| 摘要 |
Refrigerant is circulated through a vapor compression system including a compressor, a gas cooler, an expansion device, and an evaporator. Preferably, carbon dioxide is used as the refrigerant. The expansion device is a work recovery device which extracts energy from the expansion process and is coupled with a fluid pumping device that cools the refrigerant flowing through the gas cooler. The fluid pumping device pumps fluid through the gas cooler at a flow rate related to the energy extracted from the expansion process. The system provides a self-controlling mechanism to regulate the pressure in the gas cooler. If the pressure in the gas cooler increases, more energy is extracted from the expansion process, increasing the flowrate of the fluid pumping device, and decreasing the pressure of the refrigerant in the gas cooler. If the pressure in the gas cooler decreases, less energy is extracted from the expansion process, decreasing the flowrate of the fluid pumping device, and increasing the pressure of the refrigerant in the gas cooler. |
