شبكة التخطيط العمراني بسم الله الرحمن الرحيم
للكاتبين :
M. M. A. Abdalaal, M. F. Elrefaee, M. M. Kemry and F. R. Elwahsh
Faculty of Engineering, Al-Azhar University, Cairo, Egypt
ABSTRACT
The premixed flames have the advantage of homogeneous air fuel ratio overall the
combustion space, through which it is possible to control its emissions according to rich or
lean conditions. The nonpremixed flames can produce a range of local compositions spanning
a wide range of stoiechiometries i.e. within the combustion space; there may be regions that
are quite rich, while others may be quite lean. This aspect of nonpremixed combustion adds
considerable complexity to the problem of pollutant formation in such systems. Unfortunately
the stability limits of the premixed flames are extremely narrow. Therefore, the use of lean
premixed flames is quite handicapped.
The present work aims mainly to increase the usage of lean premixed flames by adding, in its
core, a nonpremixed flame. This will help to widen the stability limit of premixed flame as
well as reduce the usage of full energy produced by nonpremixed systems. The results show
that by adding the spray of nonpremixed flame to the premixed flame, the produced flame
mean temperatures are reduced, also the flame stability is increased and its emissions are
reduced.