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Titre :
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Enhanced convective heat transfer in nongas generating nanoparticle thermites (2010)
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Auteurs :
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S. W. Dean, Auteur ;
M. L. Pantoya, Auteur ;
A. E. Gash, Auteur
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Type de document :
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Article : texte imprimé
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Dans :
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Journal of heat transfer (Vol. 132 N° 11, Novembre 2010)
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Article en page(s) :
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pp.[111201-1/7]
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Note générale :
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Physique
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Langues :
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Anglais
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Index. décimale :
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536 (Chaleur. Thermodynamique)
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Tags :
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Nanocomposites Enhanced convection reaction mechanisms Nano-alumium Thermites CuO NiO Peak pressures Flame speeds DSC TGA XRD Gas generation propagation
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Résumé :
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Flame propagation and peak pressure measurements were taken of two nanoscaled thermites using aluminum (Al) fuel and copper oxide (CuO) or nickel oxide (NiO) oxidizers in a confined flame tube apparatus. Thermal equilibrium simulations predict that the Al+CuO reaction exhibits high gas generation and, thus, high convective flame propagation rates while the Al+NiO reaction produces little to no gas and, therefore, should exhibit much lower flame propagation rates. Results show flame propagation rates ranged between 200 m/s and 600 m/s and peak pressures ranged between 1.7 MPa and 3.7 MPa for both composites. These results were significantly higher than expected for the Al+NiO, which generates virtually no gas. For nanometric Al particles, oxidation has recently been described by a melt-dispersion oxidation mechanism that involves a dispersion of high velocity alumina shell fragments and molten Al droplets that promote a pressure build-up by inducing a bulk movement of fluid. This mechanism unique to nanoparticle reaction may promote convection without the need for additional gas generation.
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DEWEY :
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536
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ISSN :
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0022-1481
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En ligne :
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http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode=strresults&sort=chron&maxdisp=25&threshold=0&pjournals=JBENDY&pjournals=JHTRAO&pyears=2010&possible1zone=article&fromvolume=132&fromissue=11&OUTLOG=NO&sti=yes&viewabs=JHTRAO&k
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