Impact of superheat and reheat on the thermal efficiency of Regenerative Organic Rankine Cycle (R-ORC) with optimized operating conditions

Organic Rankine cycle is a mature technology for recovering energy form a waste heat source of medium temperature. Internal heat exchanger, superheat and reheat are three improvement-performance modifications of Rankine cycles. Organic Rankine cycles including these three modifications have been analyzed in this paper: Regenerative-ORC, Reheat-Regenerative-ORC, and with/without superheating. The performance of the four configurations has been compared, and the effects of superheat and reheat has been analyzed. Based on their thermodynamic, ambient, and safety properties, ten working fluids were selected. The main operation conditions are optimized for each cycle configuration and fluid to maximize the thermal efficiency using the Particle Swarm Optimization algorithm. Without superheating, the reheating stage improves the thermal efficiency of the regenerative cycle a 5.4%, whereas with superheating the increment is 1.8%. Integrating superheating with reheating improve the exergetic efficiency of the regenerative cycle.