Numerical Analysis of Hydrogen Peroxide Addition and Oxygen-Enriched Methane Combustion
Annas Fauzy, Guan‐Bang Chen, Ta‐Hui Lin
Abstract
High Resolution Image Download MS PowerPoint Slide 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.