Clarification of Vortex Structure and Evaporation Process of Unsteady Spray and Analysis of Chemical Reaction of its Flame

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The special feature of the flame of unsteady spray is the generation of soot. As a consequence, it is very significant to analyze the flame characteristics under the standpoint of the chemical reaction.The analysis of this kind of flame was carried out under the following means in this term :1.The model of the flame proposed by the other researcher was applied to the calculation.2.The polycyclic aromatic hydrocarbon with 1, 2, 3 and 4 rings was calculated by use of the model of its growth proposed by the other researcher.3.CHMKIN-III was applied to the calculation of elementary reaction.4.SENKIN was used to calculate the profile of concentration of chemical species.5.The temperature profile was given by the experimental results of the steady burner flame.6.The ambient gas was air, the initial temperature was 900 [K], the initial pressure was 8.3 [MPa] and the equivalence ratio was 4.0. The combustion was kept at the constant pressure.7.N-heptane whose cetane number was 56 was referenced as the representative fuel for a CI engine. The results of this fuel was compared to that of the oxygenated fuel.The main conclusions through the means mentioned above are as follows.a)It is able to calculate the sequential processes of the consumption of n-heptane, the heat pyrolysis from n-heptane to lower unsaturated hydrocarbons, the growth to aromatic hydrocarbns and the production and consumption of main species.b)The quantity of lower unsaturated hydrocarbons in the case of oxygenated fuel decrease over 50 [%] comparing with case of n-heptane. It is notable that the decrease in the polycyclic aromatic hydrocarbons is distinguished in the case of oxygenated fuel.c)The production of polycyclic aromatic hydrocarbons of oxygenated fuel is differen due to its molecular structure.