| Summary: | 碩士 === 國立成功大學 === 機械工程研究所 === 81 === In this thesis is to investigate, with experimental and
theoretical approaches, the phenomena of spray combustion in
the stagnation-point flow field. In the experiment,
following the previous analysis of methane flames influenced
by water sprays, the burning charac- teristics and flow
structures of methane flames with complete- ly prevaporized
water sprays are investigated firstly. Then make use of the
analyses of methane flames with water sprays, we continue to
discuss the distributions of velocity fields, liquid droplet
size and themperature for a planar methane flame under the
influence of Diesel-oil sprays. In the theory, the burning
characteristics of a two-dime- nsional, steady, laminar flame
propagating in a monodispersed, dilute spray are examined by
using the matched asympototic techniques in the limit of
large activiation energy. Sample calculations are conducted
for methanol and ethanol burning in air. As Lewis number is
greater than unity, the flow stretch will reduce the flame, and
extinction occurs. As Lewis number is smaller than unity,
the flow stretch will strengthen the flame, and no
extinction occurs. The results of theory for partially
prevaporized model which Lewis number is greater than unity
agree with the one-dimensional study which is reported by Lin
et al.
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