The speed of propagation of a premixed turbulent flame correlates with the
intensity of the turbulence encountered by the flame. One consequence of
this property is that premixed flames in both laboratory experiments and
practical combustors require some type of stabilization mechanism to prevent
blow-off and flashback. The stabilization devices often introduce a level of
geometric complexity that is prohibitive for detailed computational studies of
turbulent flame dynamics. Furthermore, the stabilization introduces additional
fluid mechanical complexity into the overall combustion process that can
complicate the analysis of fundamental flame properties. To circumvent these
difficulties we introduce a simple, heuristic feedback control algorithm that
allows us to computationally stabilize a turbulent premixed flame in a simple
geometric configuration. For the simulations, we specify turbulent inflow
conditions and dynamically adjust the integrated fueling rate to control the mean
location of the flame in the domain. We outline the numerical procedure,
and illustrate the behavior of the control algorithm on methane flames at
various equivalence ratios in two dimensions. The simulation data are used to
study the local variation in the speed of propagation due to flame surface
curvature.
Keywords
active control, statistically stationary, turbulent flames