Applications of the addition of hydrogen peroxide solution on methane premixed combustion

Abstract

In view of practical applications, this study experimentally and numerically investigated the combustion enhancement by hydrogen peroxide solutions on the flame speed of premixed methane-air flame. The experiment uses a conical flame with the addition ($\alpha$) and purity ($\beta$) of hydrogen peroxide solution as the main parameter, ranging from $0\text{\%}<\alpha <20\text{\%}$ and $60\text{\%}<\beta <80\text{\%}$, respectively, from lean to rich. The flame speed was measured using the flame area method with the unburned gas temperature of 423 K. The numerical simulations were conducted using the FreeFlame model with detailed kinetic mechanisms. Numerical simulations showed that the flame speed increased quasi-linearly with the increase of $\alpha$ and $\beta$. Nevertheless, the experiment shows that the flame speed remains unchanged on $\beta =60\text{\%}$, while it increases on $\beta >70\text{\%}$ on various $\alpha$. The experiment and numerical simulation consistently correlated the equivalence ratio of the maximum flame speed on various $\alpha$ and $\beta$. The flame speed from the experiment was underestimated compared with the numerical simulation, presumably owing to the early decomposition of hydrogen peroxide. Finally, using a hydrogen peroxide solution with $\beta >70\text{\%}$ is advisable to increase the overall flame speed of premixed methane-air flames.