The phase-change refrigeration system of cascade pump-compressor is aimed at high heat flux components heat radiation cooling technology.The characteristics of starting and stable operation and the adaptability on high-temperature environment are investigated in this paper.The results show that at the first stage of the mechanical pump starting

because of the flow characteristics of the refrigerant and the inlet suction effect

the pressure increased firstly and then decreased.At the start time of the heat source

less pressure and temperature fluctuations

heat source starts stably.At stable operation stage

not only the flow rate of system increases from 2.22 g·s-1 to 5.56 g·s-1

but also the dryness of the evaporator' outlet declines

pressure drop of the evaporator' outlet increases and the surface temperature of evaporator declines.In the high temperature environment

the refrigeration system can meet the demand of the cooling requirement of heat source

and the fluctuation of pressure and outlet temperature rises.