Molecular Structure Effects On Laminar Burning Velocities At Elevated Temperature And Pressure

Characterisation of flame development with ethanol, butanol, iso-octane, gasoline and methane in a direct-injection spark-ignition engine

“…More recently, results have been reported by Gu et al [24] for methane, by Liao et al [25] and Bradley et al [26] for ethanol, by Al-Shahrany et al [27] for iso-octane, by Jerzembeck et al [28] for gasoline, by Gu et al [29] and Sarathy et al [30] for butanol, and by Beeckmann et al [31,32] for most of these fuels. A large database of fuel structure effects was also produced by Farrell et al [33]; these authors reported data derived from thermodynamic analysis of the pressure rise from explosions in a combustion vessel (typically at 3 bar, 450 K), following the approach of Metghalchi and Keck [22]. However, their data were larger in absolute values than existing data for alkanes and aromatics by as much as 30% and the authors commented that this was due to use of different measurement techniques, e.g.…”

Turbulent burning rates of gasoline components, Part 1 – Effect of fuel structure of C6 hydrocarbons

“…The development of hydrocarbon kinetic mechanisms has occurred rapidly in the previous few decades and this, allied with improvements in u l experimental methods has resulted in better understanding of the key combustion processes taking place within the flame. Using the suggestions of previous workers [4][5][16][17][18][19] reasons for the differences in u l are given below:…”

“…Unsaturated hydrocarbons have higher burning velocities than saturated hydrocarbons. It is implicit that a lower proportion of H atoms available in the "radical pool" formed during oxidation leads to a weaker propensity for chain branching reactions to boost burn rate [4,17].…”

“…1-hexyne, 1-hexene, cyclohexene) due to the presence of the relatively weaker allylic C-H bond; this promotes an additional, kinetic, advantage to the effect of their higher T ad . There is also a larger number of the combustion routes for the break-down of alkenes/alkynes via ethyl radicals, producing extremely fast burning intermediate species, such as ethylene, vinyl radical and acetylene [4].…”

“…[1][2][3][4][5]. However, published data on the influence of hydrocarbon molecular structure on burn rate under turbulent conditions relevant to those in engine applications is virtually non-existent [6].…”