A multi-grid sampling multi-scale method for crack initiation and propagation

TL;DR

This paper introduces a multi-grid sampling multi-scale (MGSMS) method that couples FEM, XFEM, and MD to simulate crack initiation and propagation from microscopic to macroscopic scales, improving accuracy and efficiency.

Contribution

The paper presents a novel multi-grid sampling multi-scale approach integrating FEM, XFEM, and MD for comprehensive crack analysis across scales.

Findings

Successfully simulates crack initiation and propagation.

Efficiently extracts crack coordinates using image recognition.

Reduces computational cost with Latin hypercube sampling.

Abstract

In this study, a multi-grid sampling multi-scale (MGSMS) method is proposed by coupling with finite element (FEM), extended finite element (XFEM) and molecular dynamics (MD) methods.Crack is studied comprehensively from microscopic initiations to macroscopic propagation by MGSMS method. In order to establish the coupling relationship between macroscopic and microscopic model, multi-grid FEM is used to transmit the macroscopic displacement boundary conditions to the atomic model and the multi-grid XFEM is used to feedback the microscopic crack initiations to the macroscopic model. Moreover, an image recognition based crack extracting method is proposed to extract the crack coordinate from the MD result files of efficiently and the Latin hypercube sampling method is used to reduce the computational cost of MD. Numerical results show that MGSMS method can be used to calculate micro-crack initiations and transmit it to the macro-crack model. The crack initiation and propagation simulation of plate under mode I loading is completed.