Energy and exergy investigation of a hybrid refrigeration system activated by mid/low-temperature heat source

This study proposes a hybrid refrigeration system activated by mid/low-temperature sensible heat source with ammonia water (NH3-H2O) binary mixture as working fluid. The heat source is utilized in cascade in the hybrid system. This heat source is used to generate a superheated NH3-H2O mixture vapor, which is used successively in the power generation and compression subsystem and in the absorption and rectification subsystem to produce refrigerant vapor. Energy and exergy analysis results show that the Coefficient Of Performance, System Coefficient Of Performance, and exergy efficiency of the proposed system in the base case are 0.722, 0.485, and 23.1%, respectively. Effects of turbine inlet pressure, turbine outlet pressure, and solution concentration in the power generation subsystem on system performance are examined. This study provides a new refrigeration method to effectively utilize mid/low-temperature sensible heat. (C) 2015 Elsevier Ltd. All rights reserved.