基于亥姆霍兹自由能的实际气体状态方程  

Equation of State for Real Gases Based on Helmholtz Free Energy

作　　者：齐超 刘拓 易满满 QI Chao;LIU Tuo;YI Manman

机构地区：[1]西安航天动力研究所,西安市710100 [2]西安航天远征流体控制股份有限公司,西安市710100 [3]北京电子工程总体研究所

出　　处：《化工装备技术》2022年第4期21-25,共5页Chemical Equipment Technology

摘　　要：气体状态方程是表征气体温度、压力、密度等关系的函数,通过两个独立参数可以计算其余的物性参数。气体状态方程是石油、化工、航空航天等工业相关系统设计的重要基础。以氮气为介质,介绍了理想气体状态方程和实际气体状态方程,包括范德瓦尔斯方程、Redlich-Kwong方程以及基于亥姆霍兹自由能的Span方程。以美国国家标准与技术研究院(NIST)的氮气物性数据为标准,对上述几种状态方程进行了比较,结果表明Span方程的计算结果和标准值吻合最好,平均偏差为0.11%,远小于理想气体状态方程和立方型气体状态方程。因此在相关系统设计时推荐使用基于亥姆霍兹自由能的Span状态方程。The gas state equation was a function that characterizes the relationship between gas temperature,pressure, density, etc. The remaining physical parameters could be calculated through two independent parameters.The gas equation of state was an important basis for the design of related systems in petroleum, chemical, aerospace and other industries. Using nitrogen as the medium, the ideal gas equation of state and the actual gas equation of state were introduced, including the Van der Waals equation, the Redlich-Kwong equation and the Span equation based on Helmholtz free energy. The above equations of state were compared with the nitrogen physical property data of the National Institute of Standards and Technology(NIST) as the standard. The results showed that the calculated results of the Span equation were in good agreement with the standard values, and the average deviation was 0.11%, which was much smaller than that of the ideal gas equation of state and the cubic gas equation of state.Therefore, it was recommended to use the Span equation of state based on Helmholtz free energy when designing the relevant system.

关 键 词：气体状态方程 亥姆霍兹自由能 氮气 计算精度 

分 类 号：TQ019[化学工程]