Modeling of Soot in the Engine Combustion Process

Spatial Distribution of Soot Volume Fraction	Modeling of Soot in the Engine Combustion Process Researchers: Sangjin Hong Dennis Assanis Margaret Wooldridge
Abstract: This study was conducted to predict the emission of pollutants such as soot and Nitrogen Oxide (NO) more accurately and to enhance understanding of the pollutant formation process. To achieve this goal, a combustion model was first developed. It was based on the fact that the reaction rate during combustion was determined by the interaction between the chemical reaction rate and the mixing rate. Also, detailed chemistry can be included in the combustion model developed. Modeling of soot focused on including the transport effect of soot particles. In a cylinder chamber, soot particles are affected by the flow motion but their transport characteristics are different from that of other species. Therefore, specific transport equations for soot are required. Using soot transport equations, soot formation and destruction rates can be predicted more accurately with spatial distribution of soot particles.
Background: Chemical reaction rate and turbulent mixing rate are important during the entire engine combustion process. Yet there is no combustion model using both the chemical reaction rate and turbulent mixing rate simultaneously. Soot particles are affected by in-cylinder flow motion. However, soot transport effect is not properly accounted for. Detailed chemistry is important to reduce uncertainty caused from the species evolution and corresponding heat release rates.
Objectives: Development of a combustion model Determine reaction rates using the interaction between chemical reaction rate and turbulent mixing rate. Develop a transition model to predict local transition phenomenon from ignition phase to turbulent combustion phase. Include detailed chemistry. Development of a soot model Include all possible soot formation and oxidation steps to predict more accurate soot formation rate. Develop soot transport equations and predict soot formation rate using soot transport equations.