论文标题
简单流体中的剪切和散装加速度粘度
Shear and bulk acceleration viscosities in simple fluids
论文作者
论文摘要
移动流体的速度场中的不均匀性被系统的固有粘性行为抑制。与速度场的差异和卷曲有关的体积和剪切效应都是相关的。在分子时间尺度上，除了Navier-Stokes描述之外，记忆起着重要的作用。我们在这里根据分子和过度阻尼的布朗动力学多体模拟证明了类似粘性对加速场作用的作用。这种加速粘性行为与加速场的差异和卷曲有关，可以使用简单的指数衰减的内存核进行定量描述。同时使用速度和加速度场可以描述分子尺度上的快速动力学。
Inhomogeneities in the velocity field of a moving fluid are dampened by the inherent viscous behaviour of the system. Both bulk and shear effects, related to the divergence and the curl of the velocity field, are relevant. On molecular time scales, beyond the Navier-Stokes description, memory plays an important role. We demonstrate here on the basis of molecular and overdamped Brownian dynamics many-body simulations that analogous viscous effects act on the acceleration field. This acceleration viscous behaviour is associated with the divergence and the curl of the acceleration field and it can be quantitatively described using simple exponentially decaying memory kernels. The simultaneous use of velocity and acceleration fields enables the description of fast dynamics on molecular scales.
