A distributed fuel injection enabled approach for two-zone combustion of methane-ammonia-air mixtures

A number of initiatives are underway to minimize greenhouse gas emissions caused by the use of hydrocarbon fuels in power generation, which is a major contributor to global climate change. Ongoing work has considered premixed combustion of methane-ammonia-air mixtures using experiments and simulations. The experimental approach utilizes a model swirl combustor setup while numerical simulations have been performed using a chemical reactor network. The combustor was evaluated for single stage operation for a range of equivalence ratios, methane/ammonia mixture ratios, and inlet air temperatures. Measurement and simulation results obtained for blowoff at rich and lean conditions indicated the expansion of the operability regime of the combustor through the use of a novel distributed fuel injection approach incorporated into the swirler module. Based on these findings, improvements to the current combustor are being made to transform it from a single stage to a two-stage combustor that operates on a rich burn, quick mix, and lean burn approach. The current chemical reactor network (CRN) framework will be updated to incorporate the two-stage combustion process. The overall goal of this work will be to explore and demonstrate means of achieving optimal combustion of ammonia-methane-air mixtures using a two-zone combustor approach to reduce NOx emissions while ensuring complete reactant conversion and associated energy release.