Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Power Optimization of Organic Rankine-cycle System with Low-Temperature Heat Source Using HFC-134a

저온 열원 HFC-134a 유기랭킨사이클의 출력 극대화

  • Baik, Young-Jin (New and Renewable Energy Department, Korea Institute of Energy Research) ;
  • Kim, Min-Sung (New and Renewable Energy Department, Korea Institute of Energy Research) ;
  • Chang, Ki-Chang (New and Renewable Energy Department, Korea Institute of Energy Research) ;
  • Lee, Young-Soo (New and Renewable Energy Department, Korea Institute of Energy Research) ;
  • Ra, Ho-Sang (New and Renewable Energy Department, Korea Institute of Energy Research)
  • 백영진 (한국에너지기술연구원 신재생에너지연구본부) ;
  • 김민성 (한국에너지기술연구원 신재생에너지연구본부) ;
  • 장기창 (한국에너지기술연구원 신재생에너지연구본부) ;
  • 이영수 (한국에너지기술연구원 신재생에너지연구본부) ;
  • 나호상 (한국에너지기술연구원 신재생에너지연구본부)
  • Received : 2010.05.19
  • Accepted : 2010.10.10
  • Published : 2011.01.01
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, an organic Rankine-cycle system using HFC-134a, which is a power cycle corresponding to a low-temperature heat source, such as that for geothermal power generation, was investigated from the view point of power optimization. In contrast to conventional approaches, the heat transfer and pressure drop characteristics of the working fluid within the heat exchangers were taken into account by using a discretized heat exchanger model. The inlet flow rates and temperatures of both the heat source and the heat sink were fixed. The total heat transfer area was fixed, whereas the heat-exchanger areas of the evaporator and the condenser were allocated to maximize the power output. The power was optimized on the basis of three design parameters. The optimal combination of parameters that can maximize power output was determined on the basis of the results of the study. The results also indicate that the evaporation process has to be optimized to increase the power output.

본 연구에서는 지열발전 등과 같은 저온 열원을 에너지원으로 하는 발전에 응용될 수 있는 HFC-134a 유기랭킨사이클의 출력 극대화를 수행하였다. 기존의 연구와는 달리, 본 연구에서는 열교환기해석에 유한체적법을 적용함으로써 작동유체의 열전달 및 압력강하 특성을 고려하였다. 또한, 열원과 냉각수의 입구온도 및 유량, 그리고 사이클을 구성하는 열교환기들의 총 전열면적을 구속 조건으로 함으로써, 기존 연구들에 비해 보다 현실적인 결과를 얻을 수 있도록 하였다. 사이클의 출력은 3 개의 설계인자를 이용하여 최적화 하였다. 시뮬레이션 결과, 출력을 극대화 시킬 수 있는 설계인자들의 최적조합이 존재함을 보였다. 또한, 출력 향상을 위해서는 증발과정의 개선이 우선적으로 필요함을 보였다.

Keywords

References

  1. Holdmann G., 2007, “The Chena Hot Springs 400kW Geothermal Power Plant: Experience Gained During the First Year of Operation,” Proceedings of Geothermal Resources Council Annual Meeting.
  2. Chang, K. C., 2009, “A study on Feasibility of Technology Development for Domestic Geothermal Power Plant System,” Project No. 2008-N-GE04-P-02, Ministry of Knowledge Economy, Republic of Korea.
  3. Saleh, B., Koglbauer, G., Wendland, M. and Fischer, J., 2007, “Working Fluids for Low-Temperature Organic Rankine Cycles,” Energy, Vol. 32, pp. 1210-1221. https://doi.org/10.1016/j.energy.2006.07.001
  4. Tchanche, B. F., Papadakis, G., Lambrinos, G. and Frangoudakis, A., 2009, “Fluid Selection for a Low-Temperature Solar Organic Rankine Cycle,” Applied Thermal Engineering, Vol. 29, pp. 2468-2476. https://doi.org/10.1016/j.applthermaleng.2008.12.025
  5. Hung, T. C., Wang, S. K., Kuo, C. H., Pei, B. S. and Tsai, K. F., 2010, “A Study of Organic Working Fluids on System Efficiency of an ORC Using Low-Grade Energy Sources,” Energy, Vol. 35, pp. 1403-1411. https://doi.org/10.1016/j.energy.2009.11.025
  6. Papadopoulos, A. I., Stijepovic, M. and Linke, P., 2010, “On the Systematic Design and Selection of Optimal Working Fluids for Organic Rankine Cycles,” Applied Thermal Engineering, Vol. 30, pp. 760-769. https://doi.org/10.1016/j.applthermaleng.2009.12.006
  7. Madhawa Hettiarachchi, H. D., Golubovic, M., Worek, W. M. and Ikegami Y., 2007, “Optimum Design Criteria for an Organic Rankine Cycle Using Low-Temperature Geothermal Heat Sources,” Energy, Vol. 32, pp. 1698-1706. https://doi.org/10.1016/j.energy.2007.01.005
  8. Dai, Y., Wang, J. and Gao, L., 2009, “Parametric Optimization and Comparative Study of Organic Rankine Cycle (ORC) for Low Grade Waste Heat Recovery,” Energy Conversion and Management, Vol. 50, pp. 576-582. https://doi.org/10.1016/j.enconman.2008.10.018
  9. Lewis, R. M. and Torczon, V., 2002, “A Globally Convergent Augmented Lagrangian Pattern Search Algorithm for Optimization with General Constraints and Simple Bounds,” SIAM Journal on Optimization, Vol. 12, pp. 1075-1089. https://doi.org/10.1137/S1052623498339727
  10. Genetic Algorithm and Direct Search Toolbox 2 for MATLAB User’s Guide, 2007, The MathWorks Inc.
  11. Starling, K. E., Fish, L. W., Iqbal, K. G. and Yieh, D., 1975, “Resource Utilization Efficiency Improvement of Geothermal Binary Cycles-Phase I,” prepared for the Energy Research and Development Administration, Report ORO-4944-3.
  12. Gungor, K. E. and Winterton, R. H. S., 1987, “Simplified General Correlation for Saturated Flow Boiling and Comparisons of Correlations with Data,” Chem. Eng. Res. Des., Vol. 65, pp. 148-156.
  13. Gnielinski, V., 1976, “New Equations for Heat and Mass Transfer in Turbulent Pipe and Channel Flow,” Int. Chem. Eng., Vol. 16, pp. 359-368.
  14. Shah, M. M., 1979, “A General Correlation for Heat Transfer During Film Condensation Inside Pipe,” Int. J. of Heat Mass Transfer, Vol. 22, pp. 547-556. https://doi.org/10.1016/0017-9310(79)90058-9
  15. Muller-Steinhagen, H. and Heck, K., 1986, “A Simple Pressure Drop Correlation for Two-Phase Flow in Pipes,” Chem. Eng. Process, Vol. 20, 297-308. https://doi.org/10.1016/0255-2701(86)80008-3
  16. Collier, J. G. and Thome, J. R., 1994, “Convective Boiling and Condensation,” 3rd ed., Clarendon Press, Oxford.
  17. Lemmon, E. W., Huber, M. L. and McLinden, M. O., 2007, NIST Standard Reference Database 23: Reference Fluid Thermodynamic and Transport Properties-REFPROP, Version 8.0, National Institute of Standards and Technology, Standard Reference Data Program, Gaithersburg.
  18. Ibrahim, O. M. and Klein, S. A., 1996, “Absorption Power Cycle,” Energy, Vol. 21, pp. 21-27. https://doi.org/10.1016/0360-5442(95)00083-6
  19. MATLAB Version R2009a, 2009, The MathWorks Inc.