Optimal operating conditions for an electric ECS in ground parking status

The Electric Environmental Control System (EECS), which uses an electric compressor to draw in outside air instead of the engine bleed, is under consideration. In this study, the case of EECS operating in a grounded parking status is discussed. The pressure ratios for the electric compressor and the air cycle machine compressor are set as variable parameters. A thermodynamic analysis is performed to clarify the operating conditions of the system, taking dehumidification into account. The coefficient of performance is obtained, and it is found that the maximum value is obtained under the condition where the pressure ratio of the electric compressor is the smallest.