Numerical modeling of soot formation in a turbulent CH/air diffusion flame
Soot formation in a lifted C 2 H 4 -Air turbulent diffusion flame is studied using two different paths for soot nucleation and oxidation; by a 2D axisymmetric RANS simulation using ANSYS FLUENT 15.0 . The turbulence-chemistry interactions are modeled using two different approaches: steady laminar fl...
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Series: | International Journal of Spray and Combustion Dynamics |
Online Access: | https://doi.org/10.1177/1756827716638814 |
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doaj-b4cd997c23574d10bcd32eed0075d9832020-11-25T03:08:24ZengSAGE PublishingInternational Journal of Spray and Combustion Dynamics1756-82771756-82852016-06-01810.1177/175682771663881410.1177_1756827716638814Numerical modeling of soot formation in a turbulent CH/air diffusion flameManedhar Reddy BusupallyAshoke DeSoot formation in a lifted C 2 H 4 -Air turbulent diffusion flame is studied using two different paths for soot nucleation and oxidation; by a 2D axisymmetric RANS simulation using ANSYS FLUENT 15.0 . The turbulence-chemistry interactions are modeled using two different approaches: steady laminar flamelet approach and flamelet-generated manifold. Chemical mechanism is represented by POLIMI to study the effect of species concentration on soot formation. P1 approximation is employed to approximate the radiative transfer equation into truncated series expansion in spherical harmonics while the weighted sum of gray gases is invoked to model the absorption coefficient while the soot model accounts for nucleation, coagulation, surface growth, and oxidation. The first route for nucleation considers acetylene concentration as a linear function of soot nucleation rate, whereas the second route considers two and three ring aromatic species as function of nucleation rate. Equilibrium-based and instantaneous approach has been used to estimate the OH concentration for soot oxidation. Lee and Fenimore-Jones soot oxidation models are studied to shed light on the effect of OH on soot oxidation. Moreover, the soot-radiation interactions are also included in terms of absorption coefficient of soot. Furthermore, the soot-turbulence interactions have been invoked using a temperature/mixture fraction-based single variable PDF . Both the turbulence-chemistry interaction models are able to accurately predict the flame liftoff height, and for accurate prediction of flame length, radiative heat loss should be accounted in an accurate way. The soot-turbulence interactions are found sensitive to the PDF used in present study.https://doi.org/10.1177/1756827716638814 |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Manedhar Reddy Busupally Ashoke De |
spellingShingle |
Manedhar Reddy Busupally Ashoke De Numerical modeling of soot formation in a turbulent CH/air diffusion flame International Journal of Spray and Combustion Dynamics |
author_facet |
Manedhar Reddy Busupally Ashoke De |
author_sort |
Manedhar Reddy Busupally |
title |
Numerical modeling of soot formation in a turbulent CH/air diffusion flame |
title_short |
Numerical modeling of soot formation in a turbulent CH/air diffusion flame |
title_full |
Numerical modeling of soot formation in a turbulent CH/air diffusion flame |
title_fullStr |
Numerical modeling of soot formation in a turbulent CH/air diffusion flame |
title_full_unstemmed |
Numerical modeling of soot formation in a turbulent CH/air diffusion flame |
title_sort |
numerical modeling of soot formation in a turbulent ch/air diffusion flame |
publisher |
SAGE Publishing |
series |
International Journal of Spray and Combustion Dynamics |
issn |
1756-8277 1756-8285 |
publishDate |
2016-06-01 |
description |
Soot formation in a lifted C 2 H 4 -Air turbulent diffusion flame is studied using two different paths for soot nucleation and oxidation; by a 2D axisymmetric RANS simulation using ANSYS FLUENT 15.0 . The turbulence-chemistry interactions are modeled using two different approaches: steady laminar flamelet approach and flamelet-generated manifold. Chemical mechanism is represented by POLIMI to study the effect of species concentration on soot formation. P1 approximation is employed to approximate the radiative transfer equation into truncated series expansion in spherical harmonics while the weighted sum of gray gases is invoked to model the absorption coefficient while the soot model accounts for nucleation, coagulation, surface growth, and oxidation. The first route for nucleation considers acetylene concentration as a linear function of soot nucleation rate, whereas the second route considers two and three ring aromatic species as function of nucleation rate. Equilibrium-based and instantaneous approach has been used to estimate the OH concentration for soot oxidation. Lee and Fenimore-Jones soot oxidation models are studied to shed light on the effect of OH on soot oxidation. Moreover, the soot-radiation interactions are also included in terms of absorption coefficient of soot. Furthermore, the soot-turbulence interactions have been invoked using a temperature/mixture fraction-based single variable PDF . Both the turbulence-chemistry interaction models are able to accurately predict the flame liftoff height, and for accurate prediction of flame length, radiative heat loss should be accounted in an accurate way. The soot-turbulence interactions are found sensitive to the PDF used in present study. |
url |
https://doi.org/10.1177/1756827716638814 |
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