CO_2/HCs混合物宽区域黏度模型的热力学研究

Viscosity Molding of CO_2/HCs Fluid Mixtures in Wide Thermodynamic Ranges

基于Vesovic-Wakeham理论,建立CO2/HCs二元混合物黏度预测模型,对CO2/CH4,CO2/C2H6,CO2/C3H8,CO2/n-C4H10和CO2/iso-C4H10这5种重要CO2/HCs二元体系的黏度进行了预测,温度范围为273.15-973.15 K,压力范围为0.1-200 MPa,最大黏度预测值达140μPa·s。与大量文献实验数据的比较表明,所预测的黏度计算值具有较高的精度,可以满足工程应用的实际要求。

The CO2/HCs fluids are widely discussed in the engineering and scientific studies. The viscosity, as one of the most important transport properties, plays a key role in the applications of CO2/HCs mixtures in different fields. The theoretical approaches are effective to supplement the experimental viscosity data in wide thermodynamic ranges. In this paper, viscosity models are built for CO2/HCs binary mixtures based on the Vesovic-Wakeham theory. The viscosity correlations and the potential parameters of pure species are selected from literature and utilized in the constructions of models. The viscosities of five industrially important COJHCs binary systems are predicted in the temperature range from 273.15 K to 973.15 K and at the pressure up to 200 MPa. The studied systems are CO2/CH4, CO2/C2H6, CO2/C3H8, CO2/n-C4H10 and CO2/iso-C4H10. The calculated values are compared with a large amount of experimental viscosity data over a wide temperature-pressure range. The extensive analysis shows that the calculated viscosity values of the present work could be used with confidence in different industrial applications.