Catalytic combustion of air-methane within a helical microchannel utilizing a molecular dynamics approach: the impact of toluene concentration with various oxygen ratios on thermal and atomic properties

This research uses molecular dynamics simulation to investigate the effects of toluene on the catalytic combustion of air-methane within a helical microchannel under varying oxygen ratios. The study focused on the thermal and atomic properties of simulated samples with varying toluene concentrations, which affected the oxygen ratios. The parameters examined included heat flux, thermal conductivity, combustion efficiency, maximum velocity, temperature, and density. The findings suggest that increasing toluene concentration may improve the nanostructure's thermal and atomic properties. Specifically, increasing the toluene concentration from 1% to 4 % in an oxygen-deficient environment increased heat flux from 2025 W/m 2 to 2035 W/m 2 , thermal conductivity from 1.09 W/m·K to 1.14 W/m·K, and combustion efficiency from 84% to 85%. Conversely, adding 10% toluene decreased these metrics to 2029 W/m 2 , 1.10 W/m·K, and 81%. In an oxygen-rich environment, increasing the toluene concentration from 1% to 4% improved heat flux, thermal conductivity, and combustion efficiency from 2019 W/m 2 , 1.06 W/m·K, and 81% to 2032 W/m 2 , 1.10 W/m·K, and 85%, respectively. However, these values declined to 2026 W/m 2 , 1.08 W/m·K, and 84% after introducing 10% toluene. Therefore, adding a small amount of toluene can enhance the combustion performance of air–methane mixtures, as it acts as an effective reactive additive in an oxygen-deficient environment.