• The KSFM Journal of Fluid Machinery
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• v.14 no.3
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• pp.18-22
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• 2011

This paper presents the transient performance analysis of a micro-hydro Pelton turbine for the osmotic power generation using the commercially available computational fluid dynamics (CFD) code, ANSYS CFX. The detailed flow field in the micro Pelton turbine with a single-jet is investigated by the CFD code adopted in the present study. Predicted characteristic curves agree fairly well with measured data for a prototype Pelton turbine over the normal operating conditions. The computational analysis method presented herein can be effectively applied to the hydraulic design optimization process of general purpose Pelton turbine runners.

• Journal of the Korea Convergence Society
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• v.6 no.1
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• pp.29-34
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• 2015

As smart grid techniques developed, public attention is concentrating on energy efficiency. So it is necessary to study on new renewable energy in order to manage the energy within micro grid consisting smart grid. Among them, small hydro energy has the advantage of being installable anywhere depending the amount of water used by the users within micro grid. This study examines if the measured value is appropriate for small hydro power generation by measuring generation quantity and operation rate of generator based on the sewage flow used by apartments and multi-unit dwellings where those users live. Some appropriate apartments and multi-unit dwellings generate electricity with small hydro generator using sewage as potential energy. This study intends to suggest more effective management by introducing energy management system and electricity storage device of micro grid.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.9
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• pp.958-963
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• 2012

Characteristics of off-grid hybrid renewable energy sources for high mountain villages are discussed. Considering reliability of electric power generation, Photovoltaic (PV)-wind hybrid and PV-hydro hybrid system are suggested. Connecting two or more villages with these hybrid systems, an extended hybrid off-grid can be formed. Sustainability of entire system is important in design of off-grid system, and income generation of the village people using the electricity should be considered.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.9
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• pp.67-72
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• 2014

Inflow or outflow from the water treatment plant and the sewage water has potential energy. If this potential energy can be converted into electrical energy by water turbine generator, it can help to save energy because of the high capacity utilization. So recently, micro hydro power plant is reviewed in the water treatment facility. If generation capacity is low, induction generator is primarily used. If output capacity is low, generated power is supplied to the inside load. Induction generator can cause voltage drop by the inrush current at a start-up and requires reactive power for magnetization. In this study, we analyzed the flow of power and voltage variation against inrush current that occurs when the induction generator starts under the terms that loads of linear and non-linear of the water purification plant are used. Analysis results are that the voltage drop is within an allowable range and the power factor is slightly reduced by the need of reactive power.

• The KSFM Journal of Fluid Machinery
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• v.18 no.6
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• pp.45-56
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• 2015

This paper aims to develop a submerged propeller turbine for micro hydropower plant which allows to sustain high values of efficiency in a broad range of hydrological conditions (H=2~6 m, $Q=0.15{\sim}0.39m^3/s$). The two aspects to be considered in this development are mechanical simplicity and high-efficiency operation. Unlike conventional turbines that have spiral casing and gear box, this is directing driving and no spiral casing. A 10 kW class turbine which has the most high potential of the power generation has been developed. The most important element in the design of turbine is the runner blade. The initial blade is designed using inverse design method and then the runner geometry is modified by classical hydraulic method. The design process is carried out in two steps. First, the blade shape is fix and then other components of submerged propeller turbine are designed. Computational fluid dynamics analyses based on the Navier-Stokes equations have been used to obtain overall performance data for the blade and the full turbine, respectively. The results generated by performance parameters(head, guide vane opening angle and rotational speed) variations are theoretically analysed. The evaluation criteria for the blade and the turbine performances are the pressure distribution and flow's behavior on the runner blades and turbine. The results of simulation reveals an efficiency of 91.5% and power generation of 10.5kW at the best efficiency point at the head of 4m and a discharge of $0.3m^3/s$.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.432-432
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• 2021

우리나라는 대부분의 에너지 공급을 해외에 의존하고 있는 실정이다. 산업통상자원부와 에너지경제연구원에서 발간하는 2018년 에너지통계연보(에너지경제연구원과 산업통상자원부, 2018)에 실린 2010년부터 2017년까지의 에너지수급 균형을 보면 원유, 천연가스, 석탄, 우라늄 등 평균 95.4%의 에너지를 수입하고 있는 실정이다. 수력 및 신재생에너지의 경우 기후변화에 대응하는 수단 그리고 정부의 저탄소에너지 전환 정책으로 인정받아 상대적으로 낮은 에너지 경제성에도 불구하고 꾸준히 보급되고 있다. 우리나라뿐만 아니라 독일, 프랑스, 영국, 중국 그리고 인도와 같은 세계 주요 국가들이 친환경 에너지 정책을 주도함에 따라 향후 신재생에너지의 공급 규모는 크게 확대될 것으로 전망된다. 중력 물 보텍스 마이크로 수력 발전 시스템은 시스템의 상하류부의 수두(hydraulic head) 차에 의해 저류조(basin)에서 발생되는 물의 보텍스 즉 소용돌이(whirlpool)를 이용하여 임펠러(impeller)를 회전시켜 전기에너지를 생산하는 친환경적 재생에너지의 일종이다. 또한, 시스템으로 유입되는 물은 전기에너지 생산을 위한 임펠러를 통과한 후 다시 하천으로 방류되므로 하천 수의 손실 그리고 하천의 물길도 거의 교란 시키지 않는다. 4가구 정도의 연간 가정용 전기 요구량인 12와 15kW 사이의 전기에너지를 생산하기 위해서는 발전시스템의 상류와 하류의 수두차가 단지 1.5에서 1.7m 이하이면 충분한 것으로 알려져 있다. 본 연구에서는 중력 물 보텍스 친환경 마이크로 발전 시스템을 구성하는 저류조(basin)에 대해 최대 발전효율을 발생시키기에 최적인 기하학적 형태를 도출하는 것이며, 이를 위해 저류조의 cone angle에 따른 다양한 저류조 직경 및 물 보텍스 생성을 위한 저류조 형태의 변화, 유입수로와 저류조와의 각도인 notch angle의 변화, 유입부 폭과 유출부 직경, 유입수로의 길이 그리고 유입수로에서의 초기수심과 같은 기하학적 매개변수를 변화시켜 모의를 수행하였다.