Brownian dynamics simulations of linear polymers under shear flow
Brownian dynamics simulations of linear polymers under shear flow
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剪切流下线性聚合物的布朗动力学模拟
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
G. Davies
中科院分区：
文献类型：
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作者：
A. Lyulin;D. Adolf;G. Davies
用布朗动力学方法模拟了剪切流作用下三种不同模型描述的高分子链。模型A是由刚性杆连接的珠子组成的自由连接的Kramers链。模型B是一个自由连接链，由可伸长的非线性弹性（FENE）弹簧组成。这两个模型都没有考虑排除体积和流体动力学相互作用。模型C是具有刚性键、价、扭角势、排斥体积和流体动力学相互作用的链。相应地，得到了模型A和B在大剪切速率γ下特性粘度[η]的渐近依赖性[η]<$γ−1/3和[η]<$γ−2/3。第一正应力系数<$1 <$γ−4/3的渐近相关性与模型的具体选择无关。在中等剪切速率下，所有模型均遵循[η]<$γ−1/2。研究了分子量对流变性能的标度依赖性。结果的模拟…
Brownian dynamics simulations of a polymer chain described by three different models under the influence of a shear flow have been performed. Model A is a freely jointed Kramers chain consisting of beads connected by rigid rods. Model B is a freely jointed chain consisting of finitely extensible nonlinear elastic (FENE) springs. Excluded volume and hydrodynamic interactions are not taken into account in either of these two models. Model C is a chain with rigid bonds, valence, and torsional angle potentials, excluded volume and hydrodynamic interactions. Asymptotic dependencies [η]∼γ−1/3 and [η]∼γ−2/3 for the intrinsic viscosity [η] at large shear rates γ for models A and B, correspondingly, have been obtained. Asymptotic dependencies for the first normal stress coefficient Ψ1∼γ−4/3 do not depend on the particular choice of model. At intermediate shear rates [η]∼γ−1/2 is followed for all models. Scaling dependencies of rheological properties on molecular weight have been studied. Results of the simula...