Effects of CH₄ Content on NO Formation in One-Dimensional Adiabatic Flames Investigated by Saturated Laser-Induced Fluorescence and CHEMKIN Modeling

Abstract

Experiments applying saturated laser-induced fluorescence (LSF) technology were performed focusing on the influence of equivalence ratio, syngas mixture contents, on NO formation in H2/CO/CH4/CO2/N2/O2 premixed flat flames supplied by a heat flux burner. Experimental data were extracted to validate calculation by CHEMKIN software. Both experiments and CHEMKIN calculation draw one conclusion that NO mole fraction in CH4–air flame peaks at stoichiometric and ϕ 1.3, due to thermal NO and prompt NO routes. All mechanisms applied can well-predict the NO mole fraction at the fuel lean side but failed at the fuel rich side. NO mole fraction in syngas flame is propotional to CH4 ratio as shown in the experimental data, but all the mechanisms failed to predict it with some even having a wrong tendency. A rate of NO production and sensitivity analysis suggests that thermal and prompt NO routes play different roles in each mechanism, and modifications to mechanisms are required to improve NO concnetration predictions at CH4-containing syngas flame.

NO formation in high pressure premixed flames: Experimental results and validation of a new revised reaction mechanism

“…Bohon et al [41,42] also studied NO formation in alcohol and alkanes premixed flames at atmospheric pressure. Zhou et al [43] investigated the effect of CH4 content in syngas flames on NO formation in a premixed flat flame burner at atmospheric pressure.…”

Review and Perspectives of Novel Flue-Gas Internal Recirculation Combustion Technology for Low Nitrogen Emission: Fundamentals, Performance, Method, and Applications for Conventional Fossil Fuels and Sustainable e-Fuels

“…To meet the demands of real-world industrial production, the development of FIR burners using precise and highly efficient methods represents a burgeoning area of research for the future. Wet chemiluminescence detector measurements, , along with laser-induced fluorescence, − are currently at the forefront of research in particle image velocimetry (PIV) technology for FIR. Typically, stainless steel and quartz glass probes are utilized for gas sampling to measure local NOx concentrations.…”