Combustion kinetics
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چکیده
Combustion kinetics ...................................................................................................................................... 1 Physical mixing and its effects on ignition, propagation and extinction ...................................................... 2 Mixing ....................................................................................................................................................... 3 Mixture ratio specification .................................................................................................................... 3 Diffusion ............................................................................................................................................... 3 Convection ............................................................................................................................................ 4 Evaporation ............................................................................................................................................... 5 Evaporation from a planar surface ........................................................................................................ 6 Droplet evaporation............................................................................................................................... 8 Ignition and extinction ............................................................................................................................ 11 Igniter types......................................................................................................................................... 13 Propagation of non-premixed flames .......................................................................................................... 14 Gas fuel jet .............................................................................................................................................. 15 Flame length ........................................................................................................................................ 15 Condensed fuel ........................................................................................................................................ 16 Flash point (ignition) ........................................................................................................................... 16 Flame stabilisation by porous feeding: oil lamps and the candle flame ............................................. 17 Fuel sprays .......................................................................................................................................... 18 Droplet combustion ............................................................................................................................. 20 Particle combustion ............................................................................................................................. 27 Propagation of premixed flames ................................................................................................................. 29 Laminar combustion ............................................................................................................................... 29 Deflagration speed .............................................................................................................................. 31 Flame thickness ................................................................................................................................... 33 Flame stabilisation .............................................................................................................................. 34 Flame quenching ................................................................................................................................. 35 Flammability limits ............................................................................................................................. 35 Autoignition temperature .................................................................................................................... 37 Supersonic combustion ........................................................................................................................... 38 Turbulent combustion ............................................................................................................................. 41 Axisymmetric turbulent jet flames ...................................................................................................... 43 Turbulent premixed flames ................................................................................................................. 43 Chemical kinetics ........................................................................................................................................ 44 Reaction mechanism and reaction rate .................................................................................................... 44 Mass action law ................................................................................................................................... 45 Types of elementary reactions ............................................................................................................ 46 Arrhenius law ...................................................................................................................................... 47 Collision theory ................................................................................................................................... 49 Relation between rate coefficients and equilibrium constants ............................................................ 50 Kinetics of NOx formation ...................................................................................................................... 51 Catalysis .................................................................................................................................................. 52 The three-way catalytic converter ....................................................................................................... 53 Selective catalytic reduction (SCR) .................................................................................................... 53 Catalytic combustion........................................................................................................................... 54
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