Elevated pressure increases the effect of electric fields on ionic wind in methane premixed jet flames

Abstract

Electric fields are useful for enhancing stability limits of flames, increasing the overall burning rate and reducing soot emissions. The electric body force has been known as a key element behind the aforemen- tioned augmentation, and recent studies have provided clear picture for the resulted flow modification. In this study, we investigate the effects of pressure on an ionic wind by applying transverse electric fields to methane premixed jet flames in a pressurized chamber up to 2 atm. We investigated the voltage-current re- sponse by varying the pressure, the equivalence ratio of the mixture, and the flow rate. We found that the saturated current for lean and stoichiometric mixtures was not affected by the pressure, while the saturated current of rich premixed flames changed significantly. We developed a model to predict the voltage-current behavior and the ion-production rate, which we validated using experimental results. Based on our flow field measurements, we found that elevated pressure conditions enhanced ionic wind-driven mass transport. These results support the use of electric fields in a high-pressure environment.