Investigation Study of Pressure Different Effect at Evaporator in Organic Rankine Cycle Simulator (ORCS) Using Low-grade Waste Heat

Abstract

Organic Rankine Cycle (ORC) was presented an efficient solution for low-grade waste heat exploitation, due to its uncomplicated mechanism, required less pressure, simple and compact components, and accessible maintenance. The evaporator has the characteristics of a pressure drop due to irreversibility which there was friction between working fluid and the heat exchanger channel walls. Working fluid are utilized for mixture-ratio between R123 and R245fa, and each individual refrigerant i.e. R123 and R245fa, all of them are changed in mass flow rate with verity of 0,1 kg/s and 0,2 kg/s. Difference of boiling point, freezing point, critical temperature and critical pressure could be identified by Ts diagram due to different molecular weight with the lowest of R245fa and the highest of R123. Pump performance produces volume rate and shows pressure different at evaporator with the highest ΔPevap of 0.95 bar, when utilized working fluid of R123. When an expansion process in the expander, molecule weight provides a more massive motion energy intake, therefore working fluid R123 has the highest expander power output and the greatest thermal efficiency