Flow and plasticity via nonequilibrium molecular dynamics
Abstract
The viscous flow of fluids and the plastic flow of solids, such as metals, are interesting from both the practical and the theoretical points of view. Atomistic molecular dynamics simulations provide a way of visualizing and understanding these flows in a detailed microscopic way. Simulations are necessarily carried out at relatively high rates of strain. For this reason they are ideally suited to the study of nonlinear flow phenomena: normal stresses induced by shear deformation, stress rotation, and the coupling of stress with heat flow, for instance. The simulations require appropriate boundary conditions, forces, and equations of motion. Newtonian mechanics is relatively inefficient for this simulation task. A modification, Nonequilibrium Molecular Dynamics, has been developed to simulate nonequilibrium flows. By now, many highstrainrate rheological studies of flowing (viscous) fluids and (plastic) solids have been carried out. Here I describe the new methods used in the simulations and some results obtained in this way. A threebody shearflow exercise is appended to make these ideas more concrete.
 Authors:
 Publication Date:
 Research Org.:
 Lawrence Livermore National Lab., CA (USA)
 OSTI Identifier:
 6217365
 Report Number(s):
 UCRL90904; CONF84052473
ON: DE85001011
 DOE Contract Number:
 W7405ENG48
 Resource Type:
 Conference
 Resource Relation:
 Conference: ISPRA EURATOM school on computer simulation in physical metallurgy, Ispra, Italy, 21 May 1984
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; FLOW MODELS; MOLECULAR MODELS; VISCOUS FLOW; NONLINEAR PROBLEMS; PLASTICITY; SIMULATION; FLUID FLOW; MATHEMATICAL MODELS; MECHANICAL PROPERTIES; 640410*  Fluid Physics General Fluid Dynamics
Citation Formats
Hoover, W.G. Flow and plasticity via nonequilibrium molecular dynamics. United States: N. p., 1984.
Web.
Hoover, W.G. Flow and plasticity via nonequilibrium molecular dynamics. United States.
Hoover, W.G. Mon .
"Flow and plasticity via nonequilibrium molecular dynamics". United States.
doi:. https://www.osti.gov/servlets/purl/6217365.
@article{osti_6217365,
title = {Flow and plasticity via nonequilibrium molecular dynamics},
author = {Hoover, W.G.},
abstractNote = {The viscous flow of fluids and the plastic flow of solids, such as metals, are interesting from both the practical and the theoretical points of view. Atomistic molecular dynamics simulations provide a way of visualizing and understanding these flows in a detailed microscopic way. Simulations are necessarily carried out at relatively high rates of strain. For this reason they are ideally suited to the study of nonlinear flow phenomena: normal stresses induced by shear deformation, stress rotation, and the coupling of stress with heat flow, for instance. The simulations require appropriate boundary conditions, forces, and equations of motion. Newtonian mechanics is relatively inefficient for this simulation task. A modification, Nonequilibrium Molecular Dynamics, has been developed to simulate nonequilibrium flows. By now, many highstrainrate rheological studies of flowing (viscous) fluids and (plastic) solids have been carried out. Here I describe the new methods used in the simulations and some results obtained in this way. A threebody shearflow exercise is appended to make these ideas more concrete.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jun 11 00:00:00 EDT 1984},
month = {Mon Jun 11 00:00:00 EDT 1984}
}

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