REFRIGERATION SYSTEM

摘要

A low pressure in a refrigeration cycle and a refrigerant temperature at the outlet of a radiator under reference operating conditions are a reference low pressure and a reference refrigerant temperature, respectively, and a high pressure in a refrigeration cycle where the coefficient of performance of the refrigeration cycle becomes highest under reference operating conditions is a reference high pressure. Assuming the density of saturated gas refrigerant under the reference low pressure is rho1, the density of refrigerant under the reference high pressure and reference refrigerant temperature is rho2, the density of refrigerant under the reference high pressure and reference refrigerant temperature expanded adiabatically up to the reference low pressure is rho3, the volume of the compression chamber of a compressor immediately after being shut off from the suction side is v1, and the rotation speed ratio of the compressor to that of an expansion machine is r, the volume v2 of a first fluid chamber (72) in the expansion machine (60) immediately after being shut off from the inflow side is set such that v2=rho1.v1.r/rho2, and the volume v3 of a second fluid chamber (82) immediately before communicating with the outflow side is set such that v3=rho2.v2/rho3.