CFD investigation on mixing in a rapidly mixed tubular flame burner

Computational fluid dynamics is used to simulate a mixing process in a rapidly mixed tubular flame burner (RTFB). The effect of several parameters such as the swirl number (S), the velocity ratio (α) and the injector arrangements (N₁ and N₂) is investigated. The mixing process is identified for a variation of the swirl number (from 0.23 to 5.44) via the Lagrangian discrete phase model. The validation of the numerical results is performed by confronting the predicted particle trajectory, the tangential velocity and the mixing layer thickness results to the experimental data. By means of the validated model, a mathematical correlation between the mixing coefficient and the different geometric parameters characterizing the RTFB is established, enabling the prediction of the mixing time for any RTFB design.