TY - JOUR
T1 - Detailed numerical simulation and experiments of a steadily burning micron-sized aluminum droplet in hot steam-dominated flows
AU - Qiu, Yue
AU - Feng, Sheng
AU - Wu, Zhiyong
AU - Xu, Shijie
AU - Ruan, Can
AU - Bai, Xue Song
AU - Nilsson, Elna J.K.
AU - Aldén, Marcus
AU - Li, Zhongshan
N1 - Publisher Copyright:
© 2024 The Author(s)
PY - 2024/1
Y1 - 2024/1
N2 - Detailed numerical simulations are conducted in comparison with experimental results to study the flame structure and burning rate of a steadily burning aluminum droplet in hot steam-dominated environments. The droplet surface temperature, flame temperature, and flame stabilization position are measured along with the droplet burning rate estimated from the droplet size evolution. A numerical model accounting for detailed transport properties and chemical kinetics is presented and applied to unveil the flame structure, species and temperature distributions, and heat/mass transfer between the droplet and the surrounding gas. The numerical results of the temperature, velocity, and species distribution profiles demonstrate that the aluminum vapor flame is of classical diffusion flame structure, where near the droplet, there is a non-negligible amount of AlOAl apart from the main product Al2O3(l). This supports the deposition and formation of an alumina cap on the surface proposed in the literature. The simulation correctly captured the flame temperature and flame stabilization distance for a range of droplet sizes. Net heat flux analysis shows that conduction heat from the flame front accounts for less than 30% of the heat needed in aluminum evaporation, which warrants further quantification on other heat sources. The experimental and numerical results enrich the knowledge of the heat/mass transfer and chemical reactions near the droplet, which helps deepen the understanding of aluminum droplet burning.
AB - Detailed numerical simulations are conducted in comparison with experimental results to study the flame structure and burning rate of a steadily burning aluminum droplet in hot steam-dominated environments. The droplet surface temperature, flame temperature, and flame stabilization position are measured along with the droplet burning rate estimated from the droplet size evolution. A numerical model accounting for detailed transport properties and chemical kinetics is presented and applied to unveil the flame structure, species and temperature distributions, and heat/mass transfer between the droplet and the surrounding gas. The numerical results of the temperature, velocity, and species distribution profiles demonstrate that the aluminum vapor flame is of classical diffusion flame structure, where near the droplet, there is a non-negligible amount of AlOAl apart from the main product Al2O3(l). This supports the deposition and formation of an alumina cap on the surface proposed in the literature. The simulation correctly captured the flame temperature and flame stabilization distance for a range of droplet sizes. Net heat flux analysis shows that conduction heat from the flame front accounts for less than 30% of the heat needed in aluminum evaporation, which warrants further quantification on other heat sources. The experimental and numerical results enrich the knowledge of the heat/mass transfer and chemical reactions near the droplet, which helps deepen the understanding of aluminum droplet burning.
KW - Direct numerical simulation
KW - Eulerian-based framework
KW - Flame structure
KW - Metal combustion
KW - Micron-sized aluminum droplet
U2 - 10.1016/j.proci.2024.105717
DO - 10.1016/j.proci.2024.105717
M3 - Article
AN - SCOPUS:85201709720
SN - 1540-7489
VL - 40
JO - Proceedings of the Combustion Institute
JF - Proceedings of the Combustion Institute
IS - 1-4
M1 - 105717
ER -