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ABSTRACT: Ammonia and hydrogen are potential fuels for eliminating direct CO2 emissions considering climate change. The volumetric energy density of ammonia is 11,333 kJ/m3, and the volumetric energy density of hydrogen is 2,101 kJ/m3. The ignition energy of ammonia is 8 MJ, and the ignition energy of hydrogen is 0.08 MJ. Ammonia hydrogen mixtures in the right proportions may serve as a practical fuel if the additional challenge related to NOx emissions is addressed. Steam addition is an effective means of controlling the increases in NOx emissions resulting from either the fuel nitrogen and or the high temperatures resulting from the energy density. A computational study of turbulent ammonia + hydrogen burning with air + steam in axisymmetric opposed flow flame configurations is reported. The ANSYS Chemkin-Pro, a commercially available chemical kinetics code with the Konnov ammonia hydrogen-air reaction mechanism, is utilized. In this article, results are reported of combustion of ammonia and hydrogen with air and steam. Two mole fractions of ammonia in the fuel flow (0.9 and 1.0) and multiple mole fractions of steam (in the range 0.0 to 0.20) in the oxidizer flow in an opposed flow flame configuration at a constant mean pressure of 101 kPa and an initial fuel temperature of 298 K are considered. Six steam-air mixture temperatures in the range 473 K to 973 K for the multiple steam mole fractions are considered. The NO mass fractions decreased with the mole fraction of steam in the incoming oxidizer. Stable combustion is observed when a small amount of hydrogen is added.