Characterization of Blow Out Links for a V-Gutter Stabilized Flame

Abstract

It is well known that bluff objects placed in combustible high -speed flows stabilize flames. To investigate and characterize the blow out limits for a V -gutter st abilized flame, a Combustion Wind Tunnel Facility (CWTF) was utilized in an attempt to determine a possible footprint or unique attribute of approaching a blowout condition. Characterization of these limits was achieved by running the V -Gutter at a stable condition and approaching lean or rich blowout while investigating pressure oscillations, CH fluctuations, temperature changes, flame intensity and fluctuation, and flame structure. The main findings did result in a unique footprint of either approaching lean blow out or rich blow out. While approaching lean blow out, the mean and rms CH emission and pressure both decrease, the frequency decreases, and the flame structure begins to shrink down from spanning the entire section towards the center of the te st section until the flame eventually extinguishes with the intensity of these images continually diminishing until extinction. While approaching rich blow out, mean CH emission decreases while rms CH emission increases, mean pressure increases with rms p ressure initially decreasing, but increasing again prior extinction, frequency increases, and the flame intensity diminishes, but also has an increased fluctuation of intensity.