Numerical Analysis of Hydrogen Peroxide Addition and Oxygen-Enriched Methane Combustion

[Image: see text] Methane (CH(4))/air lean combustion can be enhanced by increasing the concentration of the oxidizer, like oxygen (O(2)) enrichment, or adding a strong oxidant to the reactant. Hydrogen peroxide (H(2)O(2)) is a strong oxidizer that yields O(2), steam, and appreciable heat after decomposition. This study numerically investigated and compared the effects of H(2)O(2) and O(2)-enriched conditions on the adiabatic flame temperature, laminar burning velocity, flame thickness, and heat release rates of CH(4)/air combustion using the San Diego mechanism. The result showed that in fuel-lean conditions, the adiabatic flame temperature changed from H(2)O(2) addition > O(2)-enriched scenario to O(2)-enriched scenario > H(2)O(2) addition with increasing α. This transition temperature was not affected by the equivalence ratio. Adding H(2)O(2) enhanced the laminar burning velocity of the CH(4)/air lean combustion more than the O(2)-enriched scenario. The thermal and chemical effects are quantified in various H(2)O(2) additions, and it is found that the chemical effect has a noticeable contribution to the laminar burning velocity compared with the thermal effect, especially in higher H(2)O(2) addition. Further, the laminar burning velocity had a quasi-linear correlation with (OH)(max) in the flame. The maximum heat release rate was observed at lower temperatures for H(2)O(2) addition and higher temperatures for the O(2)-enriched scenario. The flame thickness was significantly reduced upon adding H(2)O(2). Finally, the dominant reaction to the heat release rate changed from the reaction of CH(3) + O ↔ CH(2)O + H in the CH(4)/air or O(2)-enriched scenario to the reaction of H(2)O(2) + OH ↔ H(2)O + HO(2) in the H(2)O(2) addition scenario.