Modelling transient heat conduction in solids at multiple length and time scales: A coupled non-equilibrium molecular dynamics/continuum approach

Journal Article · Tue Oct 20 04:00:00 EDT 2009 · Journal of Computational Physics

DOI:https://doi.org/10.1016/j.jcp.2009.06.035· OSTI ID:21308116

Jolley, Kenny ^[1]

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1. Department of Engineering, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)

A method for controlling the thermal boundary conditions of non-equilibrium molecular dynamics simulations is presented. The method is simple to implement into a conventional molecular dynamics code and independent of the atomistic model employed. It works by regulating the temperature in a thermostatted boundary region by feedback control to achieve the desired temperature at the edge of an inner region where the true atomistic dynamics are retained. This is necessary to avoid intrinsic boundary effects in non-equilibrium molecular dynamics simulations. Three thermostats are investigated: the global deterministic Nose-Hoover thermostat and two local stochastic thermostats, Langevin and stadium damping. The latter thermostat is introduced to avoid the adverse reflection of phonons that occurs at an abrupt interface. The method is then extended to allow atomistic/continuum models to be thermally coupled concurrently for the analysis of large steady state and transient heat conduction problems. The effectiveness of the algorithm is demonstrated for the example of heat flow down a three-dimensional atomistic rod of uniform cross-section subjected to a variety of boundary conditions.

• OSTI ID: 21308116
• Journal Information: Journal of Computational Physics, Journal Name: Journal of Computational Physics Journal Issue: 19 Vol. 228; ISSN JCTPAH; ISSN 0021-9991
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALGORITHMS
BOUNDARY CONDITIONS
CROSS SECTIONS
EQUILIBRIUM
HEAT FLUX
MOLECULAR DYNAMICS METHOD
NOSE
PHONONS
SIMULATION
STEADY-STATE CONDITIONS
STOCHASTIC PROCESSES
THERMAL CONDUCTION
THERMOSTATS
THREE-DIMENSIONAL CALCULATIONS