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A fully nonlinear equation for the flame front in a quasi-steady combustion model

35   0   0.0 ( 0 )
 نشر من قبل Luca Lorenzi
 تاريخ النشر 2009
  مجال البحث
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We revisit the Near Equidiffusional Flames (NEF) model introduced by Matkowsky and Sivashinsky in 1979 and consider a simplified, quasi-steady version of it. This simplification allows, near the planar front, an explicit derivation of the front equation. The latter is a pseudodifferential fully nonlinear parabolic equation of the fourth-order. First, we study the (orbital) stability of the null solution. Second, introducing a parameter $epsilon$, we rescale both the dependent and independent variables and prove rigourously the convergence to the solution of the Kuramoto-Sivashinsky equation as $epsilonto 0$.

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