ANALYSIS OF PURE FLUID AND ZEOTROPIC MIXTURES UESD IN LOW-TEMPERRATURE REHEATING ORGANIC RANKINE CYCLES FOR POWER GENERATION

asme-orc2015 Tracking Number 71

The shortage of fossil energy sources boosts the development and utilization of renewable energy. Among various novel techniques, recovering energy from low-grade heat sources including industrial waste heat, geothermal energy and solar energy through power generation via organic Rankine cycles has been one of the focuses. Compared with basic organic Rankine cycle, reheating organic Rankine cycle includes a high pressure expander and a low pressure expander instead of a single expander, thus the thermal energy can be utilized more sufficiently. Investigations indicated that reheating organic Rankine cycle can improve the thermal performance of the system. In this paper, the cycle performance was mainly measured by the system net output work which was calculated by programming through MATLAB and REFPROP. By taking pure fluid M1 (R245fa) and zeotropic mixtures M2 (R245fa/R152a) and M3 (R245fa/R21) as the cycle working fluid, the influences of working fluid, mixtures component and reheat pressure ratio on low-temperature reheating organic Rankine cycle system were investigated. The results showed that taking zeotropic mixtures as cycle working was superior in the improvement of overall system thermal performance. In addition, the optimal mixtures component and reheat pressure ratio of reheating organic Rankine cycle system were obtained.