CO2, Performance measure, Test facility, Transcritical cycle, Subcritical cycle
Due to the transcritical nature, some of the test methods used in the conventional subcritical refrigeration cycle, such as the liquid refrigerant flow metering method and the water-cooled condenser metering method, are no longer appropriate for evaluating the transcritical carbon dioxide (CO2) compressor performances. This paper introduces a performance test facility taken into account both the transcritical and the subcritical operating conditions for CO2 compressor, including design requirements and parameter control, the main technical challenges and solutions in the laboratory testing facility development. The compressor refrigerating capacity major test results with this setup are compared to the auxiliary test and found less than 4% discrepancies. In addition, this test facility has high test repeatability. Due to these advantages, it is being used to provide experimental data and technical support for the new China National Standard (GB) "Positive Displacement CO2 Refrigerant Compressor Unit".