The present study investigates turbulence/flame/wall interaction in turbulent boundary layer combustion with varying wall surface reactivity using direct numerical simulation (DNS). The effects of combustion on the turbulent boundary layer were investigated. It was found that the hairpin vortices of the boundary layer turbulence are lifted upward, upstream of the flame, due to the combustion-induced adverse pressure gradient. Variations in wall surface reactivity rarely affect the characteristics of the boundary layer turbulence. Flame/wall interaction with varying wall surface reactivity was analyzed. The configuration of one-dimensional laminar head-on quenching was also studied for reference. Results showed that wall heat flux reduces as the wall surface reactivity enhances in both laminar and turbulent cases, with a more pronounced reduction in turbulent cases. Near the inert wall, heat release overshoots due to radical recombination, while near the reactive wall, the heat release weakens because the recombination reactions are suppressed due to the adsorption and consumption of radicals by the wall surface reactions. The influential zones of wall heat loss and surface reactions reach the logarithmic layer and buffer layer of the turbulent boundary layer, respectively. Near-wall flame quenching was also examined. In the turbulent case with high wall surface reactivity, the quenching distance was found to be larger than with inert wall, whereas in the laminar case, wall surface reactivity has no effect on the quenching distance. The analysis of local quenching characteristics showed that head-on quenching dominates in turbulent cases, and its occurrence increases as wall surface reactivity intensifies.

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• Combustion
• Turbulent boundary layers