Research On Hermetic Rotary CO₂ Compressor

With the advancement of refrigerant replacement, CO2 shows great competitiveness because of its great thermophysical properties. Under this circumstance, researches around CO2 refrigeration technology get great development, especially in CO2 compressor. However, compared to some other countries, works around CO2 compressor are rather limited in China.In this paper, after analyzing and summarizing thermophysical features of CO2 and the state of the art of CO2 compressors, a new hermetic rolling piston CO2 compressor is developed. This compressor adopts a two-stage compression mechanism with intermediate cooling and the inside shell pressure is the final discharge pressure. Key parts of the compressor are analyzed in this paper.In order to comprehensively measure the performance of the developed compressor, a test stand is designed and constructed based on gas flow measument method. CO2 compressors with the cooling capacity range of 1000～6400W can be measured on this stand.After performance measurements, the developed CO2 compressor is proved to be as good as similar CO2 compressors inside the industry and has opportunities for further improvement. Besides, effects of CO2 compressor operation parameters on compressor performance are analyzed and the performance mappings of the developed compressor are also fitted.