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In the present study, a stagnation-point two-phase flow field
is experimentally developed to investigate the influence of
etha- nol and gasoline sprays on the flow and flame
characteristics of a premixed methane flame. Using Phase
Doppler Particle Analyzer, distribution of droplet size, axial
velocity, and velocity fluc- tuation are measured in the
experiment. A thin thermocouple in- corporated with data
analysis is used for temperature measure- ments. A partially-
prevaporized gasoline spray premixed flame which is composed of
a weak blue flame zone and a strong luminous zone containing
many distinct lines of bright-yellow color, is introduced in
the study. The results show the effects of gas thermal
expansion on droplet deceleration (acceleration) in the pre-
flame (post-flame) regions. For combustion of ethanol and
gasoline sprays in methane/air mixtures, the variation of flame
temperature and position with the influence of different spray
condition is discussed. These experimental results help in
under- standing the fundamental mechanisms of spray combustion.
Besides, the above system is used to investigate the effects of
the microexplosion additive for diesel fuel. An experimental
study is performed on a premixed methane flame in which diesel
spray with and without additives. The results emphasize the
addi- tive can enhance the combustion efficiency for diesel
fuel. Fur- ther experimental investigations are being conducted
to under- stand the complex processes of droplet microexplosion.
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