• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.3
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• pp.305-314
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• 2017

Asymmetric planing hulls are often used on high-speed catamarans. In this study, a linearized potential-flow method is applied for modeling steady hydrodynamics of single asymmetric hulls and their catamaran setups. Numerical results are validated with available experimental data and empirical correlations. Parametric calculation results are presented for the lift coefficient and the center of pressure for variable hull geometry, spacings, and speed regimes. The lift coefficient is found to increase at smaller hull spacings and decrease at higher Froude numbers and higher deadrise angles.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.9-9
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• 2017

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.232-233
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• 2017

In this research, tunnel stern was applied on the asymmetric high-speed catamaran to evaluate vessel's hydrodynamic performance by numerical method, and the tunnel stern types are distinguished by angle of inclination of tunnel exit region into 3cases ($0^{\circ}$, $3^{\circ}$ and $6^{\circ}$). Consequently, it is confirmed that the total resistances of tunnel stern which have $0^{\circ}$ of inclination are lower about 4.8-17.9% than the bare hull in the wide speed range, but those of $3^{\circ}$ and $6^{\circ}$ of inclination tunnel stern are higher than bare hull about 5-14% and 5-29%, respectively. On the other hand, trim angles of $0^{\circ}$ of inclination tunnel stern show similar trend with those of bare hull in whole ranges of FnV but those of $3^{\circ}$ and $6^{\circ}$ of inclination tunnel stern are stabilized and declined respectively after FnV=1.54. These phenomena indicated that increasing angle of inclination of tunnel exit region had negative influence on resistance performance, however, it could make vessel's operation performance better than bare hull.

• Journal of the Society of Naval Architects of Korea
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• v.34 no.4
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• pp.61-71
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• 1997

Numerical and experimental studies are carried out to analyse the resistance characteristics of a hydrofoil catamaran which is advancing on calm water with uniform speed. For the hydrofoil catamaran with modified Wigley hull which has asymmetric transverse section and transom stem, the studies are carried out for the range of Froude number 0.2 to 1.0 and the angle of attack of the hydrofoil $0.0^{\circ}$ to $3.0^{\circ}$. The model tests are carried out in the ship model basin of Inha University. Also the numerical computations using a finite difference method are performed for the simulations of fluid flow around the hull form and the results are compared with the results of the model tests. The present computation results show well quantitative agreement with the experimental results. The experimental results show that the shape and angle of attack of the foils exerts a considerable influence on the running posture and resistance performance of ship.