Combustion and emission performance of swirling-flow single trapped vortex combustor

The swirling-flow single trapped vortex combustor (SSTVC) provides a new design approach for aviation engine combustors, showing promising potential for achieving high-temperature rises or low emissions. However, current research on it is limited to demonstrating its feasibility and lacks further investigation into its combustion organization, combustion, and emission characteristics. In this study, experiments are conducted to investigate the flow field, combustion, and emission characteristics of the SSTVC under 5 inlet reference velocities and 3 inlet temperatures. As the inlet reference velocities increase from 9.96 m/s to 14.95 m/s, noticeable changes are observed in the backflow velocity of the cavity, increasing from 33.8 m/s to 48.3 m/s. By combining the flow field structure and flame features, the combustion organization of the SSTVC is summarized. With an increase in the inlet reference velocities, the combustion efficiency remains almost unchanged initially at 95.75% and then increases to 96.55%. The outlet temperature distribution improves, with the pattern factor value decreasing from 0.23 to 0.14. The carbon monoxide emissions initially increased from 94.91 to 99.89 and then decreased to 88.80, the total unburned hydrocarbons decreased from 23.22 to 16.03, and the nitrogen oxide emissions showed no significant change. With an increase in the inlet temperature, all parameters improved, with the combustion efficiency increasing from 93.71% to 96.61%, the pattern factor decreasing from 0.26 to 0.12, and all emission parameters decreasing as well.