Flow Dynamics in a Triple Swirl Burner

One of the most important milestones in gas turbine burner technology was the incorporation of swirling flows for flame stabilization. The objective of present work is the design and development of a generic fuel flexible multiple swirl burner with enhanced flashback resistance and low emissions. The burner design will allow operation in premixed and non-premixed modes with liquid and gaseous fuels. The investigated burner consists of 3 annular co-rotating swirlers: an outer radial swirler stage and two concentric axial swirler stages. Insights from the first isothermal and reactive numerical simulations for premixed methane–air combustion are being presented here. Results based on the characterization of the flow fields, temperature distribution, streamwise and azimuthal shear layer dynamics, and turbulence characteristics are presented. The velocity profiles obtained from isothermal numerical simulations are also validated by experimental results. Flame stabilization and flashback propensity are discussed with respect to the features of vortex breakdown, specifically the central recirculation zone (CRZ).