Kinetic modeling investigation on the NH3/C2H5OH/air laminar premixed burning characteristics at different equivalence ratios

Abstract

ABSTRACT Co-firing NH3 with C2H5OH in combustion systems is an excellent approach to shift toward a low-carbon society. Hence, this study conducted a numerical study on the laminar burning characteristics of NH3/C2H5OH blended fuels at all kinds of work conditions. Results denote that C2H5OH has significant effects on improving the NH3 burning intensities, such as laminar burning velocities (LBVs) and net heat release rates. The chemical and transport effects of C2H5OH play major roles in promoting the LBVs. Adding C2H5OH and changing the equivalence ratio will greatly affect the reaction rates of NH3/C2H5OH/air mixtures, which is the main reason for the changes in LBVs. Adding C2H5OH will increase the NO emission. It is suggested that an equivalence ratio of around 1.4 for NH3/C2H5OH flames is suitable after acomprehensive consideration of NO and unburned NH3 emissions. The reaction pathway analysis denotes that H and HNO play crucial parts in the NO formation, NH and NH2 play key roles in reducing the NO concentration. Finally, it is observed that compared with H2/CO/syngas/CH4, C2H5OH possesses great greatest effect on reducing NH3/air flame instability intensities.