Ammonia and ammonia/hydrogen blends oxidation in a jet-stirred reactor: Experimental and numerical study

[Display omitted] •The initial oxidation of pure NH3 in JSR starts at ≈1200 K.•Addition of 30% of H2 to NH3 shifts reaction onset temperature by ≈250 K.•H2 presence enhances formation of radicals which promote NH3 oxidation.•The change of equivalence ratio has only slight effect on NH3/H2 oxidation. One of the most important problems of modern energy industry is the transition to carbon free fuels, which can mitigate the negative environmental effects. This paper presents experimental data on ammonia and ammonia/hydrogen blends oxidation in an isothermal jet-stirred reactor over the temperature of range 800–1300 K. Experiments were performed under atmospheric pressure, residence time of 1 s, various equivalence ratios, and with argon dilution at ≈0.99. It was revealed that hydrogen addition shifts the onset temperature of ammonia oxidation by about 250 K towards the lower region. A detailed chemical kinetic model which showed the best predictive capability was used to understand the effect of hydrogen addition on ammonia reactivity. It was shown that hydrogen presence results into higher concentrations of H, O and OH radicals. Moreover, these radicals start to form at lower temperatures when hydrogen is present. However, the change of the equivalence ratio has only slight effect on the temperature range of ammonia conversion.