This paper presents the structure of a new system, which can efficiently separate therefrigerant mixture and vary the composition inside the circuit to adjust the capacities ofthe system with load changes. A dynamic and distributed model is developed to analyzethe dynamic characteristics in the course of variation of composition. It is shown there aresome optimizing design parameters for the new system. If the system designed by optimizingparameters, it will be effective to adjust the composition in the system. This paper presents the structure of a new system, which can distinct separate therefrigerant mixture and vary the composition inside the circuit to adjust the capacities of the system with load changes. A dynamic and distributed model is developed to analyzethe dynamic characteristics in the course of variation of It is shown there aresome optimizing design parameters for the new system. If the system designed by optimizingparameters, it will be effective to adjust the composition in the system.