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

Öz

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. 

Anahtar Kelimeler

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

Kaynakça

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