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Volume 2: Turbo Expo 2005, 2005
The present experimental study focuses on flame characteristics and turbulent flame speeds of lean premixed flames typical for stationary gas turbines. Measurements were performed in a generic combustor at a preheating temperature of 673 K, pressures up to 14.4 bars (absolute), a bulk velocity of 40 m/s, and an equivalence ratio in the range of 0.43–0 ...
Griebel, P. +5 more
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The present experimental study focuses on flame characteristics and turbulent flame speeds of lean premixed flames typical for stationary gas turbines. Measurements were performed in a generic combustor at a preheating temperature of 673 K, pressures up to 14.4 bars (absolute), a bulk velocity of 40 m/s, and an equivalence ratio in the range of 0.43–0 ...
Griebel, P. +5 more
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Turbulent Flame Speeds of Premixed Supersonic Flame Kernels
Flow, Turbulence and Combustion, 2018It is unclear whether turbulent flame speed scalings established in low speed regimes are applicable to supersonic flames. To investigate this question, the canonical flame kernel is investigated in a scramjet-like channel having a one degree wall divergence. The growth, shape and internal kernel dynamics are investigated.
Bradley A. Ochs +3 more
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Flame Broadening Effects on Premixed Turbulent Flame Speed
Combustion Science and Technology, 1992Abstract Yakhot's turbulent flame speed model is extended to include the effects of scales smaller than the laminar flame thickness (δ). An expression for the turbulent flame speed (ST) as a function of the turbulence intensity (u') and turbulent Reynolds number is derived.
PAUL D. RONNEY, VICTOR YAKHOT
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Flame Speed and Self-Similar Propagation of Expanding Turbulent Premixed Flames
Physical Review Letters, 2012In this Letter we present turbulent flame speeds and their scaling from experimental measurements on constant-pressure, unity Lewis number expanding turbulent flames, propagating in nearly homogeneous isotropic turbulence in a dual-chamber, fan-stirred vessel.
Swetaprovo, Chaudhuri +3 more
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The Turbulent Flame Speed of Premixed Spherically Expanding Flames
2017Premixed syngas/air flames expanding in turbulent flow fields are investigated using large scale direct numerical simulations. A parametric analysis is performed in circular and spherical geometries for the detailed investigation of the interaction between the flame front and the turbulent flow field.
G. K. Giannakopoulos +3 more
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Flame speed characteristics of turbulent expanding flames in a rectangular channel
Combustion and Flame, 2019Abstract We present results from studies of freely expanding flames in a unique small-scale convective facility for different free-stream initial conditions, characterized by Taylor-Reynolds numbers in the range of R e λ g = 179 − 395 (using the streamwise RMS velocity component and the lateral Taylor-microscale) and an inertial ...
Dan Fries +4 more
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Investigation of a Turbulent Flame Speed Closure Approach for Premixed Flame Calculations
Combustion Science and Technology, 2000Abstract A computational model for turbulent premixed gaseous combustion is investigated, where the combustion process is modelled in terms of a single transport equation for a reaction progress variable c. Turbulent closure of the source term of the progress variable is based on a model, where the turbulent flame speed is used in an extension to a ...
Friedrich Dinkelacker
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51st AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition, 2013
T eff S has an inverse dependence upon the instantaneous, ensemble averaged flame curvature, an effect that scales with turbulence intensity and harmonic excitation amplitude. We show that this curvature dependence follows from basic application of Huygens propagation to flames with stochastic wrinkling superposed upon base curvature.
Dong-hyuk Shin, Tim Lieuwen
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T eff S has an inverse dependence upon the instantaneous, ensemble averaged flame curvature, an effect that scales with turbulence intensity and harmonic excitation amplitude. We show that this curvature dependence follows from basic application of Huygens propagation to flames with stochastic wrinkling superposed upon base curvature.
Dong-hyuk Shin, Tim Lieuwen
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Spectral formulation of turbulent flame speed with consideration of hydrodynamic instability
Physical Review E, 2011Effects of Darrieus-Landau (DL) instability on the structure and propagation of turbulent premixed flame fronts are considered. By first hypothesizing separation of time scales of instability and turbulence, we estimate whether the instability can develop in the presence of turbulence of given flow rms-velocity and integral length scale.
Swetaprovo, Chaudhuri +2 more
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Symposium (International) on Combustion, 1991
The influence of turbulence and the laminar flame velocity on the turbulent flame propagation is investigated using a single stroke compression-expansion machine with a square piston. Two cylinder walls were made of glass to allow optical access. A multiple spark gap ignition system produces a quasi two-dimensional flame.
S.E. Trautwein, A. Grudno, G. Adomeit
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The influence of turbulence and the laminar flame velocity on the turbulent flame propagation is investigated using a single stroke compression-expansion machine with a square piston. Two cylinder walls were made of glass to allow optical access. A multiple spark gap ignition system produces a quasi two-dimensional flame.
S.E. Trautwein, A. Grudno, G. Adomeit
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