Modeling curvature effects in turbulent autoigniting non-premixed flames using tabulated chemistry

M. Uğur Göktolga (Corresponding author), Philip de Goey, Jeroen van Oijen

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Turbulent flames are intrinsically curved. In the presence of preferential diffusion, curvature effects either enhance or suppress molecular diffusion, depending on the diffusivity of the species and the direction of the flame curvature. When a tabulated chemistry type of modeling is employed, curvature-preferential diffusion interactions have to be taken into consideration in the construction of manifolds. In this study, we employ multistage stage flamelet generated manifolds (MuSt-FGM) method to model autoigniting non-premixed turbulent flames with preferential diffusion effects included. The conditions for the modeled flame are in MILD combustion regime. To model the above-mentioned curvature-preferential diffusion interactions, a new mixture fraction which has a non-unity Lewis number is defined and used as a new control variable in the manifold generation. 1D curved flames are simulated to create the necessary flamelets. The resulting MuSt-FGM tables are used in the simulation of 1D laminar flames, and then also applied to turbulent flames using 2D direct numerical simulations (DNS). It was observed that when the curvature effects are included in the manifold, the MuSt-FGM results agree well with the detailed chemistry results; whereas the results become unsatisfactory when the curvature effects are ignored.

Original languageEnglish
JournalProceedings of the Combustion Institute
VolumeXX
Issue numberX
DOIs
Publication statusAccepted/In press - 2020

Keywords

  • Flame curvature
  • MILD combustion
  • Multistage (MuSt) FGM
  • Preferential diffusion
  • Tabulated chemistry

Fingerprint Dive into the research topics of 'Modeling curvature effects in turbulent autoigniting non-premixed flames using tabulated chemistry'. Together they form a unique fingerprint.

Cite this