• Journal of Navigation and Port Research
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• v.33 no.5
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• pp.309-314
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• 2009

The influence of different appendage shape on the characteristics of hydrodynamic forces on Manta-type Unmanned Undersea Test Vehicle(MUUTV) was discussed experimentally. Fuselage only MUUTV model and two types of MUUTV model with different appendage geometries were considered as the subject of discussion Oblique tow experiment was carried out in circulating water channel with three MUUTV models. A point of difference in hydrodynamic force characteristics among three models was indicated. Furthermore, the linear hydrodynamic derivatives obtained from model experiment were compared with theoretical calculation results from slender body theory, added mass theory and etc. Based on the hydrodynamic force characteristics, motion stability of two types of MUUTV model with different appendage geometries was compared each other. Through the above analysis, the more suitable shape of appendage geometry was made clear.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.5-6
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• 2009

The influence of different appendage shape on the characteristics of hydrodynamic forces on Manta-Type Unmanned Undersea Test Vehicle(MUUTV) was discussed experimentally. Fuselage only MUUTV model and two types of MUUTV model with different appendage geometries were considered as subject of discussion Oblique tow experiment was carried out in circulating water channel with three MUUTV models. A point of difference in hydrodynamic force characteristics among three models was compared and discussed. Furthermore, the linear hydrodynamic derivatives obtained from model experiment were compared with theoretical calculation results from slender body theory, added mass theory and ete. Based on the hydrodynamic force characteristics, motion stability of two types of MUUTV model with different appendage geometries was discussed and compared each other. Through the above analysis, the more suitable shape of appendage geometry was made clear.

• Journal of the Society of Naval Architects of Korea
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• v.35 no.3
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• pp.38-45
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• 1998

In this parer, the effects of a skeg, rudder and stern hull form on the manoeuvrability of a container carrier with small length to draft ratio have been investigated through a series of model test. Rudder open water tests and PMM tests were carried out with varying rudder area, afterbody appendages and stern hull form to investigate their effects on the manoeuvrability. The MMG model developed in Japan was used for the manoeuvring simulation with experimentally obtained hydrodynamic coefficients. The result showed that the effects by the variation of stern profile and the skeg below stern bulb are much larger than those by any other types of appendages in improving directional stability of the vessel.

• Journal of Navigation and Port Research
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• v.30 no.5 s.111
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• pp.375-379
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• 2006

The keel attached on bottom of hull part prevents yacht from flowing sideway by sailing posture. The keel remove a heel moment and make the force of stability. The selection of suitable keel is important bemuse it has an influence on the safety. Also the appendage attached on bottom of keel part lower ballast weight center and have influence on hull stability. The optimum shape about the keel is very important. So this study has compared with characteristics of resistance depending on the shape of the lower part of fin keel in the same surface of water submersion, we have attached three different types of models of lower part of fin keels to the model ships using circulating water channel and analyzed resistance characteristics per shape to arrive at the optimum shape of reduction of resistance.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.06b
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• pp.235-239
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• 2006

The keel attached on bottom of hull part prevents yacht from flowing sideway by sailing posture. So this study has compared with characteristics of resistance depending on the shape af the lower part of fin keel in the same surface af water submersion, we have attached three different types of models of lower part of fin keels to the model ships using circulating water channel and analyzed resistance characteristics per shape to arrive at the optimum shape of reduction of resistance.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.238-240
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• 2017

파랑 중 선수파의 영향을 줄이기 위해 도입된 Axe Bow선형은 파랑 중 항해 시 선수부에 과도한 Spray현상이 발생한다. 이를 억제하고자 선수 부가물이 도입되었으나, 수치해석적 연구가 필요할 것으로 판단하였다. 선수 부가물은 Spray rail에서 착안하였으며, 구현이 쉽고 설계 파라미터를 제시 할 수 있는 Barge형상으로 적용하였다. 본 연구에서는 선수 부가물의 길이 변화에 따른 Axe Bow 선형의 Spray 억제를 수치해석적으로 고찰하였다.

• Journal of the Society of Naval Architects of Korea
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• v.34 no.2
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• pp.39-47
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• 1997

In the present paper, viscous flow fields around a wigley hull with appendages are analysed to study interactions between the hull and appendages. Navier-Stokes and continuity equations are solved by a finite volume method in a body-fitted coordinate system which conforms three dimensional ship geometries with appendages. A Sub-Grid Scale(SGS) turbulent model is used for a calculation of high Reynolds number flow. Numerical computations has been done for a Wigley hull form at $Rn=1.0{\times}10^6$. The results show that the present approach can predict, at least in qualitative sense, the influence of the appendages upon the flow field around a ship.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.5
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• pp.601-608
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• 2019

In this study, the effect of hull appendages on the high-speed catamarans with reverse bow shapes is compared and analyzed by numerical analysis and circulating water tank model test. The reverse bow shape showed an improved wave shape by shifting the generation position of forward divergent wave to the stern direction and was effective in resistance and stable running posture (Kim et al., 2019). In the model test results of the running performance as the wave patterns and the change of the running posture due to the fin fitted with the inner side of the inverted bow and the interceptor, 1) Trim characteristics of the inverted bow 2) Improvement of superposition of inner wave by Fin 3) The trim control by the fin and the interceptor is considered to be effective in reducing the impact of the two hull connection decks (wetdeck).

• Bulletin of the Society of Naval Architects of Korea
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• v.32 no.1
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• pp.21-27
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• 1995

초고속선에 관련된 점성유동은 저한성능 향상과 운항자세 제어를 위해 사용되는 다양한 선체부 가물의 저항 예측과 초고속선에 많이 사용되는 물분사 추진장치 입구 형상의 설계 그리고 임펠 러에 이르는 덕트 유동의 예측을 중심으로 관심을 받아왔다. 본 소고에서는 통상적인 선박의 경우와는 구별되는 초고속선 고유의 점성유동 특성에 관하여 간략히 논의하기로 하고 내용을 크게 선체-부가물 점성유동과 물분사 추진장치에 관련되어 있는 덕트유동으로 나누어 기술하 였다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.6
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• pp.359-366
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• 2014

This paper considered optimization method of appending a shape on a disc in an attempt to improve core functions, which are inherent in flow characteristics. The paper also verifies the optimization method of appendage shape with a Class 150 200A Butterfly valve. Then the design of experiment (DOE) with an orthogonal array is performed to analyze the effect of form parameters by grey relational analysis and analysis of mean (ANOM). And this study sets flow coefficient as an object functions for optimization, and the conventional disc model and the optimal appendage shape on disc model are compared by computational fluid analysis. The paper concludes that an optimal appendage shape on disc model achieves wider usability by a wider operating range.