Three-dimensional simulation of a rotating detonation engine in ammonia/hydrogen mixtures and oxygen-enriched air

Rotating detonation using ammonia as fuel may be a potential carbon free combustion technology for gas turbine. The detonation wave structure and flow field of a rotating detonation annular combustor are investigated by three-dimensional simulation with detailed chemistry of ammonia/hydrogen-air. The detonation properties, propagation mode, combustor performance and emission characteristics are studied by varying the equivalence ratios and hydrogen concentrations. Both the increases of the combustor pressure and the hydrogen concentration promote the chemical reaction rate of the ammonia burn and the detonation wave velocity gradually increases with increasing hydrogen proportion based on one-dimensional simulation. A stable single-rotating waves resulting in ammonia/hydrogen combustor are observed for a wide range of equivalent ratios only when the hydrogen concentration is at least 0.2. The steady run of the single rotating detonation had an optimal cycle efficiency when the hydrogen concentration is increased to a critical value of 0.3. NOx emissions are more dependent on equivalent ratios than hydrogen concentration in equivalence ratios ranging from 0.70 to 1.40.(c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

Rotating detonation using ammonia as fuel shows promise as a carbon-free combustion technology for gas turbines. Three-dimensional simulations were conducted to investigate the detonation wave structure and flow field of a rotating detonation annular combustor with ammonia/hydrogen-air chemistry. The impact of equivalence ratios and hydrogen concentrations on detonation properties, propagation mode, combustor performance, and emission characteristics was studied. It was found that increasing combustor pressure and hydrogen concentration enhanced the chemical reaction rate and detonation wave velocity. Stable single-rotating waves were observed in ammonia/hydrogen combustor for a wide range of equivalence ratios when the hydrogen concentration was at least 0.2. The optimal cycle efficiency of the single rotating detonation was achieved at a critical hydrogen concentration of 0.3. NOx emissions were more dependent on equivalence ratios rather than hydrogen concentration in the range of 0.70 to 1.40.