An integrated experimental and numerical study of meso-scale vortex combustor dynamics

An integrated experimental and numerical study of meso-scale vortex combustor dynamics has been performed. In the first part, a series of meso-scale vortex stabilized combustors were designed and fabricated. Characterization of the combustion performance was carried out with diagnostic instruments such as FT-IR, gas chromatographer, and thermocouples. Stabilized hydrogen/air and oxygen-enriched methane/air flames can be achieved in a vortex combustor with a volume as small as 10mm³. In the second part, the swirling reacting flow in a vortex combustor was investigated numerically. The model treats the full conservation equations in three dimensions. The numerical algorithm is based on a preconditioned, density-based, finite-volume approach along with a dual-time stepping integration algorithm. Various fundamental mechanisms responsible for flame stabilization were examined systematically. The swirl-induced recirculation zone plays an important role in anchoring flame in a small volume by providing a heat source and a reduced velocity region, which prevents the flame to expand downstream. The energy conversion efficiency strongly depends on the flow evolution in the combustor. The influences of the combustor geometry on the flame dynamics were investigated.