摘要
Aiming at solving the problem of high global warming potential of R134 a,a new mixed refrigerant R13 I1/R152 a(molar fraction ratio of 35:65)with no ozone depletion potential and low global warming potential was proposed as a substitute for R134 a in automotive air conditioning.The computational models for the thermodynamic properties of R13 I1/R152 a were established by using the PR(Peng-Robinson)equation of state combined with the vdW mixing rule.Based on these models,the cycle performance of this working fluid was calculated,which was also compared with that of R134 a and R1234 yf under the different operating conditions.The results show that R13 I1/R152 a is a near azeotropic refrigerant whose temperature glide is approximately 0,and the saturated vapor pressure curve of which is equivalent to that of R134 a.Moreover,compared to R134 a,R13 I1/R152 a has an average 5.7%improvement in coefficient of performance as well as similar volumetric cooling capacity.The average coefficient of performance and volumetric cooling capacity of R13 I1/R152 a are significantly higher than those of R1234 yf by 13.8%and12.0%,respectively.However,the average discharge temperature of R13 I1/R152 a is approximately13.3 K higher than that of R134 a,but it is also within reasonable limits.Hence,the application of the proposed refrigerant R13 I1/R152 a in automotive air conditioning system is technically feasible.
基金
supported by the National Natural Science Foundation of China(22068024)。