Numerical Study on the Occurrence and Sensitivity of a High-Frequency Instability in an Advanced Can-Annular Combustion System

Gas turbines for power generation use lean premixed flames to adhere to the strict pollutant emissions regulations. Unfortunately, this often leads to thermoacoustic instabilities. These instabilities can lead to failure of system components, flame blow-off or flashback and a reduction in efficiency. Especially the high frequency transverse...

Adverse pressure gradient flows and their influence on boundary layer flashback

Flame flashback is a failure mode in the operation of lean premixed combustion system. Due to higher flame speeds and lower quenching distances, hydrogen-rich fuel mixtures are prone to boundary layer flashback (BLF), where mixture flow speeds are low compared to the local flow velocity. Research at TU Munich (Eichler 2011) has resulted in new...

Numerical Study on the Driving and Damping of High-Frequency Instabilities in a Jet Flame Combustor

Lean premixed flames are being used in gas turbines to reduce the emission of NOx. Unfortunately, it results often in thermoacoustic instabilities. These instabilities are high amplitude pressure oscillations which cause damage to the combustion system, reduce efficiency, flame blow-off or flashback. While the cause for instabilities due to...

Combustion instabilities in combined cycle gas turbine: Analysis and modelling of the impact of operating conditions on combustion instability

With increasing discussion and legislation around emissions, gas turbines have evolved to limit their emissions, especially NOx emissions. The way of operating the gas turbine, with lean premixed combustion...

Boundary layer flashback prediction for low emissions full hydrogen gas turbine burners using flow simulation

Flame flashback is an intrinsic problem in lean premixed combustion. Due to higher flame speeds and lower quenching distances, hydrogen-rich fuel mixtures are especially prone to boundary layer flashback (BLF). Research at TU Munich (Eichler 2011, Baumgartner 2014) has resulted in new insights into the mechanism of BLF, revealing a strong...