Thermodynamic and Optimal Analysis of Turbine-Bleeding Organic Rankine Cycle
Organic Rankine cycles (ORCs) with turbine bleeding which is coupled to a direct contact heat exchanger are typically designated as regenerative ORCs and these cycles closely resemble the ORC with regenerator. This paper presents a thermodynamic and optimal performance analysis of turbine-bleeding ORC with and without regeneration for the recovery of low-grade finite thermal energy. The effects of system parameters and working fluid on the system performance were theoretically investigated. Results showed that the performance of basic ORC can be improved by incorporating both turbine bleeding and regeneration and there exists an optimum turbine bleeding pressure for the maximum second-law efficiency. The system performance under the optimal condition is significantly influenced by the turbine inlet pressure, regeneration, and working fluid. Index Terms - Organic Rankine cycle (ORC), turbine bleeding, optimal condition, second-law efficiency, exergy.