The refrigerant in the refrigeration system is directly output and evaporated into the target control element (heat exchanger) for heat exchange, thereby cooling the target control object. Compared with the fluid (gas) transported into the heat exchanger, it has a higher heat exchange capacity, which is especially suitable for applications where the heat exchange area of the heat exchanger is small but the heat exchange capacity is large. It can also be used as gas capture, the refrigerant is directly passed into the trap to evaporate, and the gas in the space is quickly captured through the condensation effect on the surface of the trap.