The present study has been performed to explore the local reaction zone configuration of high intensity turbulent premixed flames in detail by using a micro-electrostatic probe of two identical sensors. The local reaction zone configuration is shown to be determined by analyzing the ion current fluctuations. The radii of the local reaction zone curvatures are examined and expressed in frequency distribution. The radii of curvatures of the local reaction zone convex toward unburned mixture are distributed in a wider range than those convex toward burned gas. The mean radius of the local reaction zone curvatures decreases as the turbulent intensity increases, while the smallest and the most probable radii of curvatures scarcely change with the turbulent intensity. Both the most probable and the mean radii of curvatures measured in the present study are larger than the micro scale of turbulence. It is presumed that even in intense turbulence, whose Kolmogoroff scale is smaller than a laminar flame thickness, small scale turbulent eddies may scarcely affect the local reaction zone configuration. Any appreciable effects of turbulent intensity can not be confirmed on the inner structure of the local reaction zone. The inner structure of a laminar premixed flame would be preserved at the local reaction zone of turbulent premixed flames examined in the present study, which are of characteristics in the broken flame regime.
ASJC Scopus subject areas
- Chemical Engineering(all)
- Fuel Technology
- Energy Engineering and Power Technology
- Physics and Astronomy(all)