Local extinction and reignition mechanism in a turbulent lifted flame: a direct numerical simulation study

Shahram Karami, Mohsen Talei, Evatt R. Hawkes, Jacqueline H. Chen

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8 Citations (Scopus)


Local extinction and reignition was explored in a direct numerical simulation (DNS) dataset of a turbulent lifted flame. A lifted flame is relevant to practical combustion systems. Thirty individual extinction holes were identified as regions on the stoichiometric surface which have a product mass fraction less than a critical value. Large outwardly pushing structures caused compressive strain rates normal to the mixture-fraction iso-surface resulting to the initial creation of holes. Hole growth occurred in two phases. The edge-propagation velocity is initially negative and the fluid dynamic tangential strain rate on the hole surface is positive leading to rapid hole growth. Subsequently local compressive strain rates at the flame edge relax and the edge-flame propagation velocity switches to positive. When reignition starts the edge-propagation velocity is mainly influenced by the product-mass fraction displacement speed and exhibited a dependency on curvature and scalar dissipation rate.

Original languageEnglish
Pages (from-to)1685-1692
Number of pages8
JournalProceedings of the Combustion Institute
Issue number2
Publication statusPublished - 2017
Externally publishedYes


  • Lifted flame
  • Local extinction
  • Reignition
  • Edge flame
  • DNS

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