PC-SAFT方程结合重整化群理论计算R1224yd(Z)的热力学性质  

Thermodynamic Properties of R1224yd(Z)Using PC-SAFT Equation of State+Renormalization Group Theory

作　　者：赵贯甲[1] 可晋军 尹建国[1] 马素霞[1] ZHAO Guanjia;KE Jinjun;YIN Jianguo;MA Suxia(Shanxi Province Key Laboratory of Clean&High Efficient Combustion and Utilization of Circulating Fluidized Bed(Taiyuan University of Technology),Taiyuan 030024,Shanxi Province,China)

机构地区：[1]循环流化床高效清洁燃烧与利用山西省重点实验室(太原理工大学),山西省太原市030024

出　　处：《中国电机工程学报》2022年第12期4498-4504,共7页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51976132);山西省科技计划揭榜招标项目(202001101014)。

摘　　要：R1224yd(Z)作为一种氢氟烯烃(hydrofluoroolefin,HFO)类物质,具有环境友好、热力性能优良的特性,在制冷空调、高温热泵和有机朗肯循环等领域具有广泛应用前景。传统的平均场理论状态方程没有考虑密度的涨落,无法准确描述流体在临界点附近的热力学性质。基于PC-SAFT(Perturbed-Chain statistical associating fluid theory)状态方程,用重整化群理论修正Helmholtz自由能密度来考虑涨落的影响,计算了R1224yd(Z)在临界点附近和远离临界点区域的热力学性质,结果表明:相比于原始PC-SAFT方程,重整化修正使得饱和蒸气压的复现精度略有下降,但显著改善了临界点附近和远临界区域的气液平衡密度描述精度,对单相密度和气相音速也具有较高的预测精度。该模型也为R1224yd(Z)在制冷空调等领域的应用提供理论基础。Among the low global warming potential(GWP)unsaturated halocarbon refrigerants,cis-1-chloro-2,3,3,3-tetrafluoropropene(R1224yd(Z))is regarded as an alternative working fluid for R245fa in high-temperature heat pumps,centrifugal chillers and organic Rankine cycles.Although classical equations of state describe quite well the thermodynamic properties of fluids far from the critical point,they drastically fail in the near-critical region.From a microscopic point of view,the classical theory corresponds to a mean-field approximation and neglects long-range fluctuations in density for pure fluids,so it is difficult to describe the critical properties by classical equations of state.Only theories which account for these density fluctuations can provide the correct approach to the critical region.The PC-SAFT(Perturbed-Chain statistical associating fluid theory)equation of state(EOS)with the Helmholtz energy modified by renormalization group theory,which accounts for the density fluctuations,was used to predict the thermodynamic properties of R1224yd(Z)near to and far from the critical point.The results show that it has significant improvement in the representation of the phase equilibrium in the near critical point region and the saturated liquid density far from the critical point although it has a slightly poor description for vapor pressure in comparison to the PC-SAFT equation.Good results were also obtained for the single-phase density and speed of sound.This model could act as a theoretical basis for the application of R1224yd(Z).

关 键 词：PC-SAFT 状态方程 重整化群 热力学性质 R1224yd(Z) 

分 类 号：TK121[动力工程及工程热物理—工程热物理]