Detailed Soot Modeling in Turbulent Kerosene/air Diffusion Flame: Sensitivity Analysis of Models Using Moment of Methods

Paper from the AFRC 2018 conference titled Detailed Soot Modeling in Turbulent Kerosene/air Diffusion Flame: Sensitivity Analysis of Models Using Moment of Methods

Soot formation is a complex physical process and its modeling is quite challenging. Its; complexity gets multi-fold in turbulent flows due to highly coupled interactions of turbulence,; chemistry, soot particulate dynamics and associated radiative heat transfer. In this work, a; comprehensive study is done in modeling soot formation for a turbulent Kerosene-air flame. The; current modeling approach consists of four major components namely soot chemistry modeling,; soot dynamics, turbulent-chemistry interactions and radiative heat transfer. For each component,; the state of art methodologies and tools are investigated and used. The gas phase chemistry is; represented by detailed mechanism comprising of 475 species and 4000 elementary reaction; steps. The mechanism involves formation of polycyclic aromatic hydrocarbons (PAH), used as; precursor for the soot nucleation. The soot is modeled using methods of moments with; interpolative closure, which allows the prediction of particle size distribution. The coupling of; gas phase chemistry and turbulence is modeled using steady diffusion flamelet model. The; radiation from gas and soot particles are modeled using finite volume approach with weighted; sum of gray gas model for calculation of radiative properties. The combined modeling approach; is computationally demanding, and hence, in the current framework, the modeling is done using; two equation turbulence models. The current results are compared against experimental data; from Young et al. (Proc Combust Inst 25(1):609-617, 1994). The current predictions are in; excellent match with experiments and offers a practical solution to the soot modeling for; industrial combustors.; The current computations are performed for operating pressure of 1 atm to study and investigate; the sensitivity of the current modeling approach. In an attempt to optimize the current modeling; method, a sensitivity analysis and parametric investigation is carried out for different modeling; components like the number of moments, the soot nucleation precursors and effect of sootradiation; interactions. Based on the current parametric investigation, an optimal solution strategy; is proposed which allows high fidelity soot modeling in industrial application in an efficient; manner.