Multiscale Modelling of Meso and Nano Scale Interfacial Dynamics Phenomena

拟议的研究方案涉及基于连续介质和分子动力学耦合的多尺度方法的开发。多尺度方法的目的是能够模拟复杂的问题，如研究受冲击波作用的材料的界面摩擦，并为长度和时间尺度范围内的分子方法提供一种细观尺度的模拟策略，其中分子方法计算昂贵，连续介质方法不够精确。研究计划包括开发用于耦合多尺度区域的混合解界面(HSI)；动态反馈耦合(DFC)策略；实施本构方程以考虑应力张量计算中的弹塑性行为；验证和验证研究；以及冲击波条件下界面动力学现象的计算研究。验证和验证研究包括将多尺度方法与以前的滑动界面分子动力学模拟和AWE提供的HE驱动的动态摩擦实验的实验数据进行比较。将对冲击波传播和滑动界面进行小型和大型模拟，以深入了解：(I)表面小部分的断裂和断裂；(Ii)表面或界面的几何形状的变化；(Iii)液化层的熔化和形成；(Iv)表面临时液化部分的凝固；(V)材料的结构变化。

The proposed research programme concerns the development of multiscale methods based on the coupling of continuum and molecular dynamics. Multiscale methods aim to enable the simulation of complex problems such as the study of interfacial friction in materials subjected to shock waves, as well as to provide a meso scale modelling strategy for the range of length and time scales, where molecular methods are computationally expensive and continuum methods are not sufficiently accurate. The research programme includes the development of hybrid solution interface (HSI) for coupling multiscale domains; a dynamic-feedback coupling (DFC) strategy; implementation of constitutive equation to account for the elastic-plastic behaviour in the stress-tensor calculation; verification and validation studies; and computational studies of interfacial dynamics phenomena under shock wave conditions. The verification and validation studies include comparisons of the multiscale methods against previous molecular dynamic simulations for sliding interfaces and experimental data from HE-driven dynamic-friction experiments provided by AWE. Both small and large scale simulations of shock wave propagation and sliding interfaces will be carried out to gain insight into: (i) fracture and breaking of small parts of the surface; (ii) change of the geometrical shape of the surface or interface; (iii) melting and formation of a liquid layer; (iv) solidification of temporarily liquefied parts of the surface; (v) structural changes in the materials.