In the following numerical simulations and experimental work had been used to optimize a new stepped
conical swirler that used in lean pre-mixed combustion process. Three dimensional computational models
were built-up to solve the swirling reacting flow and experimental setup was used to validate this
model. Several jet swirl angles were studied so that the developed flow structure varied as a consequence
of changing the swirler geometry. New swirl flow structures were identified and analyzed. The velocity
and temperature distribution after the swirl plate were presented for jet angles changed from 0
to 25

with step equal to 5
. The numerical model results give good agreement with the experimental results.
Well defined large swirl structures were shown by results and it is highly depend on the jet swirl angle.
The conclusion is that the jet swirl angles have a big effect not only on the temperature distribution but
also on the pressure drop across the swirler. The Swirl plat with jet angle from 10
to 15
gives the most
uniform temperature distribution and also the minimum pressure drop across the swirler.