R1234ze(E)替代R134a对二级压缩循环离心压缩机及制冷性能的影响

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关键词：制冷剂替代；二级压缩循环；离心压缩机；制冷性能中图分类号：TB652；O354文献标志码：ADOI：10.7652/xjtuxb202509014 文章编号：0253-987X（2025）09-0142-10

The Effects of R1234ze（E） Replacing R134a on the Two-Stage Compression Cycle Centrifugal Compressor and Refrigeration Performance

LIU dan1，XI Guang1，DUAN Yafei1，CHEN Han1，WANG Zhiheng1 ， LI Zhenshan²，LIU Zhiyuan² （1.School of Energy and Power Engineering，Xi'an Jiaotong University，Xi’an 71oo49，China; 2. Chongqing Midea General Refrigeration Equipment Co.，Ltd.，Chongqing 40l336，China）

Abstract： To investigate the changes in the performance of centrifugal compressors and refrigeration eficiency after the replacement of refrigerant Rl34a with Rl234ze（E），this study establishes a mathematical model of the refrigeration cycle and a flow model of a two-stage series centrifugal compressor based on a two-stage vapor compression refrigeration cycle with incomplete cooling between two throtling processes （VCS-TS-FT）. The influence of the replacement of Rl34a with （204号 R1234ze （E） on compressor and system performance is analyzed in detail. Numerical results show that，after replacing R134a ，under the same condensing temperature and unchanged rotational speed，R1234ze（E）achieves 83.7% of Rl34a’s cooling capacity，with a 2% higher pressure ratio，nearly unchanged efficiency， 0.5% lower discharge temperature，11. 6% lower shaft power，and a decrease in coefficient of performance （ ξcop ） from 6.83 to 6.59. Adjusting the compressor speed significantly alters the performance of the compressor and refrigeration cycle. A 7% increase in speed results in a refrigeration capacity of R1234ze（E） equal to that of Rl34a at the designed speed， but the compressor efficiency decreases by 5.9% ，and the system ξcop drops to 6.15.Conversely，a 3.4% decrease in speed with unchanged compressor volumetric flow results in the refrigeration capacity of R1234ze（E） being reduced to 76% of that of R134a at the designed speed，while the system ξcop rises to 6.87. Therefore，the direct replacement of Rl34a with （20号 R1234ze（E） without redesigning the compressor cannot achieve equivalent levels of both ξcop and refrigeration capacity compared to R134a . Additionally，improvements to the condenser and evaporator are required to achieve the same refrigeration capacity.

Keywords： refrigerant replacement；two-stage compression cycle； centrifugal compressor;refrigeration performance

离心式冷水机组在大型建筑空调系统中扮演着十分重要的角色[1]，自21世纪初期至今，R134a制冷剂已使用很多年，但其全球变暖潜值（GWP）高达1430，对温室效应影响较大[2]。（剩余14055字）