I . Project title : A Novel Laser Ionization and Modeling Approach for the Determination of Soot Nucleation

III. Project background: The SERDP statement of need that led to this research project focuses on a requirement for better models of the mechanisms of soot formation in combustion. Soot and its combustion precursors present human health hazards. In the case of Army fighting vehicles, such as those powered by diesel engines, it is of interest to achieve the maximum possible power density. One way to do this is to run at high fuel/oxidizer ratios. However, this gives rise to high soot pollutant emissions. While they are important, health issues of the soot are not the only issue and are not the utmost concern during battle. High soot emission levels in combat vehicles may give rise to large target signatures, thus adversely affecting survivability. In the report of the SERDP-sponsored June 1999 American Academy of Environmental Engineers Air Quality Workshop [1], a major conclusion is that “chemical kinetics and aerosol dynamics governing formation and control of PM (particulate material such as soot) and associated HAPs (Hazardous Air Pollutants, such as PAH, Polycyclic Aromatic Hydrocarbons, which are precursors of soot) is a primary area needing research.” The report goes on to state that models which use presently available mechanisms are in need of refinements to achieve agreement with experiments and predictive capabilities. A fundamental understanding of the factors and detailed chemistry that govern the formation and destruction of soot and its precursors is important for the identification of control methods. This project centered upon the chemical kinetics mechanism.