Small compressors for transcritical CO{sub}2 applications

摘要

CO{sub}2 is investigated as one of the future refrigerants, as it can be applied in vapour compression processes, is not flammable or toxic and environmentally benign. Therefore, there is a potential that CO{sub}2 is used in suitable applications, where today's system's efficiency could at least be met at comparable investments or initial system costs. The compressor of a refrigerant compression process is the component with the major influence on the efficiency and reliability of the entire system. Due to the fluid properties of CO{sub}2, the pressure ratio of the refrigeration process is compared to common refrigeration process is compared to common refrigeration processes rather low while the pressure difference is extremely high. In the paper the effects on the efficiency of CO{sub}2-compressor are evaluated and a promising design concept for an efficient CO{sub}2-compressor was derived under the perspective to minimize its refrigeration capacity.