摘要
使用基于COMPASS力场的分子动力学(MD)模拟方法计算了CO2在气相、液相以及超临界区的自扩散系数。计算结果表明温度对扩散系数的影响在密度较低时比较明显,随着密度的升高温度的影响逐渐减弱;密度较高时密度的影响对扩散系数起主导作用。通过研究温度和密度对扩散系数的影响规律,提出了预测CO2自扩散系数的新方程,该方程与模拟值和文献试验值吻合良好。
Molecular dynamics （MD） simulation based on COMPASS force field was applied to investigate the diffusivity of pure CO2 system through different phases. The influences of temperature and density on diffusivity were investigated. The density was the dominant factor for high density state, while the influence of temperature became more important with the decrease of density. Based on the results, a new equation was established to predict the self-diffusion coefficients of CO2, the equation agreed well with the simulation and experimental data in literature in a wide range of density.
出处
《化学工业与工程》
CAS
2009年第1期57-61,共5页
Chemical Industry and Engineering
