Results 131 to 140 of about 252,548 (168)

Non-adiabatic KPP fronts with an arbitrary Lewis number

Nonlinearity, 2005
The authors show that the KPP type thermo-diffusive systems in a shear flow and with a boundary heat loss possess travelling front solutions even when the Lewis number is different from one. The temperature profile is a ``bump'' as the temperature of the burnt material drops due to the heat loss.
Hamel, François, Ryzhik, Lenya
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Large-Lewis-Number Instabilities of Model Edge-Flames

Combustion and Flame, 2001
We examine anchored edge-flames in non-premixed combustion for which the Lewis number of the fuel is large. Steady two-dimensional solutions are constructed, both stable and unstable, by using a modified time-integration strategy. These calculations define a static detachment Damkohler number.
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Steady State Diffusion Flame Structure with Lewis Number Variations

Combustion Science and Technology, 1982
Abstract The effects of non-unity Lewis numbers of fuel and oxidizer on the structure of diffusion flames are studied for a variety of flow configurations. By using a generalized formation for the three-dimensional flame-sheet combustion, it is shown that the flame-sheet temperature is increased/decreased with decreasing/increasing Lewis number of ...
C. K. LAW, S. H. CHUNG
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Excitability in high-Lewis number premixed gas combustion

Combustion and Flame, 1997
Abstract The dynamical behavior of freely-propagating premixed gas flames in tubes is studied experimentally in the high-Lewis number (Le) regime using a mixture of butane and oxygen diluted with helium (Le ≈ 4.0). Steadily-propagating, stable flames develop traveling wave and spinning instabilities as the stoichiometry of the mixture approaches the ...
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Near-limit flame structures at low Lewis number

Combustion and Flame, 1990
The characteristics of premixed gas flames in mixtures with low Lewis numbers near flammability limits were studied experimentally using a low-gravity environment to reduce buoyant convection. The behavior of such flames was found to be dominated by diffusive-thermal instabilities.
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Traveling Fronts for the Thermo-Diffusive System with Arbitrary Lewis Numbers

Archive for Rational Mechanics and Analysis, 2009
The paper deals with a reaction-diffusion system of a special type, namely, of so-called KPP type. The definition domain of the system is cylindrical. The right hand side of the system contains a Lewis number, which is the ratio of thermal and material diffusivities.
Hamel, François, Ryzhik, Lenya
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Multi‐dimensional combustion waves for Lewis number close to one

Mathematical Methods in the Applied Sciences, 2006
AbstractThis paper is devoted to the study of multi‐dimensional travelling wave solution for a thermo‐diffusive model, describing the propagation of curved flames in an infinite cylinder. The linear dependence of the components of the reaction rate together with the existence of an ignition temperature ensure that the corresponding linearized operator ...
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Effects of Lewis Number on Scalar Variance Transport in Premixed Flames

Flow, Turbulence and Combustion, 2010
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Chakraborty, Nilanjan, Swaminathan, Nedunchezian   +1 more
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Revisiting effective Lewis number of combustible mixtures

Fuel, 2023
Lu-Qing Wang, Yun Ge, Hong-Hao Ma
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Flame Velocity of Cellular Flames at Low Lewis Numbers

Combustion Science and Technology, 2001
The flame velocity of cellular flames at low Lewis numbers is numerically studied, based on the compressible Navier-Stokes equation including a one-step chemical reaction. The flame velocity of a cellular flame is always larger than that of a plane flame and increases as the Lewis number becomes lower. When the Lewis number is unity, the flame velocity
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