@article{phengsomphone_sahoo_chaudhury_ekkad_narayanaswamy_2026, title={Numerical Study of Premixed NH3 Flames in a Microscale Swirl Burner With an H2 Pilot Flame at Increased Pressures}, volume={1}, url={http://dx.doi.org/10.2514/6.2026-2180}, DOI={10.2514/6.2026-2180}, abstractNote={A microscale gas turbine combustor with a pilot flame design is developed and studied numerically to assess initial combustion performance of Ammonia (NH3) coupled with Hydrogen (H2) fuel. This numerical study uses CONVERGE computational fluid dynamics (CFD) software to model and simulate the reactant flow under increased pressure conditions of 1-5 atm on a structured mesh. All fuel and air are premixed, however the pilot torch is a H2 and air, and main flow is a NH3 and air mixture. Swirl blades are designed using a python script that generates airfoil shapes based on user inputs such as: 1) camber aggressiveness, location of camber apex, scaling factor, and pitch angle. All user inputs for this case then produces an effective swirl number that is not changed during this study. Simulation runs are thus parameterized by back pressure and air split ratio (ASP), and their respective flow fields are studied. The results show that the addition of H2 has raised the reactivity of the overall swirl flame, but additional combustion instability events have also been generated. NOx emissions measured at the combustor outlet are also seen to increase at increased pressures. The initial data given from these simulations will go into future design of a real life experimental microscale burner.}, journal={AIAA SCITECH 2026 Forum}, author={Phengsomphone, Adam and Sahoo, Abinash and Chaudhury, Meghna D. and Ekkad, Srinath V. and Narayanaswamy, Venkateswaran}, year={2026}, month={Jan} }