Thermodynamic Analysis and Performance Evaluation of a Proposed Novel Combined Cooling and Power System

Abstract

Abstract — A novel combined cooling and power (CCP) system, wherein an organic Rankine cycle is coupled with a compressor-driven ejector refrigeration cycle, is proposed. The ejector primary flow of this refrigeration system comes from one of the streams that is pumped from the condenser, which is unconventional from the existing studies wherein the turbine exhaust is its primary flow source. Parametric analysis was conducted to study the effects of the heat source and evaporator temperature, and entrainment ratio on the coefficient of performance (COP) and exergy efficiency of the proposed system using three working fluids, namely R123, R141b, and R245fa. In the novel setup, the COP improvement can be theoretically associated to the produced turbine power that reduces the power input to the system. Among the parameters observed, the entrainment ratio and evaporator temperature had the greatest effect on the performance of the system. The system exergy efficiency varies inversely with entrainment ratio and evaporator temperature; on the other hand, the COP improves with the increase in the evaporator temperature and decrease in the entrainment ratio. The performance of three working fluids was also investigated. Among the three refrigerants, the system that used R141b had the highest COP and exergy efficiency at 3.26 and 46.92%, respectively.

Keywords — combined cooling and power system, ejector, exergy analysis