In order to study the internal coupling between flame dynamics and vortico-acoustic waves formed during solid propellant combustion, a numerical simulation of an idealized rocket combustion chamber is carried out. The chamber is modeled as a rectangular enclosure along whose porous walls a laminar mixture of premixed reactants is uniformly injected. The mathematical model is based on the conservation equations in two space dimensions. Full account is taken of variable thermo-physical properties and finite-rate chemical kinetics. Boundary conditions are specified using the method of characteristics that accommodates the transport of entropy, vorticity, and acoustic waves. The governing equations and associated boundary conditions are solved numerically using a preconditioning technique and a dual time-stepping integration procedure. For illustrative purposes, a propane-air mixture is injected through the chamber walls in an effort to emulate the flame evolution inside a solid-propellant rocket motor under laminar conditions. First, detailed flame structures under steady-state conditions are realized. Subsequently, traveling acoustic waves are imposed at the head end. Simulation results indicate that the oscillatory velocity exhibits a multidimensional structure caused by unsteady vorticity, pressure, and flame oscillations. Accordingly, the effects of laminar premixed flame oscillations are limited to a thin region above the burning surface. This region becomes thinner as the frequency of oscillations is increased. The flowfield outside the flame zone bears a striking resemblance to recent analytical solutions obtained in a geometrically similar chamber. (C) 2003 The Combustion Institute. All rights reserved.