TY - JOUR
T1 - Computational Study of Nonadiabatic Wave Patterns in Smouldering Combustion under Microgravity
JO - East Asian Journal on Applied Mathematics
VL - 2
SP - 138
EP - 149
PY - 2018
DA - 2018/02
SN - 5
DO - http://doi.org/10.4208/eajam.010914.250315a
UR - https://global-sci.org/intro/article_detail/eajam/10917.html
KW - Filtration combustion, smouldering, fingering instability, nonadiabatic, chemical kinetics.
AB - <p style="text-align: justify;">We numerically study a thermal-diffusive model for smouldering combustion
under microgravity with convective heat losses. In accordance with previous experimental
observations, it is well known that porous materials burning against a gaseous oxidiser
under microgravity exhibit various finger-like char patterns due to the destabilising
effect of oxidiser transport. There is a close resemblance between the pattern-forming
dynamics observed in the experiments with the mechanism of thermal-diffusive instability,
similar to that occurring in low Lewis number premixtures. At large values of the
Lewis number, the finger-like pattern coalesces and propagates as a stable front reminiscent
of the pattern behaviour at large Péclet numbers in diffusion-limited systems. The
significance of the order of the chemical kinetics for the coexistence of both upstream
and downstream smoulder waves is also considered.</p>