A New Look at Nitrogen Oxides Formation in Internal Combustion Engines

The theory presented here allows forecasting of nitric oxide emissions in spark ignition engines. Following preliminary review of possibilities of obtaining the equilibrium state, as well as the basic concept of medium temperatures, the authors suggest using kinetic calculations for estimating the NO content of both unburned and burned mixtures.

After good correlation is obtained, particularly for lean mixtures, the calculation is used to determine the best combustion process by simulation on a computer.

Since experiments show an important effect of the fuel-air heterogeneity, complementary simulating work is conducted in order to define the best fuel stratification laws.