Willard James Dodds

NASA clean catalytic combustor program

The ability of catalytic combustors to promote stable combustion of lean fuel-air mixtures with flame temperature less than 1800 K provides the potential for obtaining ultra-low nitrogen oxides emissions levels in combustion systems utilizing catalytic reactors. Another potential benefit of the use of catalytic reactors is improved combustion system life due to the reduced gas temperatures in the combustion zone. In standard combustion reactors with droplet burning, primary zone gas temperatures can reach stoichiometric flame temperature levels locally and radiation levels from the primary zone are relatively high. In a catalytic combustor the gas temperature is at the much lower flame temperature value associated with the average premixed fuel-air ratio. Other potential benefits of catalytic combustors include improved turbine life because of greatly reduced pattern factors, improved temperature profiles, and improved combustion lean stability. This paper investigates the potential for application of catalytic combustion to modern high-pressure-ratio gas turbine engine combustion systems. The specific goals for the combustion systems are given.