• 한국항해항만학회지
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• 제33권7호
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• pp.501-504
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• 2009

There are many difficulties to supply constant power to marine facilities which operate in the sea. Especially, there is a limit to stand alone power supply systems due to the influence of weather conditions. That's why a hybrid power supply system is required to overcome these problems. This paper will describe an Electronic Anti-Fouling System (EAFS) to maximise the power efficiency for a solar - wave hybrid power generation system. A main factor reducing the efficiency of a Wave Energy Converter (WEC) is due to the attachment of aquatic life forms. Therefore the aim of this research is to develop a simulation programme to enable the design of more efficient EAFS for hybrid power generation systems and to provide valuable data for production of more efficient EAFS.

• Journal of Electrical Engineering and Technology
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• 제9권6호
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• pp.1921-1927
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• 2014

A new method for optimizing the magnetic field gradient in the exciting coil of electronic anti-fouling (EAF) system is presented based on changing exciting coil size. In the proposed method, two optimization expressions are deduced based on biot-savart law. The optimization expressions, which can describe the distribution of the magnetic field gradient in the coil, are the function of coil radius and coil length. These optimization expressions can be used to obtain an accurate coil size if the magnetic field gradient on a certain point on the coil's axis of symmetry is needed to be the maximum value. Comparing with the experimental results and the computation results using Finite Element Method simulation to the magnetic field gradient on the coil's axis of symmetry, the computation results obtained by the optimization expression in this article can fit the experimental results and the Finite Element Method results very well. This new method can optimize the EAF system's anti-fouling performance based on improving the magnetic field gradient distribution in the exciting coil.

• 대한기계학회논문집B
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• 제29권11호
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• pp.1229-1238
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• 2005

The objective of the present study was to investigate the efficacy of physical water treatment (PWT) technologies using different catalytic materials and an electronic anti-fouling device in the mitigation of mineral fouling in a once-through flow system with mini-channel heat exchanger. Effects of flow velocity and water hardness on the effectiveness of PWT technologies were experimentally studied. The artificial water hardness varied from 5.0 to 10 mo1/m$^{3}$ as CaCO$_{3}$. For 10 mo1/m$^{3}$ solution, fouling resistance reduced by 13-40$\%$ depending on flow velocity and types of PWT devices. On the other hand, fouling resistance reduced by 21-29$\%$ depending on the PWT devices for 5 mo11m3 solutions. The PWT device using alloy of Cu and Zn as catalyst (CM2) was slightly more effective than the others. SEM photographs of scale produced from the 10 mol/m$^{3}$ solution at 1.0 m/s indicated that calcium carbonate scales without PWT devices were needle-shaped aragonite, which is sticky, dense and difficult to remove. Scales with the PWT devices showed a cluster of spherical or elliptic shape crystals. Both the heat transfer test results and SEM photographs strongly support the efficacy of PWT technologies using catalytic materials and an electronic anti-fouling device in the mitigation of mineral fouling.

• Journal of Advanced Marine Engineering and Technology
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• 제39권9호
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• pp.981-986
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• 2015

지구온난화에 대한 심각성이 대두되면서 선박부문의 온실가스 배출에 관한 연구가 전 세계적으로 활발하게 진행되고 있다. 이에 반하여 국내 연구 수준은 기초에 그치고 있다. 본 논문에서는 선박으로부터 배출되는 이산화탄소의 여러가지 저감대책 중에서 운항손실과 투자비용을 최소화하면서 수행할 수 있는 방법으로 전자제어엔진 사용, 트림 최적화, 프로펠러 연마 및 친환경 방오도료의 사용을 선정하였다. 선정된 저감대책들을 운항실습선에 적용하여 시험 운항을 실시하였고 연료소비율에 미치는 영향을 분석하였다. 그 결과, 각 대책들은 약 1~5%의 연료소비율 저감 효과가 있었고 이를 에너지효율운항지수 산출에 적용하면 약 1~5%를 감소시키는 것을 알 수 있었다. 향후 국제적 환경규제를 제정할 때 우리나라에게 유리하도록 대응하기 위해서는 에너지효율운항지수에 대한 연구에도 지속적인 노력이 필요하다고 사료된다.