Comment on: Nonequilibrium molecular dynamics calculation of self‐diffusion in a non‐Newtonian fluid subject to a Couette strain field
Comment on: Nonequilibrium molecular dynamics calculation of self‐diffusion in a non‐Newtonian fluid subject to a Couette strain field
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评论：受库埃特应变场影响的非牛顿流体中自扩散的非平衡分子动力学计算
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
K. Fraser
中科院分区：
文献类型：
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作者：
P. Cummings;B. Y. Wang;D. Evans;K. Fraser
为了研究剪切应力存在下的扩散性质，对非牛顿体系中的简单流体进行了分子动力学模拟。非平衡分子动力学 (NEMD) sllod 算法用于生成均匀边界驱动的库埃特流。扩散系数张量的元素通过三种不同的途径进行评估：通过爱因斯坦与分子位移张量的相应元素的关系，通过涉及动量自相关函数和互相关函数张量的Green-Kubo表达式，以及利用NEMD色场方法。扩散系数张量的所有三种途径都显示出一致的结果。模拟研究中使用了处于三相点的简单球对称伦纳德-琼斯流体。我们发现，在应变率足够大的库埃特应变场中，各个方向的扩散都大大增强。我们提出并验证了一个新的...
Molecular dynamics simulations have been performed on a simple fluid in the non‐Newtonian regime in order to study the nature of diffusion in the presence of shear stress. The nonequilibrium molecular dynamics (NEMD) sllod algorithm is used to generate a homogeneous boundary driven Couette flow. The elements of the tensor of diffusion coefficients have been evaluated by three different routes: through Einstein relations with the corresponding elements of the tensor of molecule displacements, through Green–Kubo expressions involving tensor of momentum autocorrelation functions and cross‐correlation functions, and by utilizing an NEMD color field method. All three routes to the tensor of diffusion coefficients are shown to yield consistent results. A simple spherically symmetric Lennard‐Jones fluid at its triple point was used in the simulation study. We find that in a Couette strain field of sufficiently large strain rate, diffusion in all directions is enhanced substantially. We propose and verify a new a...