RESEARCH AND DEVELOPMENT OF FREE PISTON EXPANDERS FOR TRANSCRITICAL CO2 REFRIGERATION CYCLE
This paper presents the design and experimental validation of the free piston expanders for transcritical CO2 refrigeration cycle. A novel slider-based control scheme is put forward to control the expander inlet/outlet. The prototype expanders of the single acting and double acting type are developed successively, which are then experimentally validated using air or CO2 as working fluid in different working conditions. The experimental results show that the double acting free piston expander can work more steadily in much wider range of pressure difference than the single acting type, and its frequency is approximately linear with the pressure difference through the expander. For the double acting free piston expander operating in the air system, the optimal frequency exists in the range of 10Hz to 17Hz, and the isentropic efficiency is estimated to be about 62％ at the high/low pressures of 0.78MPa and 0.33MPa respectively. Further research of the double acting free piston expander is ongoing in the CO2 cycles.
B LIU B ZHANG X PENG P SHU
National Engineering Research Center for Fluid Machinery and Compressors Xi’an Jiaotong University, Xi’an, 710049, P.R. China
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21（万方平台首次上网日期，不代表论文的发表时间）