefficients and wake distribution at the propeller plane were measured and carefully examined. Regression analysis was employed to find out the relationships with the hull form parameters. Equations for wave resistance coefficient, form factor, and nominal wake are given. A harmonic analysis of measured wake was performed to look into the influence of the local stern shape on the magnitude of fluctuating wake components at three different radii. The amplitude of wake harmonics was also expressed by regression quations. It was found that the regression formulas were very useful in estimating resistance and circumferential wake characteristics of full ship models. It was also considered that the formulas presented in this paper could be utilized in the hull form improvement in a preliminary design.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2021.11a
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• pp.203-203
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• 2021

• Bulletin of the Society of Naval Architects of Korea
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• v.25 no.4
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• pp.28-38
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• 1988

This paper describes the statistical analysis method of predicting the ship resistance. The equation for the wavemaking resistance coefficient is derived as the principal dimensions and sectional area coefficients by using the wavemaking resistance theory and its regression coefficients are determined from the regression analysis of the resistance test results. The equation for the form factor is derived by purely regression analysis of the principal dimensions, sectional area coefficients and resistance test results. Also, it is shown that the wavemaking resistance can be minimize by varying the sectional area curve without changing the principal dimensions of the ship. This methods were applied to the resistance prediction of a bulk carrier. And the, the modified hull form with minimum wavemaking resistance was obtained and the reduction of effective power was confirmed by the resistance test.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.3
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• pp.49-59
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• 2004

The paper describes the preliminary ship design method using deterministic approach and probabilistic approach. In deterministic approach, there are computational aspects to applying not only the integration concurrently of principal dimension decisions and hull form variations but also hydrostatic coefficients that applied to optimization iterative process. Therefore, this paper developed that actual design concept at the preliminary ship design more than sequential design which separated in principal dimension decisions and hull form variations. Furthermore, a probabilistic approach at the preliminary ship design is applied to efficiently solve design information uncertainty that compared to deterministic approach.

• Bulletin of the Society of Naval Architects of Korea
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• v.9 no.1
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• pp.1-6
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• 1972

To contribute towards more accurate estimation of the virtual coefficient for the vertical vibration of the chine-type ship, experimentally obtained three-dimensional correction factors, J, of added mass of prismatic beams having cross section shape of hypotrocoid characters, slightly concaved Lewis form and elliptic form are investigated in connection with the applicability of an approximate analytical calculation method compared to that proposed by T. Kumai[6] for the Lewis form cylinders, and synthetically in compared with the experimental works on various cross section shapes of the other type by L.C. Burril et al[8] and the analytical works on the ellipsoid of revolution by F.M. Lewis[1] and J.L. Taylor[2]. The experimental results show that the aforementioned analytical method gives, unlike that for the Lewis form cylinders, considerably larger J-values for the chine-type cylinders, and that the influence of the character of the cross section shape on J-values is not remarkable in practical sense. Finally, considering in synthesis the experimental results on prismatic beams, the Burril's works on palabolic plan form and elliptic plan form, and that the chine-type ship usually has a hull form of transom stern, it is fairly safe to say, at the present stage, that adoptation of the Taylor's J-values will not results in any large error in estimation of the virtual inertia coefficients of the chine-type ships.

• Journal of Navigation and Port Research
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• v.29 no.8 s.104
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• pp.667-671
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• 2005

This study was carried out to examine the prediction of ship's manoeuvrability in initial design stage. New parameter representing basic hull form and stem shape were proposed. Captive model test were carried out to investigate the correlation coefficient between hydrodynamic coefficient and hull parameter. The results showed which parameter are positive correlation with hydrodynamic coefficient. Moreover correlation was examined between stem hull shape and ship's manoeuvrability. New empirical formulas for hydrodynamic coefficients were proposed These results can be used to predict a ship's manoeuvrability in initial design stage.

• Bulletin of the Society of Naval Architects of Korea
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• v.26 no.4
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• pp.14-26
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• 1989

This paper describes the method of statistical analysis and its programs for predicting the ship's powering performance. The equation for the wavemaking resistance coefficient is derived as the sectional area coefficients by using the wavemaking resistance theory and its regression coefficients are determined from the regression analysis of the model test results. The equations for the form factor, wake franction and thrust deduction fraction are derived by purely regression analysis of the principal dimensions, sectional area coefficients and model test results. The statistical analyses are performed using the various descriptive statistic and stepwise regression analysis techniques. The powering performance prognosis program is developed to cover the prediction of resistance coefficients, propulsive coefficients, propeller open-water efficiency and various scale effect corrections.

• Bulletin of the Society of Naval Architects of Korea
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• v.24 no.1
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• pp.17-28
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• 1987

The materials to develop a computer-based method for the wave resistance of a ship within the frame of Guilloton's wedge concept are presented in this paper. A systematic reliable procedure to retrieve the linearized hull corresponding to a given real hull form(the so-called inverse transformation) has been devised. The algorithm based on the present materials produces evidently accurate values of the H-functions, and the wave profiles and the wave resistance coefficients in good agreement with the experimental measurements.

• Bulletin of the Society of Naval Architects of Korea
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• v.8 no.1
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• pp.29-40
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• 1971

In order to study the problem on form factor of hull form, towing test of a full ship model was carried out for different initial trims under both full and half load conditions. The results were fully discussed on the mutual relations among initial trim, mean sinkage and trim change in run, and form factor. There exists optimum initial trim in regard to form factor. Mean sinkage and trim change in run can be expressed in a uninominal approximation in the form of $k_i{\cdot}{F_n}^{2.2}$. The coefficients of this approxmation are related linearly with the initial trim. Form factor changes according to Froude number. It is considered that the trim change in run is a main reason of the fact.