About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
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| Symposium
|
Microstructure-Sensitive Modeling Across Length Scales: An MPMD/SMD Symposium in Honor of David L. McDowell
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| Presentation Title |
Unifying Atomistic and Continuum Definitions of Temperature for Multiscale Simulation of Finite-Temperature Processes |
| Author(s) |
Youping Chen |
| On-Site Speaker (Planned) |
Youping Chen |
| Abstract Scope |
The definition of temperature has been a subject of a foundational debate. It is a basic quantity in thermodynamics, statistical mechanics, and continuum mechanics but a derived quantity in molecular kinetic theory, experimental measurements and atomistic simulations. This difference has been a major obstacle in the development of multiscale methods. This talk aims to address this obstacle. We will first rederive the conservation equation of linear momentum from the atomistic, using the theory of distributions, by defining temperature as a derived quantity as that in kinetic theory. The formulation leads to a momentum equation that, supplemented by an interatomic potential, completely governs thermomechanical processes from atomistic to the continuum. Numerical examples will be presented to test the formulation in capturing the effect of temperature and thermal fluctuations, including thermally activated dislocation motion, dislocation formation during epitaxial processes, and attenuation of waves as a result of their interaction with thermal phonons. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Modeling and Simulation, Nanotechnology |