• 한국신재생에너지학회:학술대회논문집
• /
• 2011.05a
• /
• pp.164.2-164.2
• /
• 2011

지구온난화에 따른 대체에너지 자원확보가 국가적으로 중요한 과제로 대두되고 있고 여러 대체에너지원 중 국내의 해양에너지는 잠재량이 매우 높다. 여러 해양에너지 중에서 빠른 흐름을 이용하는 조류발전은 서해안과 남해안에 적용하기에 적합하며 해양환경을 보존하면서 많은 에너지를 생산할 수 있는 장점이 있다. 조류발전에서 1차적으로 에너지를 변환시키는 로터는 주요한 장치중의 하나로 여러 변수에 의해 그 성능이 결정된다. 로터의 블레이드 수, 형상, 단면적, 허브, 직경 등 여러 요소를 고려하여 설계되어야 한다. 또한 조류발전을 적용하는 해양환경에서 최대 출력을 생산할 수 있는 로터가 적용될 수 있도록 블레이드의 후류 영향을 고려해야한다. 본 논문에서는 날개요소이론을 바탕으로 수평축 조류발전 터빈을 설계하여 실험 및 유동해석을 통해 성능을 평가하고, 후류에 미치는 영향을 분석하였다.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.44 no.1
• /
• pp.68-74
• /
• 2008

This study is concerned with the development of the basic planing hull form of small fishing boat in 25 knots high speed. A series of model test to determine the optimum performance hull form of actual fishing boat with 10 gross tonnage was carried out for 5 models made available planing hull form in the circulation water channel. Model test was performed with the resistance test to study the hydrodynamic characteristics of model ships and the sinkage and trim measurement to investigate the stability of model ships and also the wave pattern observation to analyze the effectiveness of model ships. As the result, the planing hull form of P-4 with deep V type bow can be derived as the best hull form with good performance especially in ship's resistance efficiency showing less residual resistance and sinkage and trim and the spray effect, etc..

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.11a
• /
• pp.590-593
• /
• 2009

Tidal current power system is one of ocean renewable energies that can minimize the environmental impact with many advantages compared to other energy sources. Not like others, the produced energy can be precisely predicted without weather conditions and also the operation rate is very high. To convert the current into power, the first device encountered to the incoming flow is the rotor that can transform into rotational energy. The performance of rotor can be determined by various design parameters including numbers of blade, sectional shape, diameter, and etc. The stream lines near the rotating rotor is very complex and the interference effects around the system is also difficult to predict. This paper introduces the experiment of rotor performance and also the effect of design parameter on the performance of HAT rotor by CFD.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.41 no.3
• /
• pp.222-226
• /
• 2005

A series of model tests carried out at the CWC of WJFEL for the purpose of prediction of resistance for the performance and improvement of resistance by attaching appendage for the ship of 50 knots class planing hull. The resistance performance evaluation has been carried out for the bare hull and for the appendage hull with two different depth of vertical type wedges. In the bare model test, trim and sinkage is calculated for the planing hull and the resistance is calculated. For minimizing the resistance, wedge appendage is attached and tested. Analysis and tests shows that for a 12.5mm wedge, resistance is minimum and overall power tallied to 5636ps.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2001.05a
• /
• pp.53-59
• /
• 2001

In this Paper, the resistance performances of twin hull forms, which are simplified as two-dimensional wedge shape, are experimentally investigated in low and middle speed ranges to find out the effect of distance between two hulls and fore-body shape for the future hull form development of catamaran type sweeping vessel. The model tests are performed for seven different cases for three models in the circulating water channel(CWC) of Inha Technical College. The free surface flows are observed together to investigate the relation between resistance performance and free surface characteristics. A conceptual design for the modification of bow hull form is presented and the efficiency is discussed.

• Journal of Ocean Engineering and Technology
• /
• v.18 no.1
• /
• pp.80-84
• /
• 2004

The initial hull form of a 3 G/T and 30 knots class coastal leisure boat is newly developed. The performances measured, resistance, trim and sinkage, are investigated in a high-speed, circulating water channel (CWC). The effect of a fin attached on the hull side is studied together. Wave patterns are observed to clarify the relationship between the resistance performance and the wave characteristics. It can be found that the fin plays a role of increasing the resistance performance above a certain velocity.

• Journal of Ocean Engineering and Technology
• /
• v.13 no.2 s.32
• /
• pp.168-175
• /
• 1999

In the present paper, a hull form for the turtle boat type incinerating vessel was developed based on the Finite source Distribution Method(FDM) and 1-$C_p$ method. In order to obtain proper hull form within the limited time and budget, a computer program OCL(Optimization of $C_p$ and LCB) was developed adn used. For the confirmation of the theoretical results by OCL, these theoretical results were compared with results of model test in the circulating water channel (CWC)in Chosun University.

• International Journal of Ocean System Engineering
• /
• v.1 no.3
• /
• pp.144-147
• /
• 2011

The rotor that initially converts the flow energy into rotational energy is a very important component that affects the efficiency of the entire tidal current power system. Rotor performance is determined by various design variables. Power generation is strongly dependent on the incoming flow velocity and the size of the rotor. To extract a large quantity of power, a tidal current farm is necessary with a multi-arrangement of devices in the ocean. However, the interactions between devices also contribute significantly to the total power capacity. Therefore, rotor performance, considering the interaction problems, needs to be investigated to maximize the power generation in a limited available area. The downstream rotor efficiency is affected by the wake produced from the upstream rotor. This paper introduces the performance of a downstream rotor affected by wakes from an upstream rotor, demonstrating the interference affecting various gabs between devices.

• Journal of Ocean Engineering and Technology
• /
• v.22 no.3
• /
• pp.58-63
• /
• 2008

A 32-ft class leisure boat was newly developed using statistical analysis of actual ships. Resistance performances were investigated by testing models in a high-speed circulating water channel, and with the CFD method. The effects of a trim tab and of a fin attached at the hull side were studied together. Wave patterns were observed to clarify the relationship between resistance performance and wave characteristics. It was found that a trim tab and a side fin play a role in increasing resistance performance within a certain velocity range.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2002.10a
• /
• pp.89-93
• /
• 2002

Resistance performance of 6.67 G/T class fishing vessel is experimentally investigated in low and middle speed ranges to find out the effect of a new chine. The tests are performed for four different cases in the circulating water channel(CWC). Wave patterns are observed together to make clear the relation between the resistance performance and the wave characteristics. The results show that the new chine can be one of the effective device to reduce the resistance.