Kakutkina N.A., Korzhavin A.A., Rychkov A.D. Ignition of the
waves of filtration gas combustion with open flame Institute of
chemical kinetics and combustion SB RAS, Novosibirsk, Russia
Institute of computational technologies SB RAS, Novosibirsk, Russia
Slide 2 FILTRATION GAS COMBUSTION (FGC) Steady-state FGC waves are
well known: Steady-state FGC regimes Mechanisms of wave propagation
at different regimes Parametric dependencies of u and T Nature of
combustion limits Mathematical models of FGC Slide 3
Nonsteady-state regimes of FGC FGC wave ignition FGC wave quenching
FGC wave propagation in nonsteady-state parametric condition The
object of the work is numerical study of FGC wave ignition with
open flame Slide 4 Experimental set up 1 2 3 4 5 6 8 9 10 11 7
Slide 5 Modeling system u0u0 Fresh gas Combustion products u0u0
Fresh gas Combustion products u0u0 Combustion products a c b Slide
6 Mathematical model Slide 7 Modeling results Slide 8 Trajectory of
combustion wave propagation Evolution of temperature profiles of
porous medium under filtration combustion Modeling results Slide 9
Ignition of FGC wave Temperature profiles of gas (thin lines) and
porous medium (thick lines) in the stage of combustion wave
formation in porous body. Time from ignition moment: 0.1 s (1), 5 s
(2), then in minutes 0.5 (3), 1.5 (4), 4.5 (5),5 (6), 5.5 (7), 6
(8). Velocity of gas flow 0.24 m/s. Dashed line shows right
boundary of porous body. Slide 10 Effect of thermal conductivity of
porous body on time of FGC wave ignition Slide 11 Dependencies of
time of FGC wave ignition on gas velocity h=75 mm, s=70 W/(m ), d,
mm: 3.3 (1), 2.7 (2), 2 (3). Slide 12 Dependencies of time of FGC
wave ignition in porous body on body length s, W/(m ): 1 (1), 20
(2), 100 (3). Slide 13 Dependencies of critical length (1) and
maximum heating up of porous body (2) on channel diameter s=70 W/(m
), v 0 =22 cm/s Slide 14 Trajectories of flame entering and
propagation in porous body with different layers at right boundary
of porous body 1 without layer, 2 metal grid with g =0.8, 3 the
same, but with g =0.7, 4 perforated metal plate with g =0.2. Gas
velocity 0.3 m/s. Dashed lines show layer position. Slide 15
Conclusions 1.Mathematical modeling of FGC wave ignition in porous
body with open flame was carried out. Mechanisms acting at FGC wave
formation was revealed. 2.Dependencies of ignition time were
established on thermal conductivity of porous body, filtration gas
velocity, porous body length. Existence of critical conditions for
FGC wave ignition was shown. 3.Methods of influence on the time of
FGC wave ignition are considered.
