TY - JOUR
T1 - Combustion behaviors resulting from bimodal aluminum size distributions in thermites
AU - Moore, Kevin
AU - Pantoya, Michelle L.
AU - Son, Steven F.
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2007
Y1 - 2007
N2 - Studies that replace a portion of the micron-size aluminum (Al) with nano-Al particles in an energetic formulation demonstrate significant performance enhancement. Little is known, however, about the critical level of nano-sized fuel particles needed to enhance the performance of the energetic composite. Ignition sensitivity and combustion velocity experiments were performed using a thermite composed of Al and molybdenum trioxide (MoO 3). Both loose powders and compressed pellets were examined. A bimodal Al particle size distribution was prepared using 4 or 20-μm-diam Al fuel particles that were replaced in 10% increments by 80-nm-diam Al particles until the fuel was 100% nano-Al. Results show that with only 20% nano-Al content, the mixtures showed reduced ignition delay times by up to 2 orders of magnitude. The combustion velocity was shown to dramatically increase as more nano-Al particles replace micron-Al particles within the mixture. This increasing trend was attributed to incomplete reactions of the micron-Al particles or significantly slower reactions such that the micron-Al particles promote cooling or quenching of the reaction.
AB - Studies that replace a portion of the micron-size aluminum (Al) with nano-Al particles in an energetic formulation demonstrate significant performance enhancement. Little is known, however, about the critical level of nano-sized fuel particles needed to enhance the performance of the energetic composite. Ignition sensitivity and combustion velocity experiments were performed using a thermite composed of Al and molybdenum trioxide (MoO 3). Both loose powders and compressed pellets were examined. A bimodal Al particle size distribution was prepared using 4 or 20-μm-diam Al fuel particles that were replaced in 10% increments by 80-nm-diam Al particles until the fuel was 100% nano-Al. Results show that with only 20% nano-Al content, the mixtures showed reduced ignition delay times by up to 2 orders of magnitude. The combustion velocity was shown to dramatically increase as more nano-Al particles replace micron-Al particles within the mixture. This increasing trend was attributed to incomplete reactions of the micron-Al particles or significantly slower reactions such that the micron-Al particles promote cooling or quenching of the reaction.
UR - http://www.scopus.com/inward/record.url?scp=33847035611&partnerID=8YFLogxK
U2 - 10.2514/1.20754
DO - 10.2514/1.20754
M3 - Article
AN - SCOPUS:33847035611
VL - 23
SP - 181
EP - 185
JO - Journal of Propulsion and Power
JF - Journal of Propulsion and Power
SN - 0748-4658
IS - 1
ER -