PARAMETRIC OPTIMIZATION AND PERFORMANCE ANALYSIS OF ORGANIC RANKINE CYCLE (ORC) FOR ENGINE WASTE HEAT RECOVERY

asme-orc2015 Tracking Number 36

In China, internal combustion engines (ICEs) have consumed over 66 percent of total fuel consumption. Several methods have been adopted for the engine waste heat recovery, therein, the organic Rankine cycle (ORC) can be used to recover waste heat from an ICE with its flexibility, high efficiency and outstanding economical performance. This study examines the parametric optimization and performance analysis of ORC system using genetic algorithm (GA) for engine waste heat recovery. The effects of three key parameters, including evaporation pressure, superheat degree, and condensation temperature, on the net power output per unit heat transfer area and exergy destruction rate under engine various operating conditions are analyzed. Subsequently, the performances of a finned-tube evaporator used in this ORC system are evaluated. The results indicate that the optimal evaporation pressures are mainly influenced by the engine operating conditions. Moreover, superheat degree and condensation temperature presents slight variation over the whole operating range. The ORC system achieves maximum net power output per unit heat transfer area of 0.74kW/m2. Furthermore, the maximum effective heat transfer area of the evaporator is 69%, which has great influence on the performance of the ORC system.