| 摘要 |
A closed loop refrigeration system utilizing an expansion device in the evaporation system is disclosed. In one embodiment (Fig. 1), an expansion engine (170) is connected to the evaporator inlet (164) while a compressor (175) is connected to the evaporator outlet (172). Liquid refrigerant flows through the expansion engine (170) wherein it expands and drives the expansion engine. The compressor (175) may be driven by the expansion engine (170) or by a separate motor. A control circuit adjusts the refrigerant through the control valve (174) in a manner which maintains a desired degree of superheat of the refrigerant leaving the compressor. In an alternate embodiment (Fig. 4), the evaporator system has two evaporators (54, 204). An expansion device (180) is disposed between the inlet of the first evaporator (54) and the outlet (184) of the second evaporator (204). Partially subcooled liquid refrigerant from the first evaporator (54) is passed into the second evaporator (204) through an expansion valve (186) wherein it evaporates into a gas refrigerant. Liquid refrigerant is discharged into the expansion device (180) wherein it expands and raises the energy of the gas refrigerant arriving from the second evaporator (204) into the expansion device. Liquid refrigerant from the expansion device is fed to the first evaporator (54) while the gas refrigerant is passed on to a compressor. A control circuit adjusts the flow of the refrigerant into the expansion device (180). |
