Influence of atomized oil microstructure on NO_x emission

Authors of the paper proposed bi-fractional atomization of oil as a way of reducing NO_x emission. The suggested idea was verified in two ways: using a mathematical model and by laboratory scale investigations. The mathematical model was one dimensional axisymmetric based on a kinetic scheme of combustion reactions. The temperature and velocity in the flame were assumed to be known. This model was examined for two cases of oil atomization. In the first case all droplets had the same diameter, while in the second case 10% of the mass was included in droplets with bigger diameter. Achieved, in theoretical investigations, NO_x reduction was greater than 40%. For the laboratory scale experiments authors used oil with pyridine addition simulating fuel-bound nitrogen. A special construction of burner was used, which allowed the microstructure of the atomized oil to be changed by changing the amount of the atomizing pressured air. During experiments, authors achieved about 30% reduction of NO_x emission. Both the mathematical model and experimental investigations show the possibility of the NO_x reduction using the proposed method. It was also carried out, that the oil droplet mean diameter isn't good value for characterizing the oil flame as far as NO_x emission is concerned.