(342g) Parametric Studies of Soot Formation, Evolution, and Oxidation in Turbulent Jet Flames

Soot contributes to many of the health and safety hazards associated with air pollution from combustion systems. Modeling soot formation behavior in turbulent flames involves several tightly coupled problems, including fluid dynamics, combustion chemistry, soot chemistry, soot particle size distributions, and turbulence behavior, all of which affect and are affected by soot formation and transport. There are significant uncertainties associated with modeling soot formation and transport in flames, which is crucial to developing accurate combustion models and predictive simulation tools.

The one-dimensional turbulence (ODT) model is an accurate and affordable alternative to direct numerical simulation (DNS), which is often computationally prohibitive for turbulent reacting flows of interest to engineers. ODT captures the full range of length and time scales in one dimension and delivers detailed statistical information on turbulent gas and particle transport. It allows simulations of soot in the late stages of a flame, which are typically inaccessible to DNS because of the high computational cost.

We present parametric simulations of experimental ethylene diffusion jet flames with a focus on soot evolution and oxidation. We implement and evaluate advanced soot chemistry and particle size distribution models, including the conditional quadrature method of moments (CQMOM). Soot formation rates, growth mechanisms, and oxidation mechanisms are varied, and gas temperature, soot volume fraction, and radiative enthalpy losses are quantified in order to evaluate the models and gain insight on the nature of soot-flame interactions in the soot oxidation regions of the flames.