• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.867-875
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• 2014

Planing crafts were specifically designed to achieve relatively high speeds on the water. When a planing craft is running at high speed, dynamic pressure on the bottom makes the boat rise on the surface of the water. This reduces the area of the sinking surface of the boat to increase air resistance. Air resistance means the resistance that occurs when the hull and deck house over the surface of the water come in contact with the air current. In this paper, we carried out a CFD numerical analysis to find optimal deck houses that decreased air-resistance on the water when planing crafts are running at high speed. We finally developed the deck house shape of high-speed planing crafts that optimally decreased air resistance.

• 한국항해항만학회지
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• 제32권10호
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• pp.759-764
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• 2008

활주형선이 수면 위를 활주하여 고속이 가능하기 위해서는 특별하게 설계되어 진다. 대부분의 활주형선은 충격하중을 줄이고 황요, 종요 등의 운동성능을 개선시키기 위하여 스프레이 스트립을 설치하며, 고속에서는 파형개선과 양력발생으로 스프레이저항과 마찰저항이 감소되는 것으로 알려져 있다. 이에, 본 논문에서는 모형시험을 통하여 스프레이 스트립의 부착 유무에 따른 고속 활주형선의 저항특성을 비교, 분석하였으며, 시험결과, 스프레이 스트립 부착 고속 활주형선이 미 부착 선형에 비해서 $3.0{\sim}5.0%$의 저항감소 효과를 확인할 수 있었다.

• 대한조선학회논문집
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• 제44권5호
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• pp.534-541
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• 2007

This paper suggests the mathematical method for the estimation of the required engine output for WIG crafts. The engine size of a WIG craft Is a key parameter in the design stage, because WIGs should overcome the hump drag during the take-off. Therefore, it is very important for a WIG designer to estimate required power and state change during take-off. The mathematical method was developed based on the steady planing state model of a planing boat. Through numerical calculations on various take-off states, it was found that the suggested method could give reasonable estimation of required power and state change during take-off.

• 한국항해항만학회지
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• 제36권3호
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• pp.157-162
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• 2012

활주형선은 고속 운항시 선저에 동적압력을 발생시켜 선체를 부상시켜 침수표면적을 감소시킴으로서 저항이 감소하게 되어 고속의 항주가 가능하게 된다. 또한, 활주형선 선저부에 공기공급을 유도하면 고속 주행시 선저 공기공급에 따른 접수면 감소로 인하여 전체저항 감소에 따른 속도향상과 연비절감 효과가 있다. 이에, 본 논문에서는 고속 모형시험이 가능한 실 해역모형시험기법을 이용하여 고속 활주형선을 대상으로 선저부에 공기공급을 유도하여 침수표면적 감소에 따른 저항성능 개선을 위해 공기공급 유무에 따른 고속 활주형선의 저항특성을 비교, 분석하였다. 시험결과, 선저 공기공급 활주형선이 공기공급이 없는 선형에 비해 저항감소 효과가 현저하게 나타나는 것을 확인할 수 있었다.

• 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.

• Ocean Systems Engineering
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• 제4권4호
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• pp.293-308
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• 2014

Unlike the traditional displacement type vessels, the high speed planing crafts are supported by the lift forces which are highly non-linear. This non-linear phenomenon causes their motions in an irregular seaway to be non-Gaussian. In general, it may not be possible to express the probability distribution of such processes by an analytical formula. Also the process might not be stationary or ergodic in which case the statistical behavior of the motion to be constantly changing with time. Therefore the extreme values of such a process can no longer be calculated using the analytical formulae applicable to Gaussian processes. Since closed form analytical solutions do not exist, recourse is taken to fitting a distribution to the data and estimating the statistical properties of the process from this fitted probability distribution. The peaks over threshold analysis and fitting of the Generalized Pareto Distribution are explored in this paper as an alternative to Weibull, Generalized Gamma and Rayleigh distributions in predicting the short term extreme value of a random process.

• 한국항해항만학회지
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• 제32권8호
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• pp.583-588
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• 2008

활주형선은 고속 운항시 선저에 동적압력을 발생시켜 선체를 부상시킴으로서 저항이 감소하게 되어 고속의 항주가 가능하게 된다. 일반적으로 선저에 스텝을 적용한 선형은 일체형 활주형선에 비하여 고속 주행시 선저 공기공급에 따른 접수면 감소로 인하여 전체저항 감소에 따른 속도향상과 연비절감 효과가 있다. 본 논문에서는 고속 선형시험이 가능한 실 해역모형시험을 이용하여 선저 스텝개수에 따른 고속 Stepped Hull 선형의 저항성능을 비교, 분석하였다. 시험결과, 2개의 스텝을 가지는 선형이 최소저항 선형임을 확인할 수 있었다.