Silicon alloying enhances fast heating rate combustion of aluminum particles
- Texas Tech University, Lubbock, TX (United States)
Alloys and composites of aluminum (Al) have shown promise in regulating and enhancing particle combustion for energy generation applications. Recent work on aluminum-silicon (Al-Si) spherical alloy particles has shown improved combustion at low heating rates through enhanced diffusion accompanying a lower melting temperature. This study extends reactivity analysis to higher heating rates, comparing oxidation of Al-Si with Al. Flame speeds of Al-Si powder mixed with molybdenum trioxide (MoO3) powder (Al-Si+MoO3) exhibited a faster transition to steady propagation relative to Al+MoO3. Bomb calorimetry experiments revealed up to 5.8% greater early temperature rise for Al-Si powder. Rapid steady propagation for Al-Si mixture and faster temperature rise for Al-Si particles were attributed to accelerated kinetics evidenced in thermal equilibrium analysis of the mixtures using a differential scanning calorimeter (DSC). Larger DSC exotherms in the early stages of oxidation (i.e., 480–720 °C) correlated with early heat release and promoted steady flame propagation for Al-Si+MoO3 compared with Al+MoO3. Furthermore, in multiple heating rate DSC studies, Al-Si+MoO3 ignited at a lower heating rate (i.e., 15 ⁰C/min) than Al+MoO3 (i.e., 20 ⁰C/min). Both mixtures ignited at temperatures less than 625 °C which is above the melting temperature of Al-Si (574 °C) and below Al (659 °C). Thus, alloy particle fuels with enhanced diffusion-controlled kinetics promote steady flame propagation and show promise for energy generation applications. This is especially promising for technologies driven by enhanced condensed phase combustion such as some propellant additives or applications dependent on reliable burn rates such as pyrotechnic time delay formulations and primers.
- Research Organization:
- Texas Tech Univ., Lubbock, TX (United States)
- Sponsoring Organization:
- USDOE National Nuclear Security Administration (NNSA); US Department of the Navy, Office of Naval Research (ONR)
- Grant/Contract Number:
- NA0003988; N00014-19-1-2082; N00014-22-1-2006; N00014-21-1-2519
- OSTI ID:
- 1976996
- Alternate ID(s):
- OSTI ID: 1869020
- Journal Information:
- Combustion and Flame, Vol. 241, Issue C; ISSN 0010-2180
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Processing of transition metal silicides for high-temperature applications
3D simulations of spinlike flames in Co/Al multilayers with enhanced conduction losses