A Simple Model for Carbon Monoxide Oxidation in Gas Turbine Combustors†

Abstract

~~imple model for carbon monoxide in gas turbines is deyeloped. F~)t typical engine idling and full p~,,:er conditions the m~del.examlfies the effect of the parameters equivalence ratio, residence time and degree of mlxlfig on both the equilibrium carbon monoxide concentration and the approach to this level within the various regions of the combustor. The model is largely intended to be interpretive rather than predictive, but the curves presented en~ble one to q~alitatively follow re~o~te~.trends in carbon~onoxide .emission levels with the above parameters. Finally suggesnons are made for mlfilm,zlfigcarbon monoxide enussions at the idling condition.

The Influence of Turbulence/Chemical Kinetics Interaction on CO Formation

“…The gas turbine results are for equivalence ratios of 0.6 and 0.8 at low load and 0.8 at high load. The respective combustor pressures and initial temperatures at low and high load are 2.5 and 17 bar and 400 OK and 750 OK (Sheppard, 1975). The furnace results are for an equivalence ratio of 0.9, a pressure of one bar and an initial reactant temperature of 370 OK; this specification is considered typical of the flame stabilization region just downstream of a furnace burner.…”

Measurements of Mixing and Species Concentrations Within a Gas Turbine Type Combustor

“…where a and <f> are the standard deviation and mean values of the equivalence ratio at any plane along the combustor-following Fletcher and Heywood (1971) and Sheppard (1975). A high value of s implies a poor degree of fuel-air mixing, and as s tends to zero the degree of mixing improves.…”

“…The work described was originally undertaken to provide supporting data for a relatively simple modular type of model (Sheppard, 1975;de Chair, 1976). However the data are also being used in the development of a stochastic type of model (e.g.…”