Omer Kaynakli, Ali Husnu Bademlioglu, Nurettin Yamankaradeniz, Recep Yamankaradeniz

THERMODYNAMIC ANALYSIS OF THE ORGANIC RANKINE CYCLE AND THE EFFECT OF REFRIGERANT SELECTION ON CYCLE PERFORMANCE

The Organic Rankine cycle is a power-generation system for lower temperature ranges in which organic fluids with hydrocarbon components are used instead of water. Organic Rankine Cycles, which are suitable for heat recovery applications at low temperatures, can be used for generating electric energy from various waste heat sources. In this study, a thermodynamic analysis is conducted on an example Organic Rankine Cycle that is used to generate electric energy from a geothermal source. The working fluid to be used in the cycle was selected as R134a, R236fa, R245fa and R600a, which are commonly used. For these selected organic fluids, the required cycle performance to generate 1 MW of energy from the turbine was analyzed according to the geothermal source temperature (90-140°C), and the thermal efficiency of the cycle was calculated. The obtained results are presented comparatively with the help of the graphs. R245fa was defined to be more appropriate for the cycle as a refrigerant at constant work conditions.

Keywords:

Organic Rankine Cycle refrigerant, thermodynamic analysis, cycle performance, thermal efficiency,

PDF

___

Tchanche, B., Lambrinos, G., Frangoudakis, A., Papadakis, G., 2011, “Low-grade heat conversion into power using organic Rankine cycles-A review of various applications”, Renewable and Sustainable Energy Reviews, 15, 3963-3979.
Gang, P., Jing, L., Jie, J., 2010, “Analysis of low temperature solar thermal electric generation using regenerative Organic Rankine Cycle”, Applied Thermal Engineering, 30, 998-1004.
Roy, J.P., Mishra, M.K., Mishra, A., 2010, “Parametric optimization and performance analysis of a waste heat recovery system using Organic Rankine Cycle”, Energy, 35, 5049-5062.
Gozdur, A.B., Nowak, W., 2007, “Maximizing the working fluid flow as a way of increasing power output of geothermal power plant”, Applied Thermal Engineering, 27, 2074-2078.
Bertrand, F.T., George, P., Gregory, L., Antonios, F., 2009, “Fluid selection for a low-temperature solar Rankine cycle”, Applied Thermal Engineering, 29, 2468-2476.
Drescher, U., Bruggemann, D., 2007, “Fluid selection for the Organic Rankine Cycle (ORC) in biomass power and heat plants”, Applied Thermal Engineering, 27, 223-228.
Rayegan, R., Tao, X., 2011, “A procedure to select working fluids for solar Rankine cycle (ORCs)”, Renewable Energy, 36, 659-670.
He, C., Liu, C., Gao, H., Xie, H., Li, Y., Wu, S., Xu, J., 2012, “The optimal evaporation temperature and working fluids for subcritical organic Rankine cycle”, Energy, 38, 136-143.
Hung, T.C., 2001, “Waste heat recovery of organic Rankine cycle using dry fluids”, Energy Conversion and Management, 42, 539-553.
Yamamoto, T., Furuhata, T., Arai, N., Mori, K., 2001, “Design and testing of the Organic Rankine Cycle”, Energy, 26, 239-251.
Lui, B., Chien, K., Wang, C., 2004, “Effect of working fluids on organic Rankine cycle for waste heat recovery”, Energy, 29, 1207-1217.
Teng, H., Regner, G., Cowland, C., 2007, Waste heat recovery of heavy-duty diesel engines by organic Rankine cycle part II, working fluids for WHR-ORC”, SAE Technical Paper, 2007.01.0543.
Wang, X.D., Zhao, L., Wang, J.L., Zhang, W.Z., Zhao, X.Z., Wu, W., 2010, “Performance evaluation of a low-temperature solar Rankine cycle system utilizing R245fa”, Solar Energy, 84, 353-364.
Wang, X.D., Zhao, L., Wang, J.L., 2011, “Experimental investigation on the low temperature solar Rankine cycle system using R245fa”, Energy Conversion and Management, 52, 946-952.
Cihan, E., 2014, “Cooling performance investigation of a system with an organic Rankine cycle using waste heat sources”, Journal of Thermal Science and Technology, 34, 101-109.
Pulyaev, S., Akgoz, O., Cetin, B., 2013, “Recovery of waste heat in power plants using organic Rankine cycle”, 19th National Thermal Science and Technology Conference, 09-12 September, 978-982, Samsun, Turkey.
Ozden, H., Paul, D., 2011, “Power generation with organic Rankine cycle technology from low temperature heat sources. Case study: Saraykoy Geothermal Power Plant”, 10th National HVAC Engineering Congress, 13-16 April, 101-108, İzmir, Turkey.
Cengel, Y.A., Boles, M.A., 2011, “Thermodynamics: An Engineering Approach”, Seventh edition, McGraw-Hill Inc, USA.
Yamankaradeniz, R., 2004, “Fundamentals of Engineering Thermodynamics”, Nobel Publications, Turkey.
Yamankaradeniz, R.., Horuz, I., Kaynakli, O., Coskun, S., Yamankaradeniz, N., 2009, “Refrigeration Technology and Heat Pump Applications”, Dora Publishing, Turkey.