The quenching of premixed laminar flames at various constant
pressures was studied through numerical simulation, with the
Trajectory Generated Lower Dimensional Manifold (TGLDM) method used
to employ detailed chemical mechanisms for stoichiometric methane
and heptane flames. The method was validated at lower pressures and
wall temperatures. The laminar flame speed predicted by the TGLDM
method agrees reasonably well with experimental data reported in
the literature. The peak heat flux at quenching was found to be
under-predicted by 30-40% of the most current experimental
data.
The quench distance was calculated for pressures of 1, 2, 20 and
40 bar, with wall temperatures of 300 and 600 K and fresh gas
temperature of 300 K. The quench distance was found to decrease
with increasing pressure in a manner similar to previous studies.
The value of quench distance for heptane was found to be smaller
than that of methane by a factor of ~30% over all pressures.
The peak heat flux values were used to evaluate the thermal
model of Boust et al., for calculating quench distance and was
found to predict the right trend, though the quench distance values
are lower than those observed in experiment. The applicability of
these results to internal combustion engines is briefly discussed
by calculating a rough estimate of the fuel left unburned in the
quenching layer for a spark-ignited engine, and a proposal for the
computational implementation of Boust's thermal model is
explained.