Characterizing I-V Curves for Non-Premixed Methane Flames Stabilized on Different Burner Configurations

Ion winds dominate the effects observed when an external electric field is applied to a hydrocarbon flame. Such effects require, however, a sufficient ion source to generate the ion wind. Electric field combustion studies rarely report the rate of ions passing through the system. Current voltage curves, I-V curves, represent how effectively electrical energy is converted into kinetic energy in the flow. This study experimentally obtains I-V curves for different non-premixed burner configurations. The results show that the burner configuration has a significant effect, particularly with field strengths above the saturation point. Increased ion current above saturation and ion current/flame instabilities were observed. Experiments also show that secondary ionization can account for a portion of the increase in ion current, but flame contours point to a stronger correlation with flame geometry and the ability of an ion wind to enhance localized mixing by promoting air entrainment.