Figure 6 shows the cooling COP and cooling capacity of the electrical air conditioning system with
the variations of the inlet air conditions of the evaporator. The cooling COP and the cooling capacity
averagely increased slightly with the rise of the evaporator inlet air temperatures from 27.0 °C to
35.0 °C. This is because the cooling capacity increased to match the cooling loads for the cabin and the
specific refrigerating effect in the evaporator is also increased. However, at the gas cooler inlet
pressure of 92.0 bar, the cooling COP and the cooling capacity decreased slightly with rise of the
evaporator inlet air temperatures from 27.0 °C to 35.0 °C. In addition, the increased amount of cooling
capacity was greater than that of the cooling COP because the compressor works increased due to the
increased refrigerant mass flow rate. Figure 6b shows effects of the inlet air flow rate of the evaporator
on the cooling COP and cooling capacity according to gas cooler inlet pressure. The cooling COP and
the cooling capacity were increased with the rise of the evaporator inlet air flow rate from 4.0 m3/min
to 7.0 m3/min due to the increased heat transfer efficiency of the evaporator. Therefore, the variation of
the evaporator inlet air flow rate had a slightly more effect on the cooling capacity and cooling COP of
the tested system than the variation of the evaporator inlet air temperature did.