Thermodynamic Analysis of Bus Air Conditioner Working with Refrigerant R600a

Abstract

Refrigerant R134a (tetrafluoroethane) is widely used in automotive air conditioners and has a good performance. However, since refrigerant R134a still has a high global warming potential (GWP), this refrigerant must be replaced with environmentally friendly refrigerants such as R600a (isobutane), which is a natural fluid, no effect on the climate, inexpensive and readily available. In this study, thermodynamic analysis of a bus air conditioner working with refrigerant R600a was performed. Adana province of Turkey was chosen as the study region. Firstly, a bus used for inter-city passenger transportation with a passenger capacity of 56 persons was selected. Cooling Load Hourly Analysis Program (HAP) was used to determine the hourly cooling load capacity of the selected inter-city bus model. Useful and reversible works of compressor, coefficient of performance (COP), exergy efficiency and exergy destructions of the bus air conditioning system were obtained and evaluated in detail.

Keywords

• Air-conditioning,refrigerant R600a,air mixing ratio,exergy,exergy efficiency,intercity bus

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