Laboratoire des Fluides Complexes (UPPA-CNRS-TOTAL), Pau University, BP 1155, 64013 Pau Cedex, France.
J Chem Phys. 2011 Feb 14;134(6):064505. doi: 10.1063/1.3553262.
In this work, we have tested the efficiency of two scaling approaches aiming at relating shear viscosity to a single thermodynamic quantity in dense fluids, namely the excess entropy and the thermodynamic scaling methods. Using accurate databases, we have applied these approaches first to a model fluid, the flexible Lennard-Jones chain fluid (from the monomer to the hexadecamer), then to real fluids, such as argon and normal alkanes. To enlarge noticeably the range of thermodynamics conditions for which these scaling methods are applicable, we have shown that the use of the residual viscosity instead of the total viscosity is preferable in the scaling procedures. It has been found that both approaches, using the adequate scaling, are suitable for the Lennard-Jones chain fluid model for a wide range of thermodynamic conditions whatever the chain length when scaling law exponents and prefactors are adjusted for each chain length. Furthermore, these results were found to be well respected by the corresponding real fluids.
在这项工作中，我们测试了两种缩放方法的效率，旨在将剪切黏度与密集流体中的单个热力学量相关联，即过剩熵和热力学缩放方法。我们使用精确的数据库，首先将这些方法应用于模型流体，即柔性 Lennard-Jones 链流体（从单体到十六聚体），然后应用于真实流体，如氩气和正烷烃。为了显著扩大这些缩放方法适用的热力学条件范围，我们表明在缩放过程中，使用剩余黏度而不是总黏度是优选的。结果表明，在调整每个链长的缩放律指数和前因子时，这两种方法都适用于广泛的热力学条件下的 Lennard-Jones 链流体模型，无论链长如何。此外，这些结果被发现与相应的真实流体很好地吻合。
