ID#: 17
Abstract Title: Classification of Ignition Processes of Premixed Gases
Session Title: Ignition Phenomena
Session Date: 7/31/01
Session Start Time: 8:30 AM
Contributing Author: Brutscher, T.
Organization: Engler-Bunte-Institut, Combustion Technology Section
Country: Germany
Authors: Tobias Brutscher, Wolfgang Leuckel, Henning Bockhorn
Short Abstract: One-dimensional ignition processes of quiescent methane-air-mixtures were investigated in detail with the simulation code INSFLA. On the basis phenomenological considerations it was possible to divide induced ignition processes in three regimes. At large radii of the external energy source the ignition process is dominated by the formation of a pool of radicals (induction time). In this regime a self-sustained flame front has been established when ignition takes place. At small radii and short times of the external energy source it is necessary to reach a critical flame ball size. At the transition between both regimes diffusion of heat and mass during the heat release of the external energy source plays an important role for the ignition process. It was possible to derive simple equations to calculate minimum ignition energies for the different regimes.