TY - JOUR
T1 - Multiscale mechanical analysis of silicon nanostructures by combined finite temperature models
AU - Tang, Zhi
AU - Aluru, N. R.
N1 - Funding Information:
This work is supported by the National Science Foundation under Grant Nos. 0103447, 0228390, 0403020 and 0519920.
PY - 2008/7/1
Y1 - 2008/7/1
N2 - A multiscale model based on finite element method is proposed for mechanical analysis of silicon nanostructures at finite temperature. By using a criterion based on the Helmholtz free energy, appropriate lattice dynamics models are seamlessly combined to compute mechanical properties. At each computational point, if the Helmholtz free energy calculated from the local quasiharmonic model (LQHM) is close enough to that computed from the quasiharmonic model in the reciprocal space (QHMK), the LQHM model is used to calculate the mechanical properties, otherwise, the QHMK model is used. By using a silicon nanostructure as an example, it is shown that the combined QHMK/LQHM multiscale model significantly reduces the computational cost but maintains the accuracy of the full QHMK model. Molecular dynamics results are also used for validation of the combined multiscale model.
AB - A multiscale model based on finite element method is proposed for mechanical analysis of silicon nanostructures at finite temperature. By using a criterion based on the Helmholtz free energy, appropriate lattice dynamics models are seamlessly combined to compute mechanical properties. At each computational point, if the Helmholtz free energy calculated from the local quasiharmonic model (LQHM) is close enough to that computed from the quasiharmonic model in the reciprocal space (QHMK), the LQHM model is used to calculate the mechanical properties, otherwise, the QHMK model is used. By using a silicon nanostructure as an example, it is shown that the combined QHMK/LQHM multiscale model significantly reduces the computational cost but maintains the accuracy of the full QHMK model. Molecular dynamics results are also used for validation of the combined multiscale model.
KW - Finite temperature
KW - k-Space quasiharmonic
KW - Local quasiharmonic
KW - Multiscale analysis
KW - Quasicontinuum method
KW - Silicon nanostructures
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U2 - 10.1016/j.cma.2007.11.018
DO - 10.1016/j.cma.2007.11.018
M3 - Article
AN - SCOPUS:48049104570
SN - 0045-7825
VL - 197
SP - 3215
EP - 3224
JO - Computer Methods in Applied Mechanics and Engineering
JF - Computer Methods in Applied Mechanics and Engineering
IS - 41-42
ER -