Effects of nitrogen and argon on ammonia-oxygen explosion

Abstract The primary task of this work is to clarify ammonia-oxygen explosion characteristics under nitrogen and argon atmosphere. Firstly, the flame behavior and explosion pressure are experimentally obtained. Then their correlation is revealed quantitatively. The thermal, diffusive and chemical analysis is conducted at last. The results demonstrated that the variation tendency of flame propagation velocity (FPV), maximum explosion pressure (MEP) and maximum rate of pressure rise (MRPR) is completely consistent. All index of FPV, MEP and MRPR, becomes increased and decreased with increasing equivalence ratio, continues to decrease with increasing inert gas fraction. All index of FPV, MEP and MRPR under argon atmosphere is totally larger than that under nitrogen atmosphere. By considering the state equation of ideal gas, spherically smooth flame and adiabatic compression, the flame behavior and explosion pressure under nitrogen and argon atmosphere is significantly controlled by laminar burning speed (LBS). As the inert gas fraction and equivalence ratio change, the LBS under nitrogen and argon atmosphere is significantly controlled by adiabatic flame temperature. The joint action of adiabatic flame temperature and thermal diffusivity contributes to the LBS difference.