SEMIANALYTICAL CORRELATIONS FOR NOX, CO, AND UHC EMISSIONS

To meet the future goals of reduced emissions produced by gas turbine combustors, a better understanding of the process of formation of vari ous pollutants is required. Both empirical and analytical approaches a re used to provide the exhaust concentrations of pollutants of interes t such as NO(x), CO, and unburned hydrocarbon with varying degrees of success. In the present investigation, an emission model that simulate s the combustor by a number of reactors representing various combustio n zones is proposed. A detailed chemical kinetic scheme was used to pr ovide a fundamental basis for the derivation of a number of expression s that simulate the reaction scheme. The model addresses the combined effects of spray evaporation and mixing in the reaction zone. The mode l validation included the utilization of a large data base obtained fo r an annular combustor of a modern turbopropulsion engine. In addition to the satisfactory agreement with the measurements, the model provid ed insight into the regions within the combustor that could be respons ible for the excessive formation of emissions. Methods to reduce the e missions may be implemented in light of such information.