Gaseous fuel diffusion flame with low oxygen concentrations

Abstract

The present study presents an experimental investigation into combustion characteristics of Liquefied Petroleum Gas (LPG) diffusion flame at air with low oxygen concentrations. An apparatus has been developed to examine various operating conditions inside a vertical water-cooled tubular combustor. The air swirler is used as a flame holder or stabilizer. Investigated conditions covered nitrogen addition percentages (by mass) in air stream diverse from 0 to 12.5% to give low oxygen concentrations of 23.3 to 10.8%, respectively. Temperatures pattern, temperatures gradient, flame height, and emissions were utilized to evaluate the performance of LPG combustion. It inferred that by increasing the nitrogen percentages addition, the volume of the high temperature zone decreased until it disappeared at nitrogen percentage of 12.5%, therefore, the flame length was decreased. The NO emission reached its peak near the maximum temperature location. Increasing N2 percentages in air stream which consequently decreases the oxygen mass fraction or concentration, causes a reduction in the NO, O2, CO2, and CO concentrations at the combustor end.

Keywords

• Low oxygen concentration
• Diffusion flame
• Nitrogen addition