• 대한조선학회논문집
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• 제50권2호
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• pp.95-103
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• 2013

Prediction of the running posture is important to evaluate the resistance by the numerical calculation for a high speed vessel. Especially for a planing craft having a large variation of running attitude it becomes more essential, but it can not be obtained easily because the running posture and the hydrodynamic forces including the resistance are interacted with each other. So iterative calculation to obtain the dynamic forces according to the changes in attitude is necessary, in this study, considering the calculated hydrodynamic force at the assumed draft as the additional buoyancy the corrected draft is calculated through satisfying the equilibrium between the buoyancy and the hull weight. To verify the derived method three kinds of hull forms were used with the results of model tests, R/V ATHENA and 150 tons class guide vessel for middle-speed semi-planing crafts, 28 feet fast boat for a high-speed planing boat. For all cases with several iterations the converged value of draft can be obtained, lastly the resistance and flow around hull were simulated by using VOF method.

• 대한조선학회논문집
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• 제56권3호
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• pp.200-210
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• 2019

High-speed planing craft is generally smaller than commercial vessels, for which not only the roll motion but also the pitch and heave motions are relatively large during operation However, if seakeeping performance of high-speed planing craft is evaluated by assessment methods of commercial vessels considering roll damping only, it would get unreasonable results due to excessive magnitudes of motion. This research aims at developing a procedure to evaluate seakeeping performance of high-speed planing craft reasonably well by considering responses of roll, heave and pitch motions. In addition, we tried to combine advantages of the potential flow method and CFD in this procedure, a so-called hybrid method, which uses the 3D panel method for the analysis of seakeeping performance, and tunes the damping coefficient using CFD analysis at a specific frequency. Finally, we evaluated seakeeping performance of coastal rescue boat in operation by applying the proposed procedure, and analyzed the results referring to the seakeeping criteria.

• 대한조선학회지
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• 제14권4호
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• pp.36-44
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• 1977

• 한국해안·해양공학회논문집
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• 제30권3호
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• pp.95-102
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• 2018

고속 주행시 마찰저항을 감소시키기 위해 선체의 선저부분의 모양을 변화시키는 등 최근 관련 분야의 개발이 이루어지고 있는 바, 본 개발에서는 기하학적으로 고속활주선의 스텝 단면을 유선형(streamlined type) 구조로 제작해 침수 표면적에 의한 마찰저항의 최소화를 목적으로 준비하였다, 본 개발의 목적은 어업의 각종 위급상황 및 안전성을 고려한 고속활주선의 구조설계를 기반으로 하여 어업의 특수성 및 작업특성(어군 추적 및 어획물 출하)을 고려한 최적선형으로서 유선형 마찰저감형 고속활주선을 제작하는데 그 목표가 있으며, 이 과정에서 제작된 성과물에 대한 성능평가를 수행하여 정량적 목표치를 확보하고자 함에 본 기술개발 논문의 소개 배경이 있다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권3호
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• pp.500-508
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• 2015

High-speed heavy loaded monohull ships can benefit from application of drag-reducing air cavities under stepped hull bottoms. The subject of this paper is the steady hydrodynamic modeling of semi-planing air-cavity hulls. The current method is based on a linearized potential-flow theory for surface flows. The mathematical model description and parametric calculation results for a selected configuration with pressurized and open air cavities are presented.

• 한국해양공학회지
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• 제11권3호
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• pp.89-94
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• 1997

In the design of high speed fishing vessel, its hull form has to be decided from a view point of resistance and propulsion performance without negelction of seakeeping characteristics. In spite of many efforts, the performance improvement by hull form itself has its limitations, specially for high speed craft. In this paper, the development of performance of resistance and seakeeping improving appendage for high speed planing hull on behalft of the hull form of fishing vessel has been introduced. The developed appendage verified its effectiveness in the full scale test.

• 한국산학기술학회논문지
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• 제19권10호
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• pp.418-423
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• 2018

최근 국내에서는 해양레저 산업의 활성화와 세계 해양레저 시장 진출을 위해 고부가가치 레저선박에 대한 연구개발이 활발히 진행되고 있다. 레저선박의 소재로는 물성이 우수하고 경량선체의 제작이 가능한 FRP(Fiber Reinforced Plastic) 복합재료가 널리 사용되고 있으며, FRP 복합재료로 제작되는 레저선박의 구조안전성 확보를 위한 설계기술 개발이 중요한 연구개발 목표중의 하나가 되고 있다. 본 연구에서는 RTM(Resin Transfer Molding) 공법으로 제작되는 FRP 복합재료 소재의 샌드위치 판넬을 주 구조부재로 하는 8m급 고속 활주선형 레저보트의 설계안에 대하여 구조강도를 평가하였다. 한국선급의 고속 경구조선 규칙 및 적용지침에 의거하여 선체 구조 안전성 검증을 위한 선저 슬래밍 충격하중 분포를 구하고, 샌드위치 구조의 복합재료 판을 등가의 굽힘 강성을 갖는 단일 재료의 등방성 판으로 치환하여 구조 해석을 수행하였다. 해석 결과를 실 제작 부재 시험편에 대한 강도 시험 결과와 비교한 결과 모든 내부 구조부재가 요구 강도를 충분히 만족함을 확인하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권2호
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• pp.323-332
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• 2014

High-speed marine vehicles can take advantage of aerodynamically supported platforms or air wings to increase maximum speed or transportation efficiency. However, this also results in increased complexity of boat dynamics, especially in the presence of waves and wind gusts. In this study, a mathematical model based on the fully unsteady aerodynamic extreme-ground-effect theory and the hydrodynamic added-mass strip theory is applied for simulating vertical-plane motions of a tunnel hull in a disturbed environment, as well as determining its steady states in calm conditions. Calculated responses of the boat to wind gusts and surface waves are demonstrated. The present model can be used as a supplementary method for preliminary estimations of performance of aerodynamically assisted marine craft.

• Journal of Advanced Marine Engineering and Technology
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• 제31권5호
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• pp.606-613
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• 2007

The 6m class high speed boat is developed with a durable hull and inflatable tube, which is called RIB(Rigid Inflatable Boat), for the purpose of marine leisure. In the stage of the conceptual design, its requirements to be optimized are determined based on the presented information of similar marine leisure RIBs. The 3-D graphical technique using Marine Rhino is utilized to optimize the compartment layout of RIB. The stability analysis is performed for the light and full load conditions with and without the inflatable tube. In addition, the sea keeping and hydrodynamic performance was tested using the proto-type ship in the sea condition. From the results of the computation and the sea trial test, it shows that the performance of the marine leisure RIB satisfies the speed, the convenience, and the stability requirements. This study provides the typical information of the design factors and the procedure to manufacture the marine leisure RIB.

• 한국해양공학회지
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• 제27권6호
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• pp.1-6
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• 2013

A 25ft class fishing leisure boat is developed, and the resistance performances are investigated by a model test in a high-speed circulating water channel. The design speed of the developed ship is 25 knots using a 150 ps outboard engine. A catamanan type hull form using a planing section is adopted considering the Froude number and large deck area. The effect of a center body attached on the bottom of the cross deck is studied under various conditions. Wave patterns are observed to make clear the relationship between the resistance performance and the wave characteristics. The results show that the shape of the center body and the position of the chine line can have a strong effect on the resistance performance in a certain velocity range.