Combustion noise and heat release rate measured in an aero-gas-turbine like pressurized com-bustor

To meet the targeted EU emission goals established for 2050 regarding NOx emissions, lean partially pre-evaporated spray combustion is favoured in aircraft engines. However, this kind of combustion system is prone to the formation of thermoacoustic instabilities, which can compromise the engine. Therefore, their prediction and understanding are significant to the future of aviation propulsion technology. An optimized design of a swirl burner for liquid fuel atomization and flame anchoring is presented and tested in a laboratory scale test rig that relates to a real engine operation, using diesel as a fuel and operating at elevated pressure. Explored are the dynamic data of the acoustics and the heat release rate related to thermoacoustic instabilities. With a view to nitric oxide formation the released emission from the exhaust is measured as well. Data are assembled at various pressure and power operation conditions. Classical post processing approaches, such as the power spectrum and cross-spectrum of the data are used. Non-linear analysis is applied to the data time series as well as the 0-1 chaotic test for the thermoacoustic system dynamics. The combustion dynamics appeared to be very different from the fingerprint of natural gas flames.