An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation
Flow-enhanced nucleation of the crystal phase under shear and uniaxial extension for a monodisperse melt of n-pentacontahectane (C150H302 or C150) chains was studied by nonequilibrium molecular dynamics simulation. The resulting acceleration in the crystal nucleation rate was correlated with macrosc...
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| Format: | Article |
| Language: | English |
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Society of Rheology
2020
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| Online Access: | https://hdl.handle.net/1721.1/125808 |
| _version_ | 1826203213361053696 |
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| author | Nicholson, David Andrew Rutledge, Gregory C |
| author2 | Massachusetts Institute of Technology. Department of Chemical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Chemical Engineering Nicholson, David Andrew Rutledge, Gregory C |
| author_sort | Nicholson, David Andrew |
| collection | MIT |
| description | Flow-enhanced nucleation of the crystal phase under shear and uniaxial extension for a monodisperse melt of n-pentacontahectane (C150H302 or C150) chains was studied by nonequilibrium molecular dynamics simulation. The resulting acceleration in the crystal nucleation rate was correlated with macroscopically measurable properties of the flow field and with microscopic conformational statistics. Based on the fidelity of the observed correlations, several empirical models reported in the literature were evaluated for their abilities to account for the observed enhancement of the nucleation rate due to flow, and new models are proposed for data that do not comport with existing models. In agreement with prior reports, the nucleation rate was found to correlate well with first-normal stress difference, the second invariant of the deviatoric conformation tensor, and the stretch ratio, albeit with some differences from the existing models. New models based on conformational invariants for Kuhn segments are proposed and shown to describe the simulation data more accurately than those based on conformational behavior of entire chains. Within the applicability of the stress-optical rule, related models are proposed based on invariants of the extra stress tensor. |
| first_indexed | 2024-09-23T12:33:26Z |
| format | Article |
| id | mit-1721.1/125808 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T12:33:26Z |
| publishDate | 2020 |
| publisher | Society of Rheology |
| record_format | dspace |
| spelling | mit-1721.1/1258082024-06-25T18:32:29Z An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation Nicholson, David Andrew Rutledge, Gregory C Massachusetts Institute of Technology. Department of Chemical Engineering Flow-enhanced nucleation of the crystal phase under shear and uniaxial extension for a monodisperse melt of n-pentacontahectane (C150H302 or C150) chains was studied by nonequilibrium molecular dynamics simulation. The resulting acceleration in the crystal nucleation rate was correlated with macroscopically measurable properties of the flow field and with microscopic conformational statistics. Based on the fidelity of the observed correlations, several empirical models reported in the literature were evaluated for their abilities to account for the observed enhancement of the nucleation rate due to flow, and new models are proposed for data that do not comport with existing models. In agreement with prior reports, the nucleation rate was found to correlate well with first-normal stress difference, the second invariant of the deviatoric conformation tensor, and the stretch ratio, albeit with some differences from the existing models. New models based on conformational invariants for Kuhn segments are proposed and shown to describe the simulation data more accurately than those based on conformational behavior of entire chains. Within the applicability of the stress-optical rule, related models are proposed based on invariants of the extra stress tensor. 2020-06-15T19:37:32Z 2020-06-15T19:37:32Z 2019-05 2020-06-08T17:38:13Z Article http://purl.org/eprint/type/JournalArticle 0148-6055 1520-8516 https://hdl.handle.net/1721.1/125808 Nicholson, David A. and Gregory C. Rutledge. "An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation." Journal of Rheology 63, 3 (May 2019): 465 © 2019 The Society of Rheology en http://dx.doi.org/10.1122/1.5091945 Journal of Rheology Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Society of Rheology Prof. Rutledge via Ye Li |
| spellingShingle | Nicholson, David Andrew Rutledge, Gregory C An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation |
| title | An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation |
| title_full | An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation |
| title_fullStr | An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation |
| title_full_unstemmed | An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation |
| title_short | An assessment of models for flow-enhanced nucleation in an n-alkane melt by molecular simulation |
| title_sort | assessment of models for flow enhanced nucleation in an n alkane melt by molecular simulation |
| url | https://hdl.handle.net/1721.1/125808 |
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