| High-power electrical equipments have been applied on the aircraft, which results in the heating loads increasing up to dozens of kilowatt. Comparing to the traditional air cycle system (ACS),the vapor cycle system (VCS) needs lower engine bleed and has larger refrigeration capacity, which has attracted more and more people are concerned about it. In this dissertation, the aircraft VCS has been investigated using numerical method. The results and conclusions are described briefly as follows:(1) Several refrigerant thermodynamics parameters are modeled based on Martin-Hou state equations, and several numerical modules are constructed using Matlab/Simulink technique. The refrigerant R134a has been employed to validate these numerical modules. Furthermore, the refrigerant module library has been established.(2) The commercial software Flowmaster has been used to establish the steady-state testing modules of the evaporator and condenser, which are also compared to the previous results. Results show that this software can estimate the heat transfer characteristics of evaporator and condenser. Moreover, it can capture the phase transition position, which indicates that the software Flowmaster can be used to investigate the VCS.(3) The simplified VCS has been modeled, and has been analyzed in the steady and unsteady state. Results can provide some guidance about the structure optimization of the evaporator and condenser. Several numerical cases have been made, which can exhibit the dynamics performance of this simplified VCS, and give some ideas for the engineering. Keywords: vapor cycle system, refrigerant, numerical simulation, evaporator, condenser.
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