Morphology of wrinkles along the surface of turbulent Bunsen flames – Their amplification and advection due to the Darrieus–Landau instability (PDF)
Release Time:2025-04-30
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- Date:
- 2025-04-30
- Title of Paper:
- Morphology of wrinkles along the surface of turbulent Bunsen flames – Their amplification and advection due to the Darrieus–Landau instability (PDF)
- Journal:
- Proc Combust Inst
- Summary:
- The morphological development of wrinkles along the surface of a Bunsen flame in a weakly-turbulent flow is investigated, with turbulence added solely to disturb the flame front. The resulting flame-flow interactions are examined using a hybrid Navier–Stokes/front-tracking methodology within the context of the hydrodynamic theory. Topological markers based on the skewness of curvature are introduced to distinguish between sub- and super-critical conditions, or the absence/presence of the Darrieus–Landau instability, respectively. We show that for sub-critical conditions disturbances created along the flame surface are dampened when convected downstream along the flame front, and the flame surface is only weakly perturbed. For super-critical conditions, on the other hand, disturbances of the flame front are amplified when advected downstream leading to a highly corrugated surface and a flame brush of increasing thickness. A measure of these dramatic changes is included in the mean local stretch rate which, when properly modulated by a Markstein length, directly affects the turbulent flame speed.
- Co-author:
- Zhang M, Patyal A, Huang ZH, Matalon M
- Volume:
- 2019, 37(2): 2335-2343
- Page Number:
- 2335-2343
- Translation or Not:
- No
- Date of Publication:
- 2019-01-25