Performance Assessments of Organic Rankine Cycle With Internal Heat Exchanger Based on Exergetic Approach

YAMANKARADENİZ N., Bademlioglu A. H., KAYNAKLI Ö.

JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME, vol.140, no.10, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 140 Issue: 10
  • Publication Date: 2018
  • Doi Number: 10.1115/1.4040108
  • Journal Name: JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: organic Rankine cycle, exergy analysis, heat exchanger, exergy destruction, pinch point temperature difference, OPTIMAL EVAPORATION TEMPERATURE, WORKING FLUIDS, POWER, OPTIMIZATION, ORC, SELECTION, MIXTURES
  • Bursa Uludag University Affiliated: Yes

Abstract

This study makes energy and exergy analysis of a sample organic Rankine cycle (ORC) with a heat exchanger which produces energy via a geothermal source with a temperature of 140 degrees C. R600a is preferred as refrigerant to be used in the cycle. The changes in exergy destructions (of irreversibility) and exergy efficiencies in each cycle element are calculated in the analyses made based on the effectiveness of heat exchanger used in cycle and evaporator temperature changing between 60 and 120 degrees C for fixed pinch point temperature differences in evaporator and condenser. Parameters showing system performance are assessed via second law approach. Effectiveness of heat exchanger and temperature of evaporator are taken into consideration within the scope of this study, and energy and exergy efficiencies of cycle are enhanced maximum 6.87% and 6.21% respectively. Similarly, exergy efficiencies of evaporator, heat exchanger, and condenser are increased 4%, 82%, and 1.57%, respectively, depending on the effectiveness of heat exchanger and temperature of evaporator.