200kW ORC 터빈 개발 및 구성

한상조(Sangjo Han),서종범(JongBeom Seo) 대한기계학회 2014 大韓機械學會論文集B Vol.38 No.12

최근 전세계적으로 재생에너지의 관심이 증가하고 있다. 그 중 많은 관심을 받고 있는 것이 상대적으로 낮은 온도의 폐열을 사용하는 유기랭킨사이클(ORC)이다. 유기랭킨사이클은 기존의 증기터빈사이클과 유사한 기술을 사용하지만 낮은 온도의 폐열을 사용하기 위해서 증기대신 냉매를 작동유체로 사용한다. 작동유체를 냉매로 사용함으로 인해 이상기체 가정을 사용할 수 없고, 이는 ORC 시스템에 이용되는 터빈의 설계를 좀 더 복잡하게 만든다. 또, 냉매의 큰 분자량과 복잡한 분자구조로 인하여 낮은 음속을 가지게 되고 이로 인해서 쉽게 초킹 조건에 접근하게 된다. 본 연구에서 R245fa 를 작동유체로 하여 입구온도 124℃에 팽창비 9 의 조건에서 터빈의 효율을 증가시키기 위해 다단으로 설계된 아음속 ORC 터빈을 설계하는 과정과 터빈의 성능에 대하여 설명하고자 한다. 설계된 터빈은 200kW 급의 ORC 발전 시스템에 사용될 예정이다. Recently, there has been a growing interest in sustainable energy. One method that has been used is an organic Rankine cycle using conventional turbine technology with a low-temperature waste heat source. A 200-kW organic Rankine cycle (ORC) system was designed for a waste heat recovery application using R245fa as the working fluid. A radial turbine running at 15,000 rpm was employed to generate more than 200 kW with an expansion ratio of nine. Because an ORC turbine uses a refrigerant as the working fluid, the ideal gas law was not employed to design the turbine. In addition, the complexity of the molecular structure of R245fa made it difficult to design the turbine. Because R245fa has an Ma value of one at a low velocity for the working fluid (about 1/3 of the speed of sound in air) at about 100°C, it easily reaches a supersonic flow condition with a small pressure expansion. To increase the efficiency of the turbine, a dual stage radial-type turbine with a subsonic speed was suggested. This paper will describe the design procedure and performance evaluation of the ORC turbine using R245fa.

내연기관에 적용하기 위한 10 kW급유기랭킨사이클의 구심 터빈에 관한 실험적 연구

신동길,김영민,류영현 한국마린엔지니어링학회 2018 한국마린엔지니어링학회지 Vol.42 No.4

Internal combustion engines are used as the main power source in various fields. They emit carbon dioxide during the combustion process. Among the various ways to reduce carbon dioxide, one would be to reduce fuel consumption. In this study, we compare and analyze the performance of the radial turbine applied to the expander of the 10 kW class ORC system. Waste heat of the engine is recovered to reduce the fuel consumption of the internal combustion engine. The ORC system was constructed using R134a as the working fluid, and the experiment was conducted. The expander is a permanent magnet synchronous type generator with two poles and an integral radial turbine. The maximum number of revolutions is 100,000 rpm. The expander is the most important core component to improve the efficiency of the ORC system. The heat source of the ORC system can be divided into exhaust heat and cooling water heat. The authors have constructed and tested a high temperature oil boiler to simulate the heat of the individual hot exhaust and a low temperature steam boiler, to simulate the engine coolant heat of the low temperature boiler. 내연기관은 다양한 분야에서 주 동력원으로 사용되고 있는데, 연소과정에서 이산화탄소를 배출한다. 이산화탄소를줄이기 위한 여러 가지 방법 중에서 연료소모량을 줄이는 방법이 있다. 본 연구에서는 내연기관의 연료 소모량을 줄이기 위해서 엔진 폐열 회수를 위한 10 kW급 ORC 시스템의 팽창기로 적용된 구심 터빈 성능을 비교, 분석하였다. R134a 를 작동유체로 사용하여 ORC시스템을 구성하여 실험을 수행하였다. 팽창기는 2극을 가진 영구자석동기 발전기와 일체형 구심 터빈으로서, 최대 회전수는 100,000 rpm 이다. 팽창기는 ORC 시스템의 효율향상을 위해서 가장 중요한 부품이라고 할 수 있다. ORC 시스템의 열원은 배기열과 냉각수열로 구분할 수 있다. 고온 열매체인 배기열을 모사할 수 있는고온 가스 보일러와 저온 열매체인 엔진 냉각수열을 모사할 수 있는 저온 스팀 보일러를 각각 구성하여 실험 하였다.

유기랭킨사이클 적용 스크롤 팽창기 성능 특성 연구

신동길(Dong Gil Shin),김영민(Young Min Kim),김창기(Chang Gi Kim) 대한설비공학회 2011 설비공학 논문집 Vol.23 No.12

The rapid increases in global energy demand and global warming need renewable energy sources such as solar thermal energy, biomass energy and waste heat. A ORC-based micro-CHP system(< 10 kWe) is one of the effective means to use renewable energy and solve energy problems because of its compactness, flexibilities and lower cost compared to other systems. The most important core components of the ORC is the expander which has a strong effect on the cycle efficiency. In the range of power output from 1 to 10 kW, the scroll expander is a good choice due to its performance and reliability. In this study, we have carried out an experimental study on an ORC equipped with oil-free scroll expander working with refrigerant R134a. We have measured power output and thermal efficiencies of the ORC and analyzed correlation between volumetric efficiencies of the expander and thermal efficiencies of the ORC.

선박폐열을 이용한 100 kW급 유기랭킨사이클의 성능특성

윤정인,손창효,설성훈,박상찬,임승택,이호생 한국동력기계공학회 2022 동력시스템공학회지 Vol.26 No.6

This study aims to investigate the performance characteristics of the 100 kW Organic Rankine Cycle (ORC) using ship waste heat. The heat source of ORC was steam generated by economizer, and the heat sink was seawater. Three cycles including the basic cycle, preheating cycle, and I.H.X (Internal heat exchanger) cycle were investigated. The results show that applying I.H.X can increase the efficiency of the cycle, and applying preheater can reduce the required mass flow rate of steam which is the heat source. Furthermore, it is recommended to lower the evaporation temperature and enhance the superheating degree to reduce the high expansion ratio, without system efficiencies decreased.

급액가열기, 재생기를 적용한 유기랭킨사이클(ORC)의 열역학적 효율에 관한 해석적 연구

박창용(Chang Yong Park),홍웅기(Woong-Ki Hong),김정민(Jung-Min Kim) 대한설비공학회 2011 설비공학 논문집 Vol.23 No.10

A numerical study was performed for thermodynamic efficiencies of a basic ORC (Organic Rankine Cycle), ORC with a FLH (Feed Liquid Heater), and ORC with a regenerator. The efficiencies of the basic ORC were higher in the order of R113, R123, R245ca, and R245fa for its working fluids. It was confirmed that an optimal FLH pressure existed to maximize efficiency of the ORC with a FLH. A correlation was developed to predict the optimal FLH pressure as a function of evaporation and condensation pressure and its average absolute deviation was 0.505%. The efficiency enhancement of the basic ORC with a FLH was higher than that with a regenerator. It was presented that the basic ORC efficiency could be improved more than 10% by a FLH with 30℃ condensation and over 110℃ evaporation temperatures.

저등급 열원의 변환을 위한 칼리나 사이클과 유기 랭킨 사이클의 엑서지 성능의 비교 해석

김경훈,정영관,고형종 한국수소및신에너지학회 2020 한국수소 및 신에너지학회논문집 Vol.31 No.1

The organic Rankine cycle (ORC) and the Kalina cycle system (KCS) are being considered as the most feasible and promising ways to recover the low-grade finite heat sources. This paper presents a comparative exergetical performance analysis for ORC and Kalina cycle using ammonia-water mixture as the working fluid for the recovery of low-grade heat. Effects of the system parameters such as working fluid selection, turbine inlet pressure, and mass fraction of ammonia on the exergetical performance are parametrically investigated. KCS gives lower lower exergy destruction ratio at evaporator and higher second-law efficiency than ORC. The maximum exergy efficiency of ORC is higher than KCS.

주택용 태양열 보일러를 적용한 유기랭킨사이클 열병합 (ORC) 발전시스템 최적화 설계 연구

김영민,신동길,김창기,이상태 한국에너지학회 2013 에너지공학 Vol.22 No.4

본 연구에서는 현재 난방용으로 활용되는 주택용 태양열 집열기에 유기랭킨사이클 발전시스템 (ORC) 을 적용하여 전력을 생산함과 동시에 응축열을 난방열로 활용하는 열병합 발전시스템 개발을 위한시스템 설계 해석이 수행되었다 최대 의 전력과 이상의 난방열을 공급할 수 있는 열병합 . 1kWe 10kWt 발전시스템을 목표로 하였으며 고온 및 고효율 집열을 위해 , CPC(Compound Parabolic Concentrator) 집열기를 적용하였다 집열기는 집열온도에 적합하며 이러한 열원의 온도범위에서 . CPC 100-200°C , 적합한 냉매로서 를 적용하였다 집열온도가 높아질수록 사이클 효율은 향상되지만 열손 ORC R245fa . 실에 의한 집열효율은 감소하므로 최대 발전출력을 위한 최적 집열온도가 존재하게 된다 응축온도는 . 감소할수록 발전출력은 증가하므로 난방열 공급을 충족하면서 최대한 응축온도를 낮게 할 필요성이있다 또한 팽창기의 탈설계 조건에서 효율 특성과 태양열 조건 변화에 따른 운전압력 범위를 고려 . 하여설계 팽창비를 목표 운전 압력비보다 낮도록 하여 저팽창 운전을 하도록 설계 하는 것이 유리함을제시하였다.

디젤발전기의 폐열회수를 위한 혼합냉매 기반 랭킨싸이클에 관한 연구

이태진(Tae Jin Lee),신경호(Kyeong Ho Shin),심다민(Da Min Shim),김주형(Joo Hyung Kim),정동수(Dong Soo Jung) 대한설비공학회 2018 설비공학 논문집 Vol.30 No.7

In this study, the Organic Rankine Cycle (ORC), based on mixed refrigerants, has been researched for recovering the waste heat of a diesel power plant. The simulation program has been developed to analyze the performance of ORC, which is operated by saturated jacket water of diesel engine and the ocean cooling water. The results show that the ORC efficiency and the power are 13.19% and 43.5 kW, respectively, when the cooling capacity of the evaporator side is 329.7 kW. The output power of ORC using R1233zd refrigerant, whose GWP is 4, is 2.7% higher than R245fa, which has been widely used in the ORC system and has a GWP of 1030. Considering the optimized UA, the multiplication of the overall heat transfer coefficient and the surface area, and the design of the evaporator and condenser can increase the efficiency of ORC from 13.19% to 14.82% and increase the power to 12.2%. Finally, the refrigerant mixed with R245fa, R1234yf and R1233zd can be properly selected for the design purpose, low GWP and performance, through results which are presented by the mixed ratio versus the system efficiency and GWP value.

Turbine Impeller 형상이 유동특성에 미치는 영향에 관한 연구

전언찬(Eon-chan Jeon),윤기호(Gi-Ho Youn),강창훈(Chang-Hun Kang) 한국기계가공학회 2014 한국기계가공학회지 Vol.13 No.4

Recently, research has been conducted to develop the ORC (organic Rankine cycle), to recover waste heat from facilities such as industrial plants ultimately to create mechanical or electrical energy. The ORC system consists of a heat exchange, a condenser, a pump and a boiler. In this paper, 84 flow analyses were conducted with 21 cases and three variables, i.e., a number of large wings, a number of small wings, and RPMs. R245fa was used as a refrigerant. The flow cavitation phenomenon was investigated through a flow analysis, and a flow stream analysis was conducted.

유기랭킨사이클(ORC)을 위한 주전열면 열교환기의 채널주름비에 따른 유동 및 열전달 특성

성민제(M.J. Sung),안준(J. Ahn) 한국전산유체공학회 2013 한국전산유체공학회 학술대회논문집 Vol.2013 No.10

A series of numerical simulation has been carried out to study thermo-hydraulic characteristics of a primary surface type heat exchanger, which is designed for the evaporator and condenser of a geothermal ORC. Working fluid is geothermal water at hot side and R-245fa, which is a refrigerant designed for ORC, at cold side. Amplitude ratio of the channel and Reynolds number are considered as design parameters. Nusselt number is presented for the Reynolds number ranging from 50 to 150 and compared to existing correlations. The result shows that higher amplitude ratio channel gives better heat transfer performance within the range of investigation.