Flow characteristics passing past an open cavity containing two mass injection slots. Application to the Trapped Vortex Combustor concept.

Reducing pollutant emissions, especially NOx, in aeroengines has received considerable attention in recent years. Conventional aeroengines continue to be optimized but should not yield viable solutions with more stringent regulations, e.g. -90% in NOx by 2050 in Europe. Therefore, studies should be focused on new burner geometries to meet the pollutant levels and investigations on new combustion modes such as Lean Premixed (LP) combustion. However, it is clear that these engine modifications need more developments to avoid hazardous issues: flashback, blow-off, high altitude relight, mechanical vibrations due to combustion instabilities. In this work, we investigate a fully annular Trapped Vortex Combustor. The stabilization mechanism is based on hot gases recirculation via an open cavity which contains a pilot flame. The latter is used to anchor a main premixed flame passing past the cavity (fig.1) [1]. This burner is designed to fully operate in LP mode.