A wide range kinetic modeling study of PAH formation from liquid transportation fuels combustion

International audienceA new detailed chemical kinetic mechanism was herein developed to describe accurately the combustion of liquid transportation fuels (gasoline, jet-A1 and diesel fuel) as well as laboratory fuels (single components) over an extended range of equivalence ratios, temperatures, pressures and dilution levels. This mechanism is able to simultaneously reproduce PAH mole fraction profiles, ignition delay times and flame speeds for a variety of fuels. Three surrogate mixtures of n-decane, iso-octane and n-propylbenzene in different amounts were formulated to represent the above-mentioned commercial fuels based on their derived cetane numbers and threshold sooting indexes. Based on this mechanism, the impacts of fuel composition (ethylene vs. jet-A1 fuel) and reaction progress (height above the burner) on the respective importance of benzene and naphthalene formation pathways were characterized. In addition to HACA mechanism, naphthalene was found to be formed mainly from phenyl+vinylacetylene and benzyl+propargyl pathways for jet A-1 flames. A path involving dibenzofuran oxidation was also found to play a key role in naphthalene production in jet-A1 flame, highlighting the significant contribution of oxygenated compounds to PAH production

The combustion of kerosene: Experimental results and kinetic modelling using 1- to 3-component surrogate model fuels

International audienceThe oxidation of kerosene Jet-A1 and that of n-decane have been studied experimentally in a jet-stirred reactor at atmospheric pressure and constant residence time, over the high temperature range 900–1300 K, and for variable equivalence ratio (0.5≤ϕ≤2). Concentration profiles of the reactants, stable intermediates, and final products have been obtained by probe sampling followed by on-line and off-line GC analyses. The oxidation of neat n-decane and of kerosene in these conditions was modeled using a detailed kinetic reaction mechanism (209 species and 1673 reactions, most of them reversible). The present model was successfully used to simulate the structure of a fuel-rich premixed n-decane–oxygen–nitrogen flame. In the modelling, kerosene was represented by four surrogate model fuels: 100% n-decane, n-decane-n-propylbenzene (74%/26% mol), n-decane-n-propylcyclohexane (74%/26% mol), and n-decane-n-propylbenzene-n-propylcyclohexane (74%/15%/11% mol). The 3-component model fuel was the most appropriate for simulating the JSR experiments. It was also successfully used to simulate the structure of a fuel-rich premixed kerosene–oxygen–nitrogen flame

A Wide Range Kinetic Modeling Study of PAH Formation from Liquid Transportation Fuels Combustion

International audienc

Soot Particles Inception and PAH Condensation Modelling Applied in a Soot Model Utilizing a Sectional Method

International audienc

Experimental and numerical investigation of atmospheric laminar premixed n-butane flames in sooting conditions

International audienc

Jet Cooled Laser-induced fluorescence measurement of benzene, naphthalene and pyrene in methane flames. Comparison with modelling.

International audienc

Experimental and numerical investigation of atmospheric laminar premixed n-butane flames in sooting conditions

International audienc

Combustion de mélanges gaz naturel/hydrogène dans des flammes laminaires prémélangées (étude expérimentale et modélisation)

Cette- étude a pour but de valoriser la combustion de mélanges gaz naturel/hydrogène, combustible alternatif qui permettrait de réduire les émissions polluantes. L'objectif est d'acquérir des données cinétiques détaillées (température, concentrations d'espèces chimiques) sur la combustion de différents mélanges gaz naturel/hydrogène dans des flammes. L'influence de la quantité d'hydrogène, de la richesse et de la pression sur la cinétique chimique de combustion du gaz naturel a été examinée. Dix-huit flammes laminaires prémélangées CH4/C2H6/C3H8/H2/O2/N2 opérant à basse pression (0,079 atm) et à pression atmosphérique ont été étudiées. Les profils d'évolution des espèces moléculaires sont obtenus après prélèvement par microsonde et analyse par chromatographie en phase gazeuse et spectrométrie de masse couplée à la spectroscopie d'absorption infrarouge. Les profils de température sont mesurés par thermocouple recouvert. Cette base de données expérimentales a été utilisée pour développer le mécanisme chimique GDF-Kin® qui comporte 192 espèces impliquées dans 1287 réactions dont la plupart sont réversibles. Le mécanisme prédit de façon satisfaisante les profils de fraction molaire des espèces hydrocarbonées analysées, l'effet de l'hydrogène sur la cinétique d'oxydation du gaz naturel ainsi qu'un grand nombre de données globales et détaillées de la littérature (délais d'auto-inflammation, vitesses de flamme ... ). L'effet de 1 'hydrogène dépend fortement de sa quantité initiale et de la richesse, mais peu de la pression. L'hydrogène modifie les voies réactionnelles principales d'oxydation du gaz naturel, en particulier les réactions de métathèse par les atomes d'hydrogène.This study aims to promote the combustion of natural gas/hydrogen mixtures, an alternative fuel promising to reduce pollutants emission. The goal is to obtain detailed kinetic data (temperature, chemical species concentrations) on the combustion of natural gas/hydrogen blends in flames. The influence of hydrogen proportion, equivalence ratio and pressure on the natural gas combustion kinetics has been investigated. Eighteen laminar premixed CH4/C2H6/C3H8/H2/O2/N2 flames operating at low pressure (0.079 atm) and at atmospheric pressure have been studied. Evolution profiles of molecular species are obtained after microprobe sampling and analysis by gas chromatography and mass spectrometry coupled with infrared spectroscopy. Temperature profiles are measured with a coated thermocouple. This experimental database is used to develop a chemical mechanism GDF-Kin® which includes 192 species involved in 1287 reactions, most of them being reversible. The mechanism predicts with a good accuracy mole fraction profiles of hydrocarbons species analysed, the effect of hydrogen on the kinetic of gas natural oxidation as well as a large number of global and detailed data from literature (ignition delays, flame burning velocity ... ). The effect of hydrogen depends strongly on its initial concentration and on equivalence ratio but not much on pressure. Hydrogen affects main reaction paths of natura! gas oxidation, particularly abstraction reaction by hydrogen atoms.LILLE1-Bib. Electronique (590099901) / SudocSudocFranceF

Thermochemical properties of halogenated peroxy and alkoxy radicals of atmospheric interest

International audienc

Study of PAH and soot formation in laminar premixed methane flames

International audienc