Determination of the ejector dimensions used in bus air conditioning systems according to various parameters

Ejector cooling systems is an area that is being investigated by researchers for many years. In this study; thermodynamic analysis of current vapor compression refrigeration cycle used in buses and new vapor compression refrigeration cycle with two phase ejector and two evaporators is made. Dimensions of ejector used in ejector refrigeration cycle are determined and changes in dimensions are investigated according to various parameters. Air conditioning systems which are used in buses have increased cooling efficiency about 15 percent just by adding two phase ejector into the system according to the obtained results. The total length of the ejector according to operating conditions determined by considering Mediterranean climate zone is estimated to be approximately 793mm in a bus air conditioning system which has 32kW cooling capacity. It also has been seen that nozzle, mixing section and diffuser efficiencies, condenser and primary evaporator temperatures are the most effective parameters in calculation of the total length of the ejector.