This paper describes a model used for the prediction of the formation of ni
trogen oxides in modifications of an industrial diffusion flame, natural ga
s fueled can combustor The flowfield inside the modified combustors is calc
ulated using a Navier-Stokes solver A fast chemistry assumption is used for
modeling the heat release. Calculated turbulence parameters are then used
for the calculation of the NOx formation rate in the post, processing mode
with the aid ol a flamelet model. The flamelet model permits the use of, de
tailed kinetic's with only minimal Computational expense. The dependence of
the NOx formation rate on the mixture fraction and scalar dissipation is c
alculated separately for each given Condition. The validation of the model
predictions is based on field test data taken earlier on several low NOx mo
difications recently applied to an industrial, reverse, flow can ope combus
tor The reduced level of NOx emissions was achieved in these modifications
by changes in the air distribution within the combustor liner. A comparison
of the predicted and measured NOx emission levels shows good potential of
the flamelet model.