2014/11/09 by Jerry Zhijian Yang, Yang, Jerry Zhijian, Shukai Du +1
Earth and Planetary Sciences · Engineering · Materials Science · Physics and Astronomy · #Computational Physics (physics.comp-ph) #Elasticity and Material Modeling #FOS: Physical sciences #High-pressure geophysics and materials #Microstructure and mechanical properties #physics.comp-ph
paper · pdf · doi:10.48550/arxiv.1411.2227
arxiv created 2014/11/09 · openalex publication_date 2014/11/09 · arxiv updated 2014/11/11 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Irving and Kirkwood formulism (IK formulism) provides a way to compute continuum mechanics quantities at certain location in terms of molecular variables. To make the approach more practical in computer simulation, Hardy proposed to use a spacial kernel function that couples continuum quantities with atomistic information. To reduce irrational fluctuations, Murdoch proposed to use a temporal kernel function to smooth the physical quantities obtained in Hardy's approach. In this paper, we generalize the original IK formulism to systematically incorporate both spacial and temporal average. The Cauchy stress tensor is derived in this generalized IK formulism (g-IK formulism). Analysis is given to illuminate the connection and difference between g-IK formulism and traditional temporal post-process approach. The relationship between Cauchy stress and first Piola-Kirchhoff stress is restudied in the framework of g-IK formulism. Numerical experiments using molecular dynamics are conducted to examine the analysis results.