The formation of soot in actual combustion systems involves several complex processes including those related to both soot chemical kinetics and soot particle dynamics. This means that detailed soot models are required to describe the formation of this critical pollutant in such systems. Accordingly, this work involves the development of a detailed soot formation model including its implementation in OpenFOAM. The particular method of moments-based modeling approach employed is the interpolative closure one (MOMIC), which uses interpolation and extrapolation to determine from first moments those higher, fractional, and negative order ones required in such modeling. More specifically, the transport equations for each of the first three (3) moments are solved, which in turn are compared with calculations carried out using a semi-empirical soot formation model (Brookes and Moss). These soot formation related comparisons are carried out accounting for turbulent non-premixed flames, and RANS as turbulence modeling approach, including soot nucleation, coagulation, surface growth and oxidation. For modeling combustion, the steady laminar flamelet model (SLFM) is used, considering the ABF as the chemical kinetic mechanism. Radiation effects are modeled in turn using the optically thin method. For nucleation, only acetylene is considered as a soot precursor in the two-equations model, whereas in the MOMIC one, benzene is accounted for. For soot oxidation, OH and O are considered as oxidant species in both models. The numerical results obtained here are compared with the corresponding experimental ones characterizing the Adelaide jet flame EHN (ethylene-hydrogen-nitrogen) 1, accounting for soot volume fraction and temperature profiles. The influence on soot predictions of soot models parameters are particularly discussed. When compared to the experimental data available in literature, the obtained numerical results present discrepancies in accordance with the limitations of the turbulence, combustion and soot modeling approaches employed here. It is expected that detailed soot models such the one developed in this work can be utilized in future to describe the formation of soot in practical combustion systems.
Autor(es):VALENCIA, Sebastian
CELIS, Cesar
FIGUEIRA DA SILVA, Luis Fernando
Año: 2021
Título de la revista: 26th ABCM International Congress of Mechanical Engineering
Ciudad: Virtual, Online
Url: https://hal.archives-ouvertes.fr/hal-03357840/