›› 2014, Vol. 23 ›› Issue (12): 125101-125101.doi: 10.1088/1674-1056/23/12/125101

• PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES • 上一篇    下一篇

Modified 2CLJDQP model and the second virial coefficients for linear molecules

张颖, 王升, 何茂刚   

  1. Key Laboratory of Thermo-Fluid Science and Engineering, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
  • 收稿日期:2014-01-13 修回日期:2014-06-03 出版日期:2014-12-15 发布日期:2014-12-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 51106129) and the Fundamental Research Funds for the Central University, China (Grant No. XJTU-HRT-002).

Modified 2CLJDQP model and the second virial coefficients for linear molecules

Zhang Ying (张颖), Wang Sheng (王升), He Mao-Gang (何茂刚)   

  1. Key Laboratory of Thermo-Fluid Science and Engineering, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
  • Received:2014-01-13 Revised:2014-06-03 Online:2014-12-15 Published:2014-12-15
  • Contact: He Mao-Gang E-mail:mghe@mail.xjtu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 51106129) and the Fundamental Research Funds for the Central University, China (Grant No. XJTU-HRT-002).

摘要: A modified form of 2CLJDQP potential model is proposed to calculate the second virial coefficients of two-center Lennard-Jones molecules. In the presented potential model, the potential parameters σ and ε are considered as the temperature-dependent parameters in the form of hyperbolical temperature function based on the theory of temperature-dependent potential parameters. With this modified model, the second virial coefficients of some homonuclear molecules (such as O2, Cl2, CH3CH3, and CF3CF3) and heteronuclear molecules (such as CO, NO, CH3F, CH3Cl, CH3CF3, CH3CHF2, and CF3CH2F) are calculated. Then the Lorentz–Berthelot mixing rule is modified with a temperature-dependent expression, and the second virial coefficients of the heteronuclear molecules (such as CH3F, CH3Cl, and CH3CF3) are calculated. Moreover, CO2 and N2O are also studied with the modified 3CLJDQP model. The calculated results from the modified 2CLJDQP model accord better with the experimental data than those from the original model. It is shown that the presented model improves the positive deviation in low temperature range and negative deviation in high temperature range. So the modified 2CLJDQP potential model with the temperature-dependent parameters can be employed satisfactorily in large temperature range.

关键词: potential function, temperature-dependent parameters, linear molecules, second virial coefficients

Abstract: A modified form of 2CLJDQP potential model is proposed to calculate the second virial coefficients of two-center Lennard-Jones molecules. In the presented potential model, the potential parameters σ and ε are considered as the temperature-dependent parameters in the form of hyperbolical temperature function based on the theory of temperature-dependent potential parameters. With this modified model, the second virial coefficients of some homonuclear molecules (such as O2, Cl2, CH3CH3, and CF3CF3) and heteronuclear molecules (such as CO, NO, CH3F, CH3Cl, CH3CF3, CH3CHF2, and CF3CH2F) are calculated. Then the Lorentz–Berthelot mixing rule is modified with a temperature-dependent expression, and the second virial coefficients of the heteronuclear molecules (such as CH3F, CH3Cl, and CH3CF3) are calculated. Moreover, CO2 and N2O are also studied with the modified 3CLJDQP model. The calculated results from the modified 2CLJDQP model accord better with the experimental data than those from the original model. It is shown that the presented model improves the positive deviation in low temperature range and negative deviation in high temperature range. So the modified 2CLJDQP potential model with the temperature-dependent parameters can be employed satisfactorily in large temperature range.

Key words: potential function, temperature-dependent parameters, linear molecules, second virial coefficients

中图分类号:  (Thermodynamic properties, equations of state)

  • 51.30.+i
34.20.-b (Interatomic and intermolecular potentials and forces, potential energy surfaces for collisions) 51.10.+y (Kinetic and transport theory of gases) 34.20.-b (Interatomic and intermolecular potentials and forces, potential energy surfaces for collisions)