ABSTRACT The effect of the external heat source on polymers’ burning behavior was studied numerically in the concurrent flow configuration combustion reactor. One dimensional coupled mathematical formulation is set to predict mass transfer and heat feedback in the “solid material– gas-phase flame” system with an external heat source applied at acertain location in the gas phase. Several mechanisms of gas-phase combustion were employed and had been tested on the burning of pyrolysis products in the burner-stabilized and free flame configurations in various conditions. Numerical results of some polymers (polyformaldehyde and polystyrene) burning are presented. External heat changed the composition of the pyrolysis products as well as heat feedback to the polymer surface and the polymer burning rate. Extra heat added to the combustion of polyoxymethylene in general increases concentrations of the undesired products such as NO (by 1–2 orders) and CO (by 3–4 orders). For polystyrene the heat source shifts the chemical equilibrium of the exhaust gas composition noticeably for some species such as CO (lean conditions, by 4 orders) and NO (by 2–3 orders), but concentrations of CO2 are essentially unaffected. Radiative heat transfer is shown to give acomparable contribution in total heat flux to the polymer.
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