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Non-Fourier heat conduction in carbon nanotubes / Hai-Dong Wang in Journal of heat transfer, Vol. 134 N° 5 (Mai 2012) 

Public ISBD [article]  in Journal of heat transfer > Vol. 134 N° 5 (Mai 2012) . - 06 p. Titre : Non-Fourier heat conduction in carbon nanotubes Type de document : texte imprimé Auteurs : Hai-Dong Wang, Auteur ; Bing-Yang Cao, Auteur ; Zeng-Yuan Guo, Auteur Année de publication : 2012 Article en page(s) : 06 p. Note générale : heat transfer Langues : Anglais (eng) Mots-clés : non-Fourier  heat  conduction;  thermomass;  carbon  nanotubes;  thermal  conductivity Index. décimale : 536 Chaleur. Thermodynamique Résumé : Fourier's law is a phenomenological law to describe the heat transfer process. Although it has been widely used in a variety of engineering application areas, it is still questionable to reveal the physical essence of heat transfer. In order to describe the heat transfer phenomena universally, Guo has developed a general heat conduction law based on the concept of thermomass, which is defined as the equivalent mass of phonon gas in dielectrics according to Einstein's mass–energy relation. The general law degenerates into Fourier's law when the thermal inertia is neglected as the heat flux is not very high. The heat flux in carbon nanotubes (CNTs) may be as high as 1012 W/m2. In this case, Fourier's law no longer holds. However, what is estimated through the ratio of the heat flux to the temperature gradient by molecular dynamics (MD) simulations or experiments is only the apparent thermal conductivity (ATC); which is smaller than the intrinsic thermal conductivity (ITC). The existing experimental data of single-walled CNTs under the high-bias current flows are applied to study the non-Fourier heat conduction under the ultrahigh heat flux conditions. The results show that ITC and ATC are almost equal under the low heat flux conditions when the thermal inertia is negligible, while the difference between ITC and ATC becomes more notable as the heat flux increases or the temperature drops. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000005 [...] [article] Non-Fourier heat conduction in carbon nanotubes [texte imprimé] / Hai-Dong Wang, Auteur ; Bing-Yang Cao, Auteur ; Zeng-Yuan Guo, Auteur . - 2012 . - 06 p. heat transfer Langues : Anglais (eng) in Journal of heat transfer > Vol. 134 N° 5 (Mai 2012) . - 06 p. Mots-clés : non-Fourier  heat  conduction;  thermomass;  carbon  nanotubes;  thermal  conductivity Index. décimale : 536 Chaleur. Thermodynamique Résumé : Fourier's law is a phenomenological law to describe the heat transfer process. Although it has been widely used in a variety of engineering application areas, it is still questionable to reveal the physical essence of heat transfer. In order to describe the heat transfer phenomena universally, Guo has developed a general heat conduction law based on the concept of thermomass, which is defined as the equivalent mass of phonon gas in dielectrics according to Einstein's mass–energy relation. The general law degenerates into Fourier's law when the thermal inertia is neglected as the heat flux is not very high. The heat flux in carbon nanotubes (CNTs) may be as high as 1012 W/m2. In this case, Fourier's law no longer holds. However, what is estimated through the ratio of the heat flux to the temperature gradient by molecular dynamics (MD) simulations or experiments is only the apparent thermal conductivity (ATC); which is smaller than the intrinsic thermal conductivity (ITC). The existing experimental data of single-walled CNTs under the high-bias current flows are applied to study the non-Fourier heat conduction under the ultrahigh heat flux conditions. The results show that ITC and ATC are almost equal under the low heat flux conditions when the thermal inertia is negligible, while the difference between ITC and ATC becomes more notable as the heat flux increases or the temperature drops. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000005 [...]