Scaling laws for flame dynamics in periodic porous materials
Abstract
This study investigates the interaction between hydrodynamic coherent structures, heat transfer, and flame dynamics in porous media. A series of fully resolved two-dimensional numerical simulations is performed using a compressible reactive solver to model a periodic array of cylindrical obstacles. Among the key factors influencing flame dynamics at the pore scale, the effects of three parameters are examined: the Reynolds number, the interphase heat transfer, and the geometry of the medium. This analysis leads to the proposal of scaling laws describing the properties of flame dynamics. First, the effect of the Reynolds number on flame dynamics has been assessed, enabling the identification of distinct dynamical regimes. Among these, particular attention is given to an unsteady regime characterized by oscillating flames. Subsequently, the influence of interphase heat transfer and medium geometry on the characteristics of flame surface oscillations is investigated using spectral analysis. This approach allows the identification of a characteristic Strouhal number that, in the investigated regime, is nearly independent of interphase heat transfer and material geometry, indicating a coupling between the flame and vortical structures generated at the solid boundaries. In contrast, the amplitude of flame oscillations is shown to strongly depend on interphase heat transfer, decreasing as the mean Nusselt number increases—a trend confirmed across multiple configurations. This observation is further supported by results obtained from a simplified analytical model that is used to estimate the Nusselt number. Finally, the observed physical trends are confirmed through the analysis of unsteady flame dynamics in an example of inhomogeneous material, opening the perspective of extending the derived scaling laws to more complex porous burners.
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BibTeX
@misc{russo2026scaling,
title = {{Scaling laws for flame dynamics in periodic porous materials}},
author = {Alessandro Russo and Aurelien Genot and Thorsten Zirwes and Oliver T Stein and Dimosthenis Trimis and Rémi Roncen},
howpublished = {HAL},
year = {2026},
month = sep,
url = {https://hal.science/hal-05368587v3},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Scaling laws for flame dynamics in periodic porous materials
AU - Alessandro Russo
AU - Aurelien Genot
AU - Thorsten Zirwes
AU - Oliver T Stein
AU - Dimosthenis Trimis
AU - Rémi Roncen
PY - 2026
DA - 2026/09/08
PB - HAL
UR - https://hal.science/hal-05368587v3
AB - This study investigates the interaction between hydrodynamic coherent structures, heat transfer, and flame dynamics in porous media. A series of fully resolved two-dimensional numerical simulations is performed using a compressible reactive solver to model a periodic array of cylindrical obstacles. Among the key factors influencing flame dynamics at the pore scale, the effects of three parameters are examined: the Reynolds number, the interphase heat transfer, and the geometry of the medium. This analysis leads to the proposal of scaling laws describing the properties of flame dynamics. First, the effect of the Reynolds number on flame dynamics has been assessed, enabling the identification of distinct dynamical regimes. Among these, particular attention is given to an unsteady regime characterized by oscillating flames. Subsequently, the influence of interphase heat transfer and medium geometry on the characteristics of flame surface oscillations is investigated using spectral analysis. This approach allows the identification of a characteristic Strouhal number that, in the investigated regime, is nearly independent of interphase heat transfer and material geometry, indicating a coupling between the flame and vortical structures generated at the solid boundaries. In contrast, the amplitude of flame oscillations is shown to strongly depend on interphase heat transfer, decreasing as the mean Nusselt number increases—a trend confirmed across multiple configurations. This observation is further supported by results obtained from a simplified analytical model that is used to estimate the Nusselt number. Finally, the observed physical trends are confirmed through the analysis of unsteady flame dynamics in an example of inhomogeneous material, opening the perspective of extending the derived scaling laws to more complex porous burners.
ER -