TY - JOUR
T1 - The effect of added Al2O3 on the propagation behavior of an Al/CuO nanoscale thermite
AU - Malchi, J. Y.
AU - Yetter, R. A.
AU - Foley, T. J.
AU - Son, S. F.
N1 - Funding Information:
Authors are supported by Los Alamos National Laboratory (LANL), which is operated for the U.S. Department of Energy under the contract DE-AC52-06NA25396. Work was supported by the Joint DoD/DOE Munitions Program under the supervision of Sherri Bingert and the U.S. Army Research Office under the Multi-University Research Initiative under Contract No. W911NF-04-1-0178. The authors give a special thank you to Adam Pacheco and Dave Oschwald for their help setting up and running the equipment that made this study possible. For his help interpreting pressure transducer results, Dr. Patrick Walter of Texas Christian University is thanked as well. This work has been assigned LA-UR #07-7888.
PY - 2008/7
Y1 - 2008/7
N2 - Three types of experiments were performed on an Al/CuO nanoscale thermite to understand the effect of adding a diluent (40nm Al2O3 particles) to the mixture: the constant volume pressure cell, the unconfined burn tray, and the instrumented burn tube. The addition of Al2O3 decreased the pressure output and reaction velocity in all three experiments. Burn tube measurements showed three reaction velocity regimes: constant velocity observed when 0% (633m/s) and 5% (570m/s) of the total weight is Al2O3, constant acceleration observed at 10% (146m/s to 544m/s over a distance of 6cm) and 15% (69m/s to 112m/s over a distance of 6cm) Al2O3, and an unstable, spiraling combustion wave at 20% Al2O3. The pressure measurements correlated to these three regimes showing a dropoff in peak pressure as Al2O3 was added to the system, with relatively no pressure increase observed when 20% of the total weight was Al2O3. Equilibrium calculations showed that the addition of Al2O3 to an Al/CuO mixture lowered the flame temperature, reducing the amount of combustion products in the gas phase, thus, hindering the presumed primary mode of forward heat transfer, convection.
AB - Three types of experiments were performed on an Al/CuO nanoscale thermite to understand the effect of adding a diluent (40nm Al2O3 particles) to the mixture: the constant volume pressure cell, the unconfined burn tray, and the instrumented burn tube. The addition of Al2O3 decreased the pressure output and reaction velocity in all three experiments. Burn tube measurements showed three reaction velocity regimes: constant velocity observed when 0% (633m/s) and 5% (570m/s) of the total weight is Al2O3, constant acceleration observed at 10% (146m/s to 544m/s over a distance of 6cm) and 15% (69m/s to 112m/s over a distance of 6cm) Al2O3, and an unstable, spiraling combustion wave at 20% Al2O3. The pressure measurements correlated to these three regimes showing a dropoff in peak pressure as Al2O3 was added to the system, with relatively no pressure increase observed when 20% of the total weight was Al2O3. Equilibrium calculations showed that the addition of Al2O3 to an Al/CuO mixture lowered the flame temperature, reducing the amount of combustion products in the gas phase, thus, hindering the presumed primary mode of forward heat transfer, convection.
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U2 - 10.1080/00102200802049471
DO - 10.1080/00102200802049471
M3 - Article
AN - SCOPUS:46249090325
SN - 0010-2202
VL - 180
SP - 1278
EP - 1294
JO - Combustion science and technology
JF - Combustion science and technology
IS - 7
ER -