Experimental study to enhance swirl burner against boundary layer flashback

In gas turbine systems, operation stability represents the major challenge to any successful device deployment. Climate change combined with fossil fuel pollution has led to the need of considering high hydrogen content fuels, thus putting more pressure to stabilise gas turbines at operation conditions. Flashback is one of the main operation stability problems that represent a real challenge for gas turbine designers when using fast reacting fuels with high hydrogen content. One mechanism that has shown to contribute to flashback considerably is the propagation of the flame through its boundary layer. Although the latter has been studied, there are still several unknowns in its evolution through the system. Thus, boundary layer flashback of a swirling turbulent flame was investigated in a 150 kW tangential swirl burner previously characterised. To produce controlled changes to the boundary layer, the internal side of the burner was covered by woven wire steel mesh to mimic biological skin techniques in flow drag improvement. Two different wire meshes were used to study the effect of the regular roughness size on the boundary flashback. Moreover, the effects of using the wire mesh in such swirling flow with and without central air injection for reduction of other flashback phenomena were studied. The results show good enhancement of the system to boundary layer flashback, and a new map of the combustion stability of the rig has been produced.