Cold fluid circulation device includes two-step compressor with two compression mechanisms and inlet pressure determination system to manage pressure of cooling fluid

摘要

The cold fluid circulation device comprises a two-step compressor (14) that has a first compression mechanism (19) and a second compression mechanism (20). It has a physical size with a correlation to an inlet pressure (Ps) of the cold fluid that is sucked in from the two-step compressor and evaluated by an inlet pressure determination system (23, 25, 26). If the determination value (Tam, Twi, Te) from the inlet pressure determination system is similar or higher than the pre-defined value (TamA, TwiA, TeA), a higher pressure (Pd) of the two-step compressor is achieved in order that the mid pressure (Pm) of the middle pressure cooling fluid in the compressor is lower than the predefined value.