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In this article, the existence of travelling wave solutions for
premixed laminar flames in a model of slow,"constant density"
combustion is studied. The model is governed by a simple system of
an exothermic chemical reaction in a gas, via the reaction rate
function, which is very natural, as we do not impose the
assumption of its continuity. The existence of travelling waves is
demonstrated and they are shown to be specific heteroclinic orbits
of a three dimensional system of ordinary differential equations,
connecting the unburned state points to a burned state point. The
existence of these solutions is based on some general topological
arguments in ordinary differential equations.
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