Flame Structure and Pollutant Emission Characteristics of a Burning Kerosene Spray With Injection of Diluents

An experimental study of the effects of diluent gas injection on the structure and pollutant emissions of a kerosene spray from a twin fluid atomizer is presented. Nitrogen and carbon dioxide were used as the diluents. Flame length, radiation emission, axial and radial temperature profiles, and the radial profiles of carbon monoxide, oxygen, nitric oxide, and soot in flame gas samples were studied. The emission index, defined as the mass ratio of the rate of the species emitted to the fuel input rate, was determined from the experimental data. Results show, at a diluent injection rate approximately equal to the atomizing air flow rate, nitrogen was more effective than carbon dioxide in reducing flame length, flame radiation, and the emission indices of carbon monoxide and soot. Although both diluents increased nitric oxide emission, the effect of carbon dioxide was weaker.