Turbulent Flame Interactions and Applications to Bluff-Body Stabilized Flames

Abstract

Interactions between turbulent flames exist in many modern combustion devices, including land-based and aircraft gas turbine engines, jet augmenters, furnaces, and boilers. The interaction between adjacent flames can significantly alter the time-averaged structure and dynamical behavior of flames, including their heat release rate, consumption speed, thermoacoustic response, and blow-off and flash-back limits. In this presentation, we first discuss flame interaction in a realistic combustor configuration, like would be found on a power-generation gas turbine engine. Here, flame interaction can significantly alter the time-average structure of flames. Additionally, this experiment raises a number of important questions about the dynamic behavior of interacting flames. Two more fundamental experiments are discussed to address two critical issues regarding dynamic flame interaction: flow interaction and local flame area annihilation. A three bluff-body experiment is used to discuss the importance of flow interaction and hydrodynamic instability in understanding the dynamics of interacting flames. A two-burner, high-turbulence experiment is used to explore the dynamics of local flame interactions, which are the mechanism by which flame interaction drives changes in macro-level flame behavior. Finally, the presentation concludes with an outlook on future work for these experiments and what fundamental research questions need to be answered in order to predict interacting-flame behavior in real devices.

JACQUELINE O'CONNOR

The Pennsylvania State University