Laser diagnostic investigation of a confined premixed turbulent jet flame stabilized by recirculation

• Published in: Combustion and flame Vol. 243; p. 112061
• Main Authors: Severin, Michael, Lammel, Oliver, Meier, Wolfgang
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01-09-2022
• Subjects: Autoignition; Flame stabilization; High-speed PIV and PLIF; Turbulence-flame interaction; Autoignition; High-speed PIV and PLIF; Flame stabilization; Turbulence-flame interaction
• ISSN: 0010-2180; 1556-2921
• DOI: 10.1016/j.combustflame.2022.112061

A preheated premixed CH4/air jet flame was operated in an optically accessible rectangular combustion chamber in order to study the flame stabilization and flame expansion mechanisms. Due to an off-center position of the jet, a pronounced lateral recirculation zone had formed in the combustion chamber which stabilized the lifted flame by mixing burned and unburned gases in the shear layer. Simultaneous single shot measurements of the flow field by particle image velocimetry (PIV), of OH by planar laser induced fluorescence (PLIF) and of heat release by OH chemiluminescence imaging from two directions were performed at a frame rate of 5 kHz. The image sequences provided a detailed insight into the interaction between the flow field and the flame, particularly into the effects of the vortices that developed in the shear layer between the jet and the recirculation zone. Special interest was devoted to the role of autoignition and turbulent flame propagation near the flame base.