Thermodynamic Analysis of an Organic Rankine Cycle System Integrated with a Condensation Chamber Working Under Vacuum Conditions

Konur O., Taşçıoğlu E. A., Yeleğen E., Aksu O. R., Çetin E., Çelik U.

Global Maritime Congress GMC'24, İstanbul, Turkey, 20 - 21 May 2024, pp.1-8

  • Publication Type: Conference Paper / Full Text
  • City: İstanbul
  • Country: Turkey
  • Page Numbers: pp.1-8
  • Dokuz Eylül University Affiliated: Yes

Abstract

The aim of this study is to thermodynamically analyze the integration of a condensation chamber that was placed

after the expander and operated under vacuum conditions in an organic Rankine cycle system of a marine

vessel. The proposed system was designed to substantially reduce the evaporation pressure; therefore, the

system can be established with cheaper components. The waste heat sources of jacket cooling water and

exhaust gas from the main engine were utilized. The condenser was cooled by seawater. The organic fluids were

selected as acetone, isobutane, isopentane, and benzene. Most of the working fluids utilized in conventional

waste heat recovery systems were not included in the analyses due to their improper thermodynamic properties

for the condensation state. A parametric study was carried out for main engine MCR loads of 51% and 100%

under conditions where high-pressure pump mass flow rate was theoretically varied between 4 kg/s and 7 kg/s,

and condensation tank pressure was reduced to 45 kPa. The results showed that the highest energy efficiencies

for all organic fluids were achieved with a 51% MCR engine load and a 7 kg/s high-pressure pump mass flow

rate. The best performance was yielded with isobutane with 21% thermal efficiency at 800 kPa evaporation

pressure.