The non-linear wave equation governing the progress of short length scale pressure perturbations across a conventional premixed flame is solved numerically. The particular acoustic disturbances considered have length scales of the same order as that of the flame and fractional amplitudes limited to O(l/#x3B8;), where #x3B8; is the dimensionless activation energy. These restrictions imply that the effects of the reaction and diffusion processes within the flame are negligible over the time scale of the passage of the pressure signals. The length scale of such a disturbance is of the order of a typical diffusion length, so the spatially varying temperature and density profile within the preheat and reaction zones must be considered (McIntosh 1989, McIntosh and Wilce 1991). However, in this work the exact steady temperature distribution, generated numerically, is used in the hyperbolic governing equations, enabling disturbances with length scales near to those of shock waves to be considered.
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