Computation of thermodynamic and transport properties to predict thermophoretic effects in an argon-krypton mixture.
Computation of thermodynamic and transport properties to predict thermophoretic effects in an argon-krypton mixture.
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计算热力学和输运特性以预测氩氪混合物中的热泳效应。
DOI：
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发表时间：
2013
影响因子：
4.4
通讯作者：
B. D. Todd
中科院分区：
文献类型：
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作者：
N. Miller;P. Daivis;I. Snook;B. D. Todd
热浸作用是由温度梯度引起的分子运动。本文报道了利用非平衡分子动力学模拟在恒温壁上受控于两种不同温度的Ar-Kr流体的热电泳性的研究结果。得到的壁面之间的温度分布与索雷特系数一起用于预测整个通道内形成的浓度分布。我们通过计算互扩散系数和热扩散系数来得到Soret系数。利用格林-久保积分和由平衡分子动力学模拟得到的径向分布函数，我们提出了一种计算二元体系输运系数的合适方法。我们的方法具有独特的优点，可以分离互扩散系数和热扩散系数，并计算它们对二元混合物中的热电泳性的各自贡献的符号和大小。
Thermophoresis is the movement of molecules caused by a temperature gradient. Here we report the results of a study of thermophoresis using non-equilibrium molecular dynamics simulations of a confined argon-krypton fluid subject to two different temperatures at thermostated walls. The resulting temperature profile between the walls is used along with the Soret coefficient to predict the concentration profile that develops across the channel. We obtain the Soret coefficient by calculating the mutual diffusion and thermal diffusion coefficients. We report an appropriate method for calculating the transport coefficients for binary systems, using the Green-Kubo integrals and radial distribution functions obtained from equilibrium molecular dynamics simulations of the bulk fluid. Our method has the unique advantage of separating the mutual diffusion and thermal diffusion coefficients, and calculating the sign and magnitude of their individual contributions to thermophoresis in binary mixtures.