Postdoc: Modeling Fluids Under Confinement and Shear

本项目将使用非平衡分子动力学技术研究受限薄膜的润滑行为。特别是，支链烷烃和线性烷烃与酯杂质的混合物将被研究。目的是了解杂质对诸如广义剪切粘度和流体动力边界条件等性质的影响。复杂的长距离静电和金属流体相互作用，加上必然的大系统尺寸，提出了一个重大的计算挑战，这将需要有效地使用大规模并行计算设施。现有算法和其他正在开发的算法使用Nose-Hoover链和外部场在选定温度下建立所需的速度分布。此外，线性响应理论可以很容易地应用于建立现象学性质之间的联系，例如Navier-Stokes方程和分子描述。

This project will study the lubrication behavior of confined thin films using non-equilibrium molecular dynamics techniques. In particular, mixtures of branched and linear alkanes with ester impurities will be studied. The goal is to understand the effect of the impurities on properties such as the generalized shear viscosity and hydrodynamic boundary conditions. Complicated long ranged electrostatic and metal-fluid interactions, plus necessarily large system sizes, present a significant computational challenge that will require efficient use of massively parallel computing facilities. Existing algorithms and others currently under development employ Nose-Hoover chains and external fields to establish the desired velocity profile at the chosen temperature. Furthermore, linear response theory can readily be applied to make the connection between phenomenological properties, such as the Navier-Stokes equation, and molecular descriptions.