The Sivashinsky equation for corrugated flames in the large-wrinkle limit
Résumé
Sivashinsky's (1977) nonlinear integro-differential equation for the shape of corrugated 1-dimensional flames is ultimately reducible to a $2N$-body problem, involving the $2N$ complex poles of the flame slope. Thual, Frisch \& Henon (1985) derived singular linear integral equations for the pole density in the limit of large steady wrinkles $(N \gg 1)$, which they solved exactly for monocoalesced periodic fronts of highest amplitude of wrinkling and approximately otherwise. Here we solve those analytically for isolated crests, next for monocoalesced then bicoalesced periodic flame patterns, whatever the (large-) amplitudes involved. We compare the analytically predicted pole densities and flame shapes to numerical results deduced from the pole-decomposition approach. Good agreement is obtained, even for moderately large $N$s. The results are extended to give hints as to the dynamics of supplementary poles. Open problems are evoked.
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