主 办：爆炸科学与技术国家重点实验室
安全与防护协同创新中心
报告题目：The development of a Coarse Graining Framework for Large Scale Granular Systems from a Multi-scale Modelling Perspective
报告人：Prof. Yuntian Feng
Swansea University, UK.
时间：2019年9月18日下午14:30
地点：北京理工大学3号教学楼146会议室
报告人简介：
Dr Feng is a Professor in Zienkiewicz Centre for Computational Engineering, Swansea University, UK. The Centre has a long established international reputation in computational engineering research and particularly has pioneered the development of many of the cornerstones of the finite element method. With a first degree in Mechanical Engineering and a PhD in Computational Mechanics, Prof. Feng has been working in the Centre since 1992. He has been intensively involved in high quality research activities in many aspects of Computational Engineering and is a renowned expert. Over the last 20 years, his main research interests have been focused on developing advanced computational techniques for modelling multi-fracturing of solids and particulate systems under dynamic/impact loading. In particular, he has made original contributions to many fundamental developments in the discrete element method, and is an international authority in the field. Prof. Feng has published over 200 research papers, and has delivered over 10 plenary and keynote lectures in international conferences. His current research projects include the development of general energy conserving contact theories for arbitrarily shaped non-spherical discrete elements, a generic computational framework for coarse-graining modelling of large scale particulate systems, and multi-phase and multi-field coupling strategies for granular systems.
报告摘要：
Huge computational costs associated with discrete element modelling of large scale particle systems have been one of the major factors that still hinder the application of DEM to industrial scale problems. Coarse graining and multi-scale modelling, together with high performing computing platforms, are possible approaches to achieving such a goal.
In the current coarse graining framework, in addition to the upscaling of particle sizes, interaction laws need to be modified/changed. These are, however, developed often in an ad-hocmanner, leading to different formulations and different solutions in terms of accuracy and efficiency. On the other hand, the multi-scaling modelling has been an effective approach to representing granular matters as continuous media, in which the equivalent constitutive models of particles are derived so that a continuous based numerical methods, such as Finite Elements, can be employed to more effectively solve large scale particle problems.
In this talk, a work that aims to establish a multi-scale approach based coarse graining framework will be presented. In this framework, some basic conditions or principles for the exact scaling between two systems will be introduced first. Then from a multi-scale perspective, and based on energy equivalency assumptions, some scaling laws similar to the exact scaling will be emerged from which a consistent coarse graining scheme may be derived.
