Swirling jets with and without combustion

Three component velocity measurements of an isothermal confined swirling flow

“…The design of the swirler is critical to the performance of the combustor and has been discussed by many authors such as Lefebvre (10), Martin (11), Fujii et al (12), Kilik (13,14). The angle, as well as number and size of swirl vanes, dictate the amount of rotation imparted to the flow and the size of the recirculation zone.…”

Influence of side wall expansion angle and swirl generator on flow pattern in a model combustor calculated with k–ε model

“…The properties of swirl stabilized flames are affected by the specific location of the reaction zone with respect to the recirculating velocity field (Gouldin et al [4], Fujii et al [5]). It is believed that the swirl flame tends to blow off if the reaction front fails to overlap the low speed flow region near the zero axial velocity line in the recirculation zone (Tangirala et al [6]).…”

An Experimental Study of the Near-Field Mixing Characteristics of a Swirling Jet

“…Especially the formation of a recirculation zone near the orifice at high swirl rates, leading to the vortex breakdown phenomenon [40], through which the entrainment rate in the near-field region is drastically increased [54], is exploited since the middle of the last century to stabilise and control flames in furnaces and combustion chambers [32,41,43]. Despite the strong focus on combustion conditions [21,38,48,73], the stability [1,22,39] or the related recirculation zone in swirling jet flows, the case of the isothermal free jet with swirl strengths below the occurrence of reverse flow on the central axis has also attracted considerable attention [7,17,25,57,65]. The addition of mild degrees of swirl to a jet is for instance known to intensify the process of mass, momentum and heat transport [12,34], to spread and mix faster [26], and to reduce noise production in the near-field of jet exhausts [78].…”