Determination of rate parameters based on NH2 concentration profiles measured in ammonia-doped methane–air flames. (15th January 2018)

• Record Type: Journal Article
• Authors: Samu, Viktor; Varga, Tamás; Rahinov, Igor; Cheskis, Sergey; Turányi, Tamás
• Is Part Of: Fuel. Volume 212(2018)
• Page Start: 679
• Page End: 683
• Publication Date: 2018-01-15
• Subjects: NOx chemistry in combustion systems -- Ammonia-doped methane flame -- Burner stabilized laminar flat flame -- Mechanism optimization -- Uncertainty of rate parameters; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2017.10.019
• Languages: English
• ISSNs: 0016-2361

Abstract

Highlights: NH2 concentration profiles in NH3 -doped laminar flat methane flames were evaluated. Arrhenius parameters of reactions NH2 + H = NH + H2 and NH3 + OH = NH2 + H2 O were fitted. Direct measurements and theoretical determinations were also used as targets. The obtained mechanism gives better description of the experimental data. Temperature-dependent uncertainty bands of the rate coefficients were determined. Abstract: The experiments of Rahinov et al. ( Combust. Flame, 145 (2006) 105–116) measuring NH2 concentration profiles in methane–air laminar flat flames doped with ammonia were re-evaluated. The flames were simulated with the FlameMaster code using a modified NOx combustion mechanism of the CRECK Modeling Group. Based on local sensitivity analysis results, Arrhenius parameters A, n, E of reaction steps NH2 + H = NH + H2 and NH3 + OH = NH2 + H2 O were selected for optimization, which took into account not only the experimental data of Rahinov et al., but also related direct measurements and theoretical determinations as optimization targets. The optimized mechanism described the measured concentration profiles better than the original one, while the new rate parameter values were within the prior uncertainty limits obtained from the evaluation of literature data. The optimization process also provided new posterior uncertainty limits, which are within the prior uncertainty limits.