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arXiv · 2212.03762

Flame-vortex interaction during turbulent side-wall quenching and its implications for flamelet manifolds

Abstract

In this study, the thermochemical state during turbulent flame-wall interaction of a stoichiometric methane-air flame is investigated using a fully resolved simulation with detailed chemistry. The turbulent side-wall quenching flame shows both head-on quenching and side-wall quenching-like behavior that significantly affects the CO formation in the near-wall region. The detailed insights from the simulation are used to evaluate a recently proposed flame (tip) vortex interaction mechanism identified from experiments on turbulent side-wall quenching. It describes the entrainment of burnt gases into the fresh gas mixture near the flame's quenching point. The flame behavior and thermochemical states observed in the simulation are similar to the phenomena observed in the experiments. A novel chemistry manifold is presented that accounts for both the effects of flame dilution due to exhaust gas recirculation in the flame vortex interaction area and enthalpy losses to the wall. The manifold is validated in an a-priori analysis using the simulation results as a reference. The incorporation of exhaust gas recirculation effects in the manifold leads to a significantly increased prediction accuracy in the near-wall regions of flame-vortex interactions.

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BibTeXRIS

Matthias Steinhausen, Thorsten Zirwes, Federica Ferraro, Arne Scholtissek, Henning Bockhorn, Christian Hasse. 2022-12-07. Flame-vortex interaction during turbulent side-wall quenching and its implications for flamelet manifolds. https://doi.org/10.1016/j.proci.2022.09.026

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