Emissions of greenhouse and toxic gases from current combustion processes significantly contribute to the global climate crisis. Recent policies worldwide have shifted focus towards combating these emissions using clean and renewable energy sources. However, achieving carbon neutrality while meeting modern energy needs will require alternative carbon-free fuel sources for power generation turbine cycles. Ammonia-hydrogen blends have shown potential as carbon-free fuel sources, necessitating further investigation to accurately predict combustion properties like ignition delay times and species formation rates. These are critical for designing and constructing combustors for these power cycles.
This thesis explores the combustion characteristics of ammonia-hydrogen blends experimentally to develop and improve computational chemical kinetic models. Using laser absorption spectroscopy, species time histories for ammonia (NH3), water (H2O), and nitric oxide (NO) were measured with quantum cascade lasers centered at 10.39 ?m, 7.3 ?m, and 5.15 ?m, respectively. Data was collected during the decomposition of ammonia with hydrogen contents of 0%, 30%, and 50% at equivalence ratios of 0.6, 1, and 1.2 in air. Experimental conditions were generated using the University of Central Florida's high-pressure shock tube for advanced research (HiPER-STAR), with reflected shock pressures of 5, 10, and 20 bar with temperatures ranging from 1300 to 2200 K. These findings will be used to develop chemical kinetic models to predict ammonia-hydrogen chemistry, thereby advancing the development of clean energy turbine cycles.
Subith Vasu Sumathi, Committee Chair.
Read More