폐열회수 이용을 위한 초임계 이산화탄소발전시스템 탈설계 성능에 대한 연구

안윤한(Yoonhan Ahn),차재은(Jae Eun Cha),서한(Han Seo),이선일(Sunil Lee),정흥준(Heung June Chung) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.12

As the global climate change becomes substantial, desire to improve power system efficiency increases gradually. Power generation by utilizing the waste heat of gas turbine exhaust flow is another increasing market. Supercritical CO₂ cycle is gaining interests with several benefits: (1) high efficiency in the mild turbine inlet temperature range (450-650℃), (2) simple layout configuration and (3) small foot print coupled with compact heat exchangers and turbomachineries. On and off-design performance of supercritical CO₂ power system based on the component design variables is discussed in this paper. Preliminary design of supercritical CO₂ recuperated layout to make use of the waste heat from gas turbine (LM-2500) exhaust flow is designed and the corresponding turbomachineries and heat exchangers are designed. The compressor inlet condition is designed close to the critical point to improve system efficiency due to low compression work. Printed Circuit Heat Exchangers (PCHE) are designed for the S-CO₂ system because it can operate under high temperature and pressure condition. Radial turbomachineries design parameter and performance maps are generated from in-house code. Based on preliminary component design parameters, off-design performance is analyzed for the condition of cooling water temperature change. As cooling temperature increases, overall system mass flow rate and turbine power decreases, while the compression work increases.

마이크로 가스터빈 성능 예측 프로그램 개발

김정호(Jeong ho Kim),김민재(Min jae Kim),강도원(Do won Kang),김동섭(Tong seop Kim),박필제(Pil Je Park) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.12

In this study, an in-house program to predict steady state operation of micro gas turbines is constructed using Matlab Simulink. The program consists of two parts: design and off-design simulations. The program is fully modular in its structure. Performance of each component (compressor, combustor, turbine, recuperative heat exchanger and pipe elements) is calculated in a separate calculation module using mass and energy balances as well as models for off-design characteristics. The off-design modules of compressor and turbine use performance maps, which are program inputs. The off-design operation of a micro gas turbine which is being developed is predicted by the program. The prediction results are compared with those by commercial software, and the validity of the program is confirmed.

판형 열교환기의 탈설계 성능해석 및 실험

한동원,신지영,손영석,송치성 대한설비공학회 2004 설비공학 논문집 Vol.16 No.9

Design and off-design program is set up to analyze the performance of a plate heat exchanger. The program is verified by comparing the results with the experiment. The comparison shows that the predicted overall heat transfer coefficients are in good agreement with the measurements. Also the off-design performance according to the variations of inlet water temperature, flow rate, and the number of plates is analyzed to study the performance characteristic of a plate heat exchanger.

열회수증기발생기 해석방법을 개선한 가스터빈 복합발전 성능해석 프로그램 개발

박진희,이재홍,김동섭,정경우 한국유체기계학회 2022 한국유체기계학회 논문집 Vol.25 No.2

Accurate prediction of off-design performance is an important task in the design stage of gas turbine combined cycle (GTCC) power plants, and commercial software is generally used for that purpose. Most commercial software is easy to use in general but is hard to use effectively to guarantee a high accuracy because the mathematical models are very simple or not easy to be tuned to specific purposes. In the GTCC analysis, the analysis of the heat recovery steam generator (HRSG) is the major source of simulation uncertainty. To overcome the problem, a GTCC analysis program was developed, focusing on enhancing the convenience and versatility of the HRSG analysis. The program was coded with the Excel Visual Basic for applications (VBA). The p rogram was v alidated t hrough c omparison with r eference d ata. The maximum d eviation f rom the reference data was 0.27% in the design calculation and 3.26% in the off-design calculation, which are lower in comparison to commercial software.

유기랭킨사이클용 2단 구심터빈의 최적 탈설계점 작동에 관한 연구

조수용,최범석,임형수 한국동력기계공학회 2019 동력시스템공학회지 Vol.23 No.5

본 연구에서는 폐열, 태양열, 지열 등 열에너지원으로부터 전기에너지를 얻기 위한 ORC 시스템의 연구를 수행하였다. 팽창기는 2단 구심터빈으로 구성되어 있다. 열원의 열량이 변동하는 경우에 터빈이 탈설계점에서 작동하게 되므로, 탈설계 성능해석의 결과를 바탕으로 최대의 출력을 얻기 위한 연구를 수행하였다. ORC 시스템에서 증발기는 고정된 장치이므로 열원의 변동에 능동적인 대처가 안된다. 따라서 본 연구에서는 고정 전열면적을 기준으로 터빈에서의 성능을 얻었으며, 이를 기준으로 터빈에서의 운전조건을 설정하고, 터빈에서의 속도비의 변동을 고려하여 최대출력을 얻었다. 이러한 조정에 의하여 열원의 변동에도 불구하고 시스템의 효율은 설계점과 동일한 효율을 유지할 수 있었다.

급탕 히트펌프의 설계 및 탈설계점 운전 시뮬레이션

황인찬(Inchan Hwang),김민수(Min Soo Kim) 대한설비공학회 2022 대한설비공학회 학술발표대회논문집 Vol.2022 No.6

Water heating is the large energy user in the residential, commercial, industrial and power sectors. Using water supply heat pump(WSHP) system saves energy for generating hot water. This paper presents algorithm for testing the performance of WSHP under on-design and off-design conditions. We analyze the transient performance of the cycle of using and refilling half of the hot water in a flash tank. Compressor frequency is set as a variable for testing off-design condition. By comparing the tendency with the existing experimental data, the accuracy of the algorithm is determined.

PEMFC 의 열관리가 시스템의 성능에 미치는 영향

이정호(Jeong Ho Lee),명노성(No Sung Myung),김동섭(Tong Seop Kim) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11

An analysis program to simulate the operation of a PEMFC system was set up and system operation due to variations in working conditions of components, especially the heat management system, was simulated. The entire system includes a PEMFC stack and balance-of-plant component such as air supply unit, fuel supply unit and heat management unit, i.e. cooling system. Thermodynamic models of all components were made to evaluate the design performance of the entire system, and then off-design models were made to simulate operation of the entire system under arbitrary working condition. A parametric study was performed to examine the effect of varying operating conditions, especially the ambient condition and the operating condition of cooling system, on the operation and performance of the entire system

PEMFC의 열관리가 시스템의 성능에 미치는 영향

이정호(Jeong Ho Lee),명노성(No Sung Myung),김동섭(Tong Seop Kim) 대한기계학회 2011 大韓機械學會論文集B Vol.35 No.6

다양한 작동 조건에서 고분자 전해질형 연료전지의 성능 변화를 예측하기 위한 해석 프로그램을 구성하여 열관리가 시스템의 성능에 미치는 영향을 해석하였다. 전체 시스템은 연료전지 스택, 공기공급계, 연료공급계, 열 관리계로 구성 되었으며 각 구성부의 설계점을 고려하여 열역학적 모델링을 적용하였다. 외기온 변화와 냉각 시스템의 성능 변화에 따라 연료전지 스택의 온도 및 출력 변화가 예상되므로 탈설계 해석을 하여 전체 시스템의 성능 변화를 예측하였다. An analysis program to simulate the operation of a polymer electrolyte membrane fuel cell (PEMFC) system was set up, and system operation with variations in the working conditions of various components (especially the thermal management system) was simulated. The entire system included a PEMFC stack and balance-of-plant components such as an air-supply unit, a fuel-supply unit, and a heat-management unit (cooling system). Thermodynamic models of all components were made to evaluate the design performance of the entire system, and then off-design models were set up to simulate the operation of the entire system under arbitrary working conditions. A parametric study was carried out to examine the effects of varying the operating conditions (especially the ambient conditions and the operating conditions of the cooling system) on the operation and performance of the entire system.

유기랭킨사이클에서 열온 변동에 따른 재생기의 효과

조수용,조종현 한국동력기계공학회 2022 동력시스템공학회지 Vol.26 No.2

ORC 시스템은 재생에너지로부터 전기에너지를 얻기 위하여 사용되고 있다. 일반적으로 태양열, 지열, 풍력과 같은 재생에너지는 시간적, 환경적인 요소에 따라 일정한 에너지를 공급하지 못한다. 아울러 산업체의 폐열도 작업공정에 따라 일정한 폐열량이 공급되는 것이 아니다. 본 연구에서는 이러한 열원 변동이 발생되는 경우에 설계점을 기준으로 설계·제작된 장치를 기준으로 사이클 해석을 수행하였다. 아울러 시스템의 효율 향상을 위하여 적용되는 재생기의 효과를 분석하였다. 본 연구에 적용된 장치를 기준으로 최대 160도씨의 온도를 공급하는 열원으로부터 낮은 온도로 변동하는 경우에 대하여 적용된 100KW 급 ORC에서 시스템의 효율은 재생기의 사용에 의하여 약 0.5% 상승할 수 있으며, 이 때 시스템의 효율은 약 11% 정도였다.

가변 입구 안내익이 있는 축류압축기의 성능예측 방법에 관한 연구

김동현(Donghyun Kim),김상조(Sangjo Kim),김귀순(Kuisoon Kim),손창민(Changmin Son),김유일(You-il Kim),민성기(Seongki Min) 한국추진공학회 2012 한국추진공학회지 Vol.16 No.4

In this study, numerical method, stage stacking method based on the result of numerical method and scaled stage stacking method have been applied to predict the performance of a multi-stage axial compressor with inlet guide vane. The results obtained through three different methods for off-design conditions were compared with performance test data. And the effect the angle of variable inlet guide vane was also investigated. The three-dimensional numerical simulation has been performed by using flow analysis program, FLUENT™ 6.3 and the performance prediction based on the stage stacking method has been performed with compressor analysis code from NASA.