Buket Boz and Alvaro Diez
Comparative Study of SubCritical and Supercritical ORC Applications for Exhaust Waste Heat Recovery
119 - 127
2018
12
2
International Journal of Energy and Power Engineering
https://publications.waset.org/pdf/10008559
https://publications.waset.org/vol/134
World Academy of Science, Engineering and Technology
Waste heat recovery by means of Organic Rankine
Cycle is a promising technology for the recovery of engine
exhaust heat. However, it is complex to find out the optimum
cycle conditions with appropriate working fluids to match exhaust
gas waste heat due to its high temperature. Hence, this paper
focuses on comparing subcritical and supercritical ORC conditions
with eight working fluids on a combined diesel engineORC
system. The model employs two ORC designs, RegenerativeORC
and PreHeatingRegenerativeORC respectively. The thermodynamic
calculations rely on the first and second law of thermodynamics,
thermal efficiency and exergy destruction factors are the fundamental
parameters evaluated. Additionally, in this study, environmental
and safety, GWP (Global Warming Potential) and ODP (Ozone
Depletion Potential), characteristic of the refrigerants are taken
into consideration as evaluation criteria to define the optimal ORC
configuration and conditions. Consequently, the studys outcomes
reveal that supercritical ORCs with alkane and siloxane are more
suitable for high temperature exhaust waste heat recovery in contrast
to subcritical conditions.
Open Science Index 134, 2018