• 한국해양공학회지
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• 제24권6호
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• pp.103-108
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• 2010

WIG crafts are high speed vessels with the features of a dynamic supported craft. These crafts, which are predominantly lightweight and operate at substantially greater speeds than conventional craft, could not be accommodated under traditional maritime safety instruments. WIG crafts inherently possess more hazard factors than conventional ships because of their relatively high speed, lightweight, and navigational characteristics, and an accident is likely to cause damage to the ship and a high loss of life. Because WIG crafts are composed of many systems and subsystems, the safety assessment of a WIG must use a commercial software system in the design stage. This paper reviews a safety assessment process and methodology proposed by the IMO interim guideline, which were developed in view of the configuration of WIG crafts. This safety assessment system was developed to fit the WIG's safety assessment process using a reliability analysis system widely used in commercial systems. The FHA was performed on the functional hazards of systems in the conceptual design stage.

• 대한조선학회논문집
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• 제46권2호
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• pp.179-188
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• 2009

WIG crafts are a high speed vessel with features of dynamic supported craft. These crafts, which are predominantly of light weight and operate any substantially greater speeds than conventional craft such as bulk carrier, tanker, container ship, etc., could not be accommodated under traditional maritime safety instruments. It means that there is the need for risk and safety levels to be assessed on a holistic basis, recognizing that high levels of operator training, comprehensive and thoroughly implemented procedures, high levels of automation and sophisticated software can all make significant contributions to risk reduction. To response this requirement, the Interim Guideline for WIG craft(MSC/Circ.1054) were developed in the view of the configuration of WIG craft, which fall between the maritime and aviation regulatory regimes. This paper reviews a safety assessment process and methodology to be used in the design phase of a new ship. The process and methodology is based on the risk-based approach and is applied to safety assessment in concept development phase of small WIG craft in the 20-person class.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 추계학술발표회
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• pp.172-172
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• 2017

• 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.

• 대한조선학회논문집
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• 제48권5호
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• pp.381-389
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• 2011

In this study, we are focusing our attention on lift characteristics of the low aspect wings for Wing-In Ground effect crafts (WIG). Experimental measurements at an open-type wind tunnel are carried out and results are comparatively presented. In order to simulate the realistic ground condition in where the WIG craft is flying, moving ground is implemented by a conveyor belt rotating with the same velocity of the inflow. We consider two different wings (NACA0012 and DHMTU section) which have four different aspect ratios (0.5, 1.0, 1.5 and 2.0). Forces acting on the wings are measured and lift characteristics are elaborately investigated for various different conditions. In addition, end-plate effects are estimated. Results are validated by comparing with theoretic solutions of the symmetric airfoil. Present results show that ground effects are differently generated in moving or fixed ground conditions, and hence left characteristics are affected by the ground condition. Consequently, accurate aerodynamic forces acting on the WIG craft are guaranteed in a realistic moving ground condition.

• 해양환경안전학회지
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• 제19권5호
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• pp.491-496
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• 2013

수면비행선박의 지위가 국제해사기구(IMO)에서 선박으로 분류하는 것으로 결론지은 이후, 국내외적으로는 몇몇 규칙과 권고 사항들이 개정 및 승인되었다. 하지만 정작 수면비행선박의 종류 및 운항특성을 고려한 항법에 관해서는 규정이 미비하고, 수면비행선박간 항법에 관련해서는 규정이 되어 있지 않다. 이러한 상황에서, 현행 법령상에 다른 선박들과 수면비행선박간의 책임 관계를 명확히 하기 위하여 서로 시계에 항법상의 수면비행선박 관련 규정을 모든 시계로의 항법상으로 이동할 것과 수면비행선박간 안전통항을 확보하기 위하여 타입 'B'와 'C'의 수면비행선박이 타입 'A'의 수면비행선박을 피항해야 한다는 규정이 신설되어야 한다고 판단된다.

• Ocean Systems Engineering
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• 제6권3호
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• pp.245-264
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• 2016

The iterative boundary element method (IBEM) developed originally before for cavitating two-dimensional (2-D) and three-dimensional (3-D) hydrofoils moving under free surface is modified and applied to the case of 2-D (two-dimensional) airfoils and 3-D (three-dimensional) wings over water. The calculation of the steady-state flow characteristics of an inviscid, incompressible fluid past 2-D airfoils and 3-D wings above free water surface is of practical importance for air-assisted marine vehicles such as some racing boats including catamarans with hydrofoils and WIG (Wing-In-Ground) effect crafts. In the present paper, the effects of free surface both on 2-D airfoils and 3-D wings moving steadily over free water surface are investigated in detail. The iterative numerical method (IBEM) based on the Green's theorem allows separating the airfoil or wing problems and the free surface problem. Both the 2-D airfoil surface (or 3-D wing surface) and the free surface are modeled with constant strength dipole and constant strength source panels. While the kinematic boundary condition is applied on the airfoil surface or on the wing surface, the linearized kinematic-dynamic combined condition is applied on the free surface. The source strengths on the free surface are expressed in terms of perturbation potential by applying the linearized free surface conditions. No radiation condition is enforced for downstream boundary in 2-D airfoil and 3-D wing cases and transverse boundaries in only 3-D wing case. The method is first applied to 2-D NACA0004 airfoil with angle of attack of four degrees to validate the method. The effects of height of 2-D airfoil from free surface and Froude number on lift and drag coefficients are investigated. The method is also applied to NACA0015 airfoil for another validation with experiments in case of ground effect. The lift coefficient with different clearance values are compared with those of experiments. The numerical method is then applied to NACA0012 airfoil with the angle of attack of five degrees and the effects of Froude number and clearance on the lift and drag coefficients are discussed. The method is lastly applied to a rectangular 3-D wing and the effects of Froude number on wing performance have been investigated. The numerical results for wing moving under free surface have also been compared with those of the same wing moving above free surface. It has been found that the free surface can affect the wing performance significantly.