Design and performance evaluation of a two-position variable geometry turbofan combustor

Extending low-NO operating range of a lean premixed–prevaporized gas turbine combustor by reaction of secondary mixtures injected into primary stage burned gas

“…The approaches for the combustion zone equivalence control are categorized into two groups. One is air staging [5], which uses variable geometry to modulate the amount of air to the combustion zone in response to the fuel flow rate, and the other is fuel staging [6], where the fuel split was modulated among multiple combustion zones or burners. Variable geometry has an inherent problem of flame stability besides the unreliability and complexity of the combustion air modulation devices.…”