A mixture fraction space model for counterflow diffusion flames with incident electric field

Abstract

Applying an external electric field is a well-known strategy to control combustion processes. However, the high computational complexity of the numerical approaches formulated so far often forestalls the study of configurations of practical and scientific interest. This work proposes a reduced order model for predicting the behaviour of diffusion flames impinged by an external electric field that is based on the classic mixture fraction space formulation. The model takes into account differential diffusion effects as wells as the electric drift of ions in order to predict the species distribution in the mixing layer. The results obtained with the proposed model are in good agreement with those of the two-dimensional calculations presented by Di Renzo et al. (2018) for the case of a methane/air laminar counterflow diffusion flames impinged by sub-breakdown DC electric fields. The reduction of the computational cost associated with the prediction of each flame by a factor one million has allowed the authors to perform a preliminary exploration of the diffusion flame phase-space, in particular defining the variation of the ion-current produced by the reacting layer along its S-curve.