Investigating the effect of CuO[sbnd]CeO2 catalyst concentration on methane-air catalytic combustion in the presence of different atomic ratios of oxygen by molecular dynamics simulation

Abstract

Fossil fuels cause global warming and create greenhouse gases that cause irreparable environmental damage. On the other hand, because the combustion reactions are not completely done, dangerous compounds, such as nitrogen or carbon monoxide are produced which are very toxic and dangerous. As a result, innovative methods were implemented in combustion processes. One such method is to use a catalyst during the combustion process. This study used a molecular dynamics method to examine how the concentration of CuO[sbnd]CeO2 catalyst affected air-methane combustion in a helical microchannel. The results show that the maximum (Max) values of density (Dens), velocity (Velo), and temperature (Temp) in the excess oxygen (EO) state were 0.142 atoms per second, 0.35 Å/ps, and 1089 K, respectively, when the atomic ratio of CuO[sbnd]CeO2 increased from 1 % to 4 %. Subsequently, these values exhibited a declining trend. Also, the values of heat flux (HF), thermal conductivity, and combustion efficiency in 4 % catalyst reached the max values of 2038 W/m2, 1.15 W/m·K and 88 %. The results related to the max values of Dens, Velo, and Temp for the oxygen deficiency state had a similar trend and increased to the max values of 0.103 atom/Å3, 0.41 Å/ps, and 1024 K in 4 % catalyst, and then decreased by increasing the catalyst ratio of CuO[sbnd]CeO2 and reaching 10 %. The thermal behavior of nanostructure was more optimal in the deficient oxygen medium. © 2024 The Author(s)