A Large-Eddy-Simulation Study of Combustion Dynamics of Bluff-Body Stabilized Flames

ABSTRACT A comprehensive numerical study is conducted to explore the dynamic behaviors of a flame stabilized by a triangular bluff body in a straight chamber. The formulation accommodates the complete set of conservation equations with turbulence closure achieved by a large eddy simulation (LES) technique. A G-equation-based level-set flamelet approach is employed to model the interactions between premixed combustion and turbulence. Both non-reacting and reacting flows are treated, with special attention given to the effect of inlet boundary conditions on the flame evolution. The flow around the bluff body consists of boundary layers, separated shear layers, a recirculation zone and a wake. Their mutual coupling, as well as interactions with acoustic motion and flame oscillation are analyzed in detail. The physical processes responsible for driving combustion instabilities and the mechanism of energy transfer from chemical reactions in the flame zone to acoustic oscillations in the bulk of the chamber are investigated systematically. Intensive resonance is found to occur between shear-layer instabilities and chamber acoustic waves, when the acoustically reflecting inlet boundary condition is enforced. The resulting complex interplay among acoustic motion, vortex shedding, and unsteady heat release forms a feedback loop and excites combustion instabilities with large flow oscillations.

[1]  Hugh Thornburg,et al.  Characteristics of Bluff Body Stabilized Turbulent Premixed Flames , 2011 .

[2]  H. Tsien.  Influence of Flame Front on the Flow Field , 2012 .

[3]  Yiliang Chen,et al.  Hybrid Unsteady RANS and PDF Method for Turbulent Non-Reactive and Reactive Flows , 2007 .

[4]  Christer Fureby,et al.  Comparison of Flamelet and Finite Rate Chemistry LES for Premixed Turbulent Combustion , 2007 .

[5]  R. Sivakumar,et al.  Experimental Investigation of the Acoustic Field in a Bluff-Body Combustor , 2008 .

[6]  Vigor Yang,et al.  Large-eddy simulations of gas-turbine swirl injector flow dynamics , 2007, Journal of Fluid Mechanics.

[7]  K. Kuo.  Recent Advances in Spray Combustion: Spray Combustion Measurements and Model Simulation , 1996 .

[8]  V. Moreau.  A self-similar premixed turbulent flame model , 2009 .

[9]  C. Fureby,et al.  On subgrid scale modeling in large eddy simulations of compressible fluid flow , 1996 .

[10]  Tim Lieuwen,et al.  Dynamics of a Longitudinally Forced, Bluff Body Stabilized Flame , 2011 .

[11]  Friedrich Dinkelacker,et al.  Large-eddy Simulation of Triangular-stabilized Lean Premixed Turbulent Flames: Quality and Error Assessment , 2012 .

[12]  S. Olovsson.  Combustion calculations on a premixed system with a bluff body flameholder , 1992 .

[13]  F. Ghirelli.  Turbulent premixed flame model based on a recent dispersion model , 2011 .

[14]  Tim Lieuwen,et al.  Combustion Instabilities In Gas Turbine Engines: Operational Experience, Fundamental Mechanisms, and Modeling , 2006 .

[15]  S. Ko,et al.  Large eddy simulation of turbulent premixed combustion flow around bluff body , 2011 .

[16]  Vigor Yang,et al.  A large-eddy simulation study of transition and flow instability in a porous-walled chamber with mass injection , 2003, Journal of Fluid Mechanics.

[17]  Claudio Bruno,et al.  The coupling of turbulence and chemistry in a premixed bluff-body flame as studied by LES , 2004 .

[18]  Vigor Yang,et al.  Large-Eddy Simulation of Combustion Dynamics of Lean-Premixed Swirl-Stabilized Combustor , 2003 .

[19]  L. Hu,et al.  Large-eddy simulation of turbulent combustion using different combustion models , 2008 .

[20]  M. Soteriou,et al.  Impact of numerics on the predictive capabilities of reacting flow LES , 2015 .

[21]  C. Fureby,et al.  Large-eddy simulations of bluff body stabilized flames , 1994 .

[22]  Lars-Erik Eriksson,et al.  Large Eddy Simulation of Bluff Body Stabilised Turbulent Premixed Flames , 1993 .

[23]  S. Osher,et al.  A level set approach for computing solutions to incompressible two-phase flow , 1994 .

[24]  S. Menon,et al.  Large Eddy Simulation of Bluff Body Stabilized Premixed Flame , 2006 .

[25]  P. Bruel,et al.  Some Specific Characteristics of Turbulence in the Reactive Wakes of Bluff Bodies , 1998 .

[26]  Christer Fureby,et al.  ILES and LES of Complex Engineering Turbulent Flows , 2006 .

[27]  Tim Lieuwen,et al.  Gas Turbine Emissions: Case Studies and Specific Technologies: Pollutant Trends and Key Drivers , 2013 .

[28]  M. Herrmann.  Numerical simulation of premixed turbulent combustion based on a level set flamelet model , 2001 .

[29]  B. Zinn,et al.  Dynamics of V-gutter-stabilized Jet-A Flames in a Single Flame Holder Combustor with Full Optical Accesss , 2009 .

[30]  A. Sjunnesson,et al.  CARS measurements and visualization of reacting flows in a bluff body stabilized flame , 1992 .

[31]  V. Yang,et al.  Analysis of Low Frequency Combustion Instabilities in a Laboratory Ramjet Combustor , 1986 .

[32]  松山新吾.  水素乱流拡散火炎のImplicit Large‐Eddy Simulation , 2016 .

[33]  Vigor Yang,et al.  Active Control of Combustion Instabilities with Distributed Actuators , 1991 .

[34]  V. Babu,et al.  Numerical Simulations of the 3D Unsteady Flow in a Bluff-Body Combustor , 2008 .

[35]  M. Soteriou,et al.  The influence of reactant temperature on the dynamics of bluff body stabilized premixed flames , 2011 .

[36]  Christer Fureby,et al.  Comparison of LES Models Applied to a Bluff Body Stabilized Flame , 2009 .

[37]  John M. Cimbala,et al.  Large structure in the far wakes of two-dimensional bluff bodies , 1988, Journal of Fluid Mechanics.

[38]  Christer Fureby,et al.  Large Eddy Simulation of Reacting Flows Applied to Bluff Body Stabilized Flames , 1995 .

[39]  L. W.,et al.  The Theory of Sound , 1898, Nature.

[40]  F. E. Marble,et al.  Experiments concerning the mechanism of flame blowoff from bluff bodies , 1983 .

[41]  Xue-Song Bai,et al.  Level-set flamelet library approach for premixed turbulent combustion , 2000 .

[42]  F. E. Marble,et al.  An analytical study of the non-steady behavior of large combustors , 1979 .

[43]  Vigor Yang,et al.  Systematic analysis of lean-premixed swirl-stabilized combustion , 2006 .

[44]  T. Lieuwen,et al.  The K-H Instability of Reacting, Acoustically Excited Bluff- Body Shear Layers , 2007 .

[45]  Tim Lieuwen,et al.  Flame-sheet dynamics of bluff-body stabilized flames during longitudinal acoustic forcing , 2009 .

[46]  A. Prasad,et al.  The instability of the shear layer separating from a bluff body , 1997, Journal of Fluid Mechanics.

[47]  C. Fureby.  A computational study of combustion instabilities due to vortex shedding , 2000 .

[48]  Santosh J. Shanbhogue,et al.  Lean blowoff of bluff body stabilized flames: Scaling and dynamics , 2009 .

[49]  S. Fujii,et al.  A Comparison of Cold and Reacting Flows Around a Bluff-Body Flame Stabilizer , 1981 .

[50]  V. Yang,et al.  Active control of nonlinear pressure oscillations in combustion chambers , 1992 .

[51]  Tim Lieuwen,et al.  Density ratio effects on reacting bluff-body flow field characteristics , 2012, Journal of Fluid Mechanics.

[52]  Prashant G. Mehta,et al.  The influence of temperature ratio on the dynamics of bluff body stabilized flames , 2006 .

[53]  J. Klingmann,et al.  Investigation of turbulence models applied to premixed combustion using a level-set flamelet library approach , 2004 .

[54]  Stephen B. Pope,et al.  Effects of combined dimension reduction and tabulation on the simulations of a turbulent premixed flame using a large-eddy simulation/probability density function method , 2014 .

[55]  Numerical Investigation of Combustion Instability in a V-Gutter Stabilized Combustor , 2013 .

[56]  P. Sagaut.  Large Eddy Simulation for Incompressible Flows , 2001 .

[57]  M. T. Mendonça,et al.  Large Eddy Simulation of Bluff Body Stabilized Turbulent Premixed Flame , 2013 .

[58]  T. Poinsot,et al.  Theoretical and numerical combustion , 2001 .

[59]  G.,et al.  TOWARD THE LARGE-EDDY SIMULATION OF COMPRESSIBLE TURBULENT FLOWS , 2022 .

[60]  C. Fureby.  A Comparison of Flamelet LES Models for Premixed Turbulent Combustion , 2006 .

[61]  Cheng-Xian Lin,et al.  Reacting Turbulent Flow and Thermal Field in a Channel With Inclined Bluff Body Flame Holders , 2010 .

[62]  V. Yang,et al.  Unsteady flow evolution in swirl injectors with radial entry. II. External excitations , 2005 .

[63]  Fang Wang,et al.  Large eddy simulation of a premixed propane turbulent bluff body flame using the Eulerian stochastic field method , 2015 .