Improvements of mixing process in a rapidly tubular flame burner

Yoldoss Chouari , Wassim Kriaa (1) , Hatem Mhiri (2) , Philippe Bournot (3)

1 Laboratoire de Mécanique des Fluides et Thermique
2 Unité de Thermique et Environnement
3 IUSTI - Institut universitaire des systèmes thermiques industriels

A three-dimensional simulation of a steady non-reactive mixing process in a rapidly mixed type tubular flame burner is carried out in order to examine the effects of the injectors' number (N= 2, 3, 4 and 6), the swirl number (Sw=0.46, 0.68, 1.05 and 1.83) and the injector arrangements (3-3 and 4-2). The mixing process is investigated by focusing on the following criterions: Particles trajectory, Central reverse zone (CRZ) and mixing layer thickness. The particles are tracked using a Lagrangian Discrete Phase Model (DPM). The numerical solutions are validated by comparing with previous experimental results. It is pertinent to note that the model predicts properly the flow field and the mixing in a rapidly tubular flame. The obtained results have generally shown, that for the same swirl number and same average axial velocity, the increase of injectors' number generates a larger reverse flow and decreases the mixing layer thickness. It is also shown that a high swirl number and same distribution of the injectors' number could significantly promote the mixing in rapidly tubular flame.

Keywords: DPM; Tubular flame burner; Mixing; Injectors' number; CFD; Mixing layer thickness

Domains: Engineering Sciences [physics]; Mechanics [physics.med-ph]; Fluids mechanics [physics.class-ph]; Engineering Sciences [physics]; Mechanics [physics.med-ph]; Thermics [physics.class-ph]; Engineering Sciences [physics]; Reactive fluid environment

Yoldoss Chouari, Wassim Kriaa, Hatem Mhiri, Philippe Bournot. Improvements of mixing process in a rapidly tubular flame burner. International Journal of Energy and Environnement, 2017, 8, pp.127 - 140. ⟨hal-01794472⟩