Improving the Engine Efficiency Using a New Combined Refrigeration Cycle for Low-Temperature Heat Source (Waste Heat Recovery)

Abstract

Passenger and commercial internal combustion engines have relatively large dissipated thermal energy sources that can be used for initiating thermodynamic refrigeration cycles at low temperatures while improving engine efficiency. Researchers have focused on combined power-refrigeration cycles in past studies. This paper presents the operation and performance of a new combined refrigeration system driven by waste heat recovery within the internal combustion engines. For this purpose, the effects of several parameters on the performance of the cycle are examined. Results show that an increase in the engine water temperature, exhaust gas temperature, part-load ratio (PLR), generator temperature, as well as adsorption evaporator temperature had a positive effect on the performance of the cycle. However, the rise in condenser temperature of the adsorption cooling system leads to bad performance. Also, the results indicate that the application of the adsorption refrigeration cycle in the combined cooling cycle, along with the increase in the refrigeration cycle performance by up to 65%, also improves the efficiency of the internal combustion engine.