Effective thermal conductivity of rectangular nanowires based on phonon hydrodynamics
A mathematical model is presented for thermal transport in nanowires with rectangular cross sections. Expressions for the effective thermal conductivity of the nanowire across a range of temperatures and cross-sectional aspect ratios are obtained by solving the Guyer–Krumhansl hydrodynamic equation...
| Main Authors: | , , , , |
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| Format: | Journal article |
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Elsevier
2018
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| _version_ | 1797089682698272768 |
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| author | Calvo-Schwarzwälder, M Hennessy, M Torres, P Myers, T Alvarez, F |
| author_facet | Calvo-Schwarzwälder, M Hennessy, M Torres, P Myers, T Alvarez, F |
| author_sort | Calvo-Schwarzwälder, M |
| collection | OXFORD |
| description | A mathematical model is presented for thermal transport in nanowires with rectangular cross sections. Expressions for the effective thermal conductivity of the nanowire across a range of temperatures and cross-sectional aspect ratios are obtained by solving the Guyer–Krumhansl hydrodynamic equation for the thermal flux with a slip boundary condition. Our results show that square nanowires transport thermal energy more efficiently than rectangular nanowires due to optimal separation between the boundaries. However, circular nanowires are found to be even more efficient than square nanowires due to the lack of corners in the cross section, which locally reduce the thermal flux and inhibit the conduction of heat. By using a temperature-dependent slip coefficient, we show that the model is able to accurately capture experimental data of the effective thermal conductivity obtained from Si nanowires, demonstrating that phonon hydrodynamics is a powerful framework that can be applied to nanosystems even at room temperature. |
| first_indexed | 2024-03-07T03:07:34Z |
| format | Journal article |
| id | oxford-uuid:b312bdf6-c864-40ac-b0cf-0697ed88c27a |
| institution | University of Oxford |
| last_indexed | 2024-03-07T03:07:34Z |
| publishDate | 2018 |
| publisher | Elsevier |
| record_format | dspace |
| spelling | oxford-uuid:b312bdf6-c864-40ac-b0cf-0697ed88c27a2022-03-27T04:16:24ZEffective thermal conductivity of rectangular nanowires based on phonon hydrodynamicsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:b312bdf6-c864-40ac-b0cf-0697ed88c27aSymplectic Elements at OxfordElsevier2018Calvo-Schwarzwälder, MHennessy, MTorres, PMyers, TAlvarez, FA mathematical model is presented for thermal transport in nanowires with rectangular cross sections. Expressions for the effective thermal conductivity of the nanowire across a range of temperatures and cross-sectional aspect ratios are obtained by solving the Guyer–Krumhansl hydrodynamic equation for the thermal flux with a slip boundary condition. Our results show that square nanowires transport thermal energy more efficiently than rectangular nanowires due to optimal separation between the boundaries. However, circular nanowires are found to be even more efficient than square nanowires due to the lack of corners in the cross section, which locally reduce the thermal flux and inhibit the conduction of heat. By using a temperature-dependent slip coefficient, we show that the model is able to accurately capture experimental data of the effective thermal conductivity obtained from Si nanowires, demonstrating that phonon hydrodynamics is a powerful framework that can be applied to nanosystems even at room temperature. |
| spellingShingle | Calvo-Schwarzwälder, M Hennessy, M Torres, P Myers, T Alvarez, F Effective thermal conductivity of rectangular nanowires based on phonon hydrodynamics |
| title | Effective thermal conductivity of rectangular nanowires based on phonon hydrodynamics |
| title_full | Effective thermal conductivity of rectangular nanowires based on phonon hydrodynamics |
| title_fullStr | Effective thermal conductivity of rectangular nanowires based on phonon hydrodynamics |
| title_full_unstemmed | Effective thermal conductivity of rectangular nanowires based on phonon hydrodynamics |
| title_short | Effective thermal conductivity of rectangular nanowires based on phonon hydrodynamics |
| title_sort | effective thermal conductivity of rectangular nanowires based on phonon hydrodynamics |
| work_keys_str_mv | AT calvoschwarzwalderm effectivethermalconductivityofrectangularnanowiresbasedonphononhydrodynamics AT hennessym effectivethermalconductivityofrectangularnanowiresbasedonphononhydrodynamics AT torresp effectivethermalconductivityofrectangularnanowiresbasedonphononhydrodynamics AT myerst effectivethermalconductivityofrectangularnanowiresbasedonphononhydrodynamics AT alvarezf effectivethermalconductivityofrectangularnanowiresbasedonphononhydrodynamics |