This paper describes the modifications and evolution of a thermal pulse combustion model for predicting the combustion oscillations of an aerovalved 250 kW pulse combustor incorporating a soot formation-combustion model. Validation of the model is carried out from the experimental data of an aerovalved Helmholtz type pulse combustor, where a sinusoidal air inlet mass flow coupled with pressure oscillations within the combustor is needed to model the instabilities of combustion oscillations correctly. The model is used to investigate the influence of different boundary conditions on combustion oscillations and soot production in the pulse combustor. The results identify the operating conditions for which continuous oscillations, steady flames and flame extinction occur. The results also show that for ambient temperatures of inlet air (lower than 325 K) with wall temperatures lower than 1100 K soot emission from propane firing pulse combustors is negligible.

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