A Numerical Analysis of a Hydrogen-Fueled Trapped Vortex Combustor for RQL Applications

Abstract

Within the context of hydrogen combustion, the trapped vortex combustor (TVC) combined with a Rich-Quench-Lean (RQL) combustion strategy holds great promise for achieving ultra-low emissions and advancing sustainable combustion technologies. However, ensuring thorough and sufficient fuel-air mixing before the completion of the chemical reactions currently remains a critical challenge. This study focused on addressing this problem by exploring hydrogen’s injection temperature as the potential solution. Therefore, a combination of 1D simulations and Large-Eddy simulations were conducted. Subsequently, the role of this temperature modification on the chemical reactivity was evaluated, and the overall impact on the RQL's effectiveness was assessed. The results indicated that lowering hydrogen injection temperature from 300 K to 150 K reduced chemical reactivity by 15% to 25%. However, this reduction was insufficient to suppress or alter the combustion mode within the cavity significantly. Nevertheless, the overall temperature reduction within the TVC led to a significant decrease in NOx emissions of about 25%