Müller-Plathe F
Max-Planck-Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz, Germany.
Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 1999 May;59(5 Pt A):4894-8. doi: 10.1103/physreve.59.4894.
A nonequilibrium method for calculating the shear viscosity is presented. It reverses the cause-and-effect picture customarily used in nonequilibrium molecular dynamics: the effect, the momentum flux or stress, is imposed, whereas the cause, the velocity gradient or shear rate, is obtained from the simulation. It differs from other Norton-ensemble methods by the way in which the steady-state momentum flux is maintained. This method involves a simple exchange of particle momenta, which is easy to implement. Moreover, it can be made to conserve the total energy as well as the total linear momentum, so no coupling to an external temperature bath is needed. The resulting raw data, the velocity profile, is a robust and rapidly converging property. The method is tested on the Lennard-Jones fluid near its triple point. It yields a viscosity of 3.2-3.3, in Lennard-Jones reduced units, in agreement with literature results.
提出了一种用于计算剪切粘度的非平衡方法。它颠倒了非平衡分子动力学中通常使用的因果关系图景：施加的是效应，即动量通量或应力，而原因，即速度梯度或剪切速率，则从模拟中获得。它与其他诺顿系综方法的不同之处在于维持稳态动量通量的方式。该方法涉及粒子动量的简单交换，易于实现。此外，它可以做到守恒总能量以及总线性动量，因此无需与外部温度浴耦合。所得的原始数据，即速度分布，是一种稳健且快速收敛的性质。该方法在靠近其三相点的 Lennard-Jones 流体上进行了测试。在 Lennard-Jones 约化单位下，它得出的粘度为 3.2 - 3.3，与文献结果一致。
