Towards lower gas turbine emissions: Flameless distributed combustion

We report on a number of attempts in which a flameless combustor design for gas turbine applications was proposed. Through the different experimental findings of other researchers, we attempt to develop a deeper understanding of the behavior of flameless combustion systems and the major parameters impacting their emission performance. Whenever possible, we shall extend the discussion on the reported experimental/analytical results and highlight what would be considered as an interesting finding. This survey shows how the flameless combustion regime delivered on the promise of ultra-low NOx and CO emissions levels. At some operating conditions, both of NOX and CO levels fall to the single digit range (<10 ppm). The flameless phenomenon pushes the limits of flame stability to very lean fuel-air mixtures. It can be achieved with various fuels and blends and using both of the gaseous and liquid fuels, whether the combustion is in the premixed or non-premixed mode. It may be thought to offer enhanced combustion stability when compared to the lean premixed combustion systems.