ENERGY AND EXERGY ANALYSIS OF A VAPOR ABSORPTION REFRIGERATION SYSTEM IN AN INTERCITY BUS APPLICATION

Abstract

A Vapor Absorption Refrigeration (VAR) system driven by the exhaust gas waste heat received from the internal combustion engine of an intercity bus is modeled and analyzed for air-conditioning the intercity bus cabin under different operating parameters. Initially, the hourly comfort cooling load of the intercity bus is calculated for a cooling season spanning five months between May and October in Turkey. After determining the capacity of heat source sufficiency for air-conditioning the intercity bus, energy and exergy analyses of the VAR system are conducted, then designed and compared with the vapor compression refrigeration system in respect to the effect of fuel consumption. The results show that approximately 4,489 kg/year of fuel can be saved by using the VAR system driven by an exhaust gas waste heat in an intercity bus. The maximum coefficient of performance (COP) of the VAR system is obtained as 0.78 at 5 a.m. in May, and the maximum total exergy destruction for the VAR system is obtained as 15.25 kW at 4 p.m. in July. Lastly, the specific time is selected to investigate the effect of operating and environmental parameters on the VAR system.

Keywords

• Energy,Exergy,Intercity Bus Air-Conditioning,Vapor Absorption Refrigeration System,Water-Lithium Bromide

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