CO Emission from an Impinging Non-Premixed Flame

Area of Science:

• Combustion Science
• Chemical Engineering
• Fluid Dynamics

Background:

• Carbon monoxide (CO) is a hazardous emission from incomplete hydrocarbon fuel oxidation.
• Insufficient oxygen and cool surfaces promote CO formation in combustion systems.
• Understanding CO release mechanisms is crucial for safety and process control.

Purpose of the Study:

• To investigate the physico-thermo-chemical processes of CO release from methane/air flames impinging on a surface.
• To correlate CO emission changes with flame structure variations.
• To analyze the impact of burner-to-plate distance on CO formation.

Main Methods:

• Utilized planar laser-induced fluorescence (PLIF) for OH and CO visualization.
• Employed two-line OH PLIF thermometry for temperature measurements.
• Analyzed flame structure, CO-rich regions, heat release zones, and oxidative zones.

Main Results:

• CO emission strongly correlates with stagnating flow-driven changes in OH concentration.
• Observed distinct spatial relationships between CO, OH, and heat release zones.
• Flame structure and CO release are sensitive to burner-to-plate distance.

Conclusions:

• Surface interaction significantly alters flame structure and CO emission characteristics.
• Hydroxyl radical (OH) distribution is a key indicator for predicting CO release in impinging flames.
• The findings provide insights into managing CO emissions in practical combustion devices.