Effect of Refrigerant Charge, Compressor Speed and Air Flow Through the Evaporator on the Performance of an Automotive Air Conditioning System

Using identical mechanical hardware used in an automobile, a stationary test bench has been developed for an automotive air conditioning system (AACS). However, a number of additional sensors have been used in the system for an accurate assessment of its performance. The steady state performance of the system has been investigated for three independent variables, namely the refrigerant charge level, the compressor speed and the speed of the evaporator fan. Tests have been planned to estimate the performance of the individual components and to determine a non-dimensional rating parameter to describe condenser performance. While the refrigerant flow rate is influenced primarily by refrigerant charge level and compressor speed, the COP and cooling capacity depends on all the three operating variables. The optimum operating condition with compressor and blower speed along with refrigerant charge level has also been identified.