Large-Eddy Simulation of Swirl-Stabilized Spray Combustion

Large-Eddy Simulation of swirl-stabilized flow in a laboratory combustor have been per-formed for non-reacting and reacting conditions and both gas- and liquid-phase results are compared with available data. Dynamic model is employed for momentum subgrid closure in this study. Additionally, simulations with two reaction rate closures are performed and compared. Results for non-reacting case show the presence of vortex breakdown bubble (VBB) in the center-line region with two corner recirculation zones past the dump plane. Non-reacting comparisons with measurements for both mean and RMS show good agree-ment. Reacting simulations show presence of stronger but smaller VBB in the center-line region. Overall, reacting comparisons with measurements are also in reasonable agreement. Time-averaged flow visualization in form of streamlines indicate that the non-reacting flow rotates twice as much from the inflow to outflow boundary than the reacting case. Droplet data show good agreement for particle velocity profiles and reasonable trends for the SMD variation. I