A new efficient variant of hot-QC, the finite temperature version of the quasicontinuum (QC) method, is presented. In the original formulation of hot-QC, a dynamically evolving atomistic region is coupled with either a dynamic (hot-QC-dynamic) or a static (hot-QC-static) continuum region. In the current work, a free energy minimization method is employed in which atom positions in both the atomistic and continuum regions always occupy equilibrium positions. The effect of ghost forces at the interface of the atomistic and continuum regions is discussed for all three variants of hot-QC using two examples: a perfect cubic crystal and a Lomer dislocation dipole. Errors due to ghost forces and due to mesh entropy are considered and the efficacy of their correction terms are evaluated. It is shown that the proposed free energy minimization method has comparable accuracy to the other methods with significantly higher efficiency.
|Original language||English (US)|
|Number of pages||19|
|Journal||International Journal for Numerical Methods in Engineering|
|State||Published - Oct 30 2022|
Bibliographical noteFunding Information:
Woo Kyun Kim, Aditya Kavalur, and Ellad B. Tadmor were supported in part by the National Science Foundation (NSF) through a collaborative research grant under Award Numbers CMMI‐1463038 and CMMI‐1462807, respectively. Ellad B. Tadmor was also supported in part by NSF Award DMR‐1607670.
© 2022 The Authors. International Journal for Numerical Methods in Engineering published by John Wiley & Sons Ltd.
- atomistic and continuum coupling
- free energy