论文部分内容阅读
醇类、水、氨等流体在工业上有着广泛的应用,但由于氢键作用形成分子缔合,使用简单状态方程难以精确描述其热力学性质;而在近临界区,由于浓度涨落的长程关联,使其描述则更为困难。该文在CPA(cubic plus association)状态方程的基础上,用重整化群理论修正Helmholtz自由能来考虑涨落的影响,计算了甲醇、水和氨在近临界和远离临界点区域的p-ρ-T性质。结果表明:该方法显著改善了临界参数和近临界区的气液相平衡数据的描述情况,在单相区的预测精度也较高,适用于缔合流体热力学性质的研究。
Liquids such as alcohols, water and ammonia are widely used in industry. However, due to the formation of molecular association by hydrogen bonding, it is difficult to accurately describe their thermodynamic properties using the simple equation of state. In the near-critical region, due to long-range correlation of concentration fluctuation, , Making it more difficult to describe. Based on the state equation of cubic plus association (CPA), the effects of fluctuations on Helmholtz’s free energy are revisited using the renormalization group theory. The effects of methanol, water and ammonia on the near-critical and p- ρ-T nature. The results show that this method can remarkably improve the description of the critical parameters and the gas-liquid equilibrium data in the near-critical region. The prediction accuracy of the single-phase region is also high, which is suitable for the study of the thermodynamic properties of the associated fluids.