Characterization of the coherent structures in swirling flames stabilized in a two-staged multi-injection burner: Influence of the staging factor
Résumé
Staged multi-injection combustors seem good candidates to face flame stabilization problems (combustion instabilities, flashback, flame extinction), encountered in lean premixed prevaporized (LPP) burners. Staging procedures enable fuel distribution control while multipoint injection can lead to a fast and efficient mixing. In the present study, a laboratory-scale staged multipoint combustor is characterized using High Speed Particle Image Velocimetry and Planar Laser Induced Fluorescence measurements. It is shown that the fuel distribution strongly affects the flame stabilization processes, modifying the thermo-acoustic coupling. Furthermore, results reveal the presence of a precessing vortex core (PVC), that can lead to a better flame stabilization in particular cases.