Air refrigeration has been extensively applied to the fields of aircraft environmental control and food refrigeration. However

these scenarios are equipped with high-pressure air sources or separate air compressors

which limits the flexible application of air refrigeration technology

and the overall coefficient of performance (COP) is low. A high-speed centrifugal compression-and-expansion integrated machine driven by a high-speed motor can considerably simplify the system and improve the COP by recovering the expansion work. This study uses a high-speed motor-driven oil-free floating bearing compression-expansion integrated machine as the core component to build a fresh-air household air-refrigeration system with an open reverse booster cycle. The temperature

pressure

and flow of the expander and compressor inlet and outlet of the system is measured

and the system is connected with an enthalpy difference chamber to obtain the refrigeration capacity and air supply parameters of the refrigeration system. Performance tests are conducted at multiple speeds under standard air-conditioning conditions. At a rated speed of 38 000 r/min

the cooling capacity is 1.6 kW. The supply-air temperature decreases and the cooling capacity increases with an increase in speed. Based on this feature

the air refrigeration system has the advantages of a direct air supply and adjustable supply-air temperature

which enables air-cooling technology in the field of fresh-air conditioning applications.