What is humming in gas turbine?

Answer 1

The formation of combustion oscillations can occur during an operation of a gas turbine burner. This is also known under the concepts of "combustion chamber humming", "combustion chamber oscillations", "combustion-induced pressure pulsations", "oscillating combustion processes". The combustion oscillations are due to an interaction between the quantity supplied per unit time of combustion air/fuel mixture flowing in the flow duct of the burner. The mixture is ignited after entry into a combustion chamber and burns in a flame, with the momentary combustion conversion in the flame. Combustion conversion designates the quantity of combustion air/fuel mixture converted per unit time during a combustion process in a flame. Pressure fluctuations in the combustion chamber, which can lead to the formation of a stable pressure oscillation, can occur due to a change in the combustion conversion. In addition to an increased production of noise, the combustion oscillations cause an increased mechanical and thermal load on walls associated with the combustion chamber and on other parts belonging to the combustion system.

Sandro Garcia