Sensitivity to the Presence of the Combustion Submodel for Large Eddy Simulation of Transient Premixed Flame–Vortex Interactions

In this paper, the sensitivity of large eddy simulation (LES) to the presence of the combustion submodel was investigated for transient interactions between premixed flame fronts and toroidal vortex structures generated at the wake of a circular orifice. To this end, LES computations were run, with and without the combustion submodel, for two orifice diameters: 40 mm and 20 mm. Nonuniform unstructured grids with a cell characteristic length varying in the range of 0.5–1 mm were used. In going from the 40-mm orifice to the 20-mm orifice, both the size and velocity of the vortex increase, leading to a different regime of interaction with the flame: the vortex only wrinkles the flame front in the 40-mm case (wrinkled regime) and also disrupts the continuity of the front, giving rise to the formation of separate reaction zones (i.e., flame pockets that leave the main front), in the 20-mm case (breakthrough regime). It has been found that the impact of the combustion submodel on LES predictions is strongly dep...

[1]  N. Peters.  Laminar flamelet concepts in turbulent combustion , 1988 .

[2]  Salah S. Ibrahim,et al.  An assessment of large eddy simulations of premixed flames propagating past repeated obstacles , 2009 .

[3]  B. A. Kader.  Temperature and concentration profiles in fully turbulent boundary layers , 1981 .

[4]  Thierry Poinsot,et al.  Stretching and quenching of flamelets in premixed turbulent combustion , 1991 .

[5]  G. Russo,et al.  Large Eddy Simulation and PIV Measurements of Unsteady Premixed Flames Accelerated by Obstacles , 2009 .

[6]  K. Bray,et al.  Turbulent flows with premixed reactants , 1980 .

[7]  Martin Hulman,et al.  Raman spectroscopy of small-diameter nanotubes , 2004 .

[8]  Thierry Poinsot,et al.  Quenching processes and premixed turbulent combustion diagrams , 1991, Journal of Fluid Mechanics.

[9]  Thierry Poinsot,et al.  The evolution equation for the flame surface density in turbulent premixed combustion , 1994, Journal of Fluid Mechanics.

[10]  A numerical study of vortex interactions with flames developing from ignition kernels in lean methane/air mixtures , 2011 .

[11]  William L. Roberts,et al.  Investigation of Pre-mixed Flame-Kernel/Vortex Interactions via High-Speed Imaging , 2001 .

[12]  W. Roberts,et al.  Observations on the interaction between a premixed flame kernel and a vortex of different equivalence ratio , 2002 .

[13]  J. Driscoll,et al.  A laminar vortex interacting with a premixed flame: Measured formation of pockets of reactants , 1991 .

[14]  R. Borghi.  On the Structure and Morphology of Turbulent Premixed Flames , 1985 .

[15]  A. Di Benedetto,et al.  Large Eddy Simulation of transient premixed flame–vortex interactions in gas explosions , 2012 .

[16]  Gennaro Russo,et al.  Using Large Eddy Simulation for understanding vented gas explosions in the presence of obstacles. , 2009, Journal of hazardous materials.

[17]  Tarek Echekki,et al.  Direct numerical simulation of premixed flame kernel-vortex interactions in hydrogen-air mixtures , 2006 .

[18]  Marcus S. Day,et al.  The regime diagram for premixed flame kernel-vortex interactions—Revisited , 2010 .

[19]  W. Roberts,et al.  Effect of unsteady stretch on spark-ignited flame kernel survival , 1999 .

[20]  L. Goss,et al.  Images of the quenching of a flame by a vortex-To quantify regimes of turbulent combustion , 1993 .

[21]  C. Meneveau,et al.  A power-law flame wrinkling model for LES of premixed turbulent combustion Part I: non-dynamic formulation and initial tests , 2002 .

[22]  S. Ibrahim,et al.  Measurements and large eddy simulation of propagating premixed flames , 2006 .

[23]  D. Spalding,et al.  A calculation procedure for heat, mass and momentum transfer in three-dimensional parabolic flows , 1972 .

[24]  Characterisation of the Interaction between Toroidal Vortex Structures and Flame Front Propagation , 2006 .

[25]  T. Echekki,et al.  A regime diagram for premixed flame kernel-vortex interactions , 2007 .

[26]  H. Michel,et al.  Spectral dynamics in the B800 band of LH2 from Rhodospirillum molischianum: a single-molecule study , 2004 .

[27]  Chung King Law,et al.  Laminar flame speeds of hydrocarbon + air mixtures with hydrogen addition☆ , 1986 .

[28]  A. Di Benedetto,et al.  Laminar burning velocity of hydrogen-methane/air premixed flames , 2007 .

[29]  J. C. Rolon,et al.  Wrinkling, pocket formation, and double premixed flame interaction processes , 1998 .

[30]  Gennaro Russo,et al.  Sub-grid scale combustion models for large eddy simulation of unsteady premixed flame propagation around obstacles. , 2010, Journal of hazardous materials.

[31]  D. Lilly,et al.  A proposed modification of the Germano subgrid‐scale closure method , 1992 .

[32]  S. Ibrahim,et al.  LES Modeling of Premixed Deflagrating Flames in a Small-Scale Vented Explosion Chamber with a Series of Solid Obstructions , 2008 .

[33]  F. Ducros,et al.  A thickened flame model for large eddy simulations of turbulent premixed combustion , 2000 .