Review paper on thermo-acoustic instabilities in a gas turbine burners – Flashback avoidance

Next generation modern aircraft gas turbine engines (GTE) should provide ultra-low emissions, higher operating efficiencies and cost-effective production and use of energy with decreased emissions at local and global levels. However, the combustors particularly developed for ultra-low NO X emission combustors being developed for aircraft gas turbine engines are more susceptible to combustion instabilities. Premixed combustion systems have the capability to meet future regulations on NO x emissions. However, premixed systems always involve the risk of flame flashback into the premixing section. From a gas turbine manufacturer’s point of view, it is required to enlarge the safe operating range, in particular with respect to flame flashback. The significance of these flashback phenomena is a strong function of fuel composition and operating conditions. In the literature, flashback along the wall boundary layer shows the most critical failure mechanism for many burner configurations using hydrogen-rich fuels. Therefore, in the past few years, Government, academia and several industries conducting extensive research in this area for the introduction of green technologies as lean fuel combustion and premixed burners in aero-engines. Therefore, this review paper focus on flashback propensity mechanisms in more detail and the conclusions are drawn as to mitigation technologies.