TWO-PHASE FLOW LARGE EDDY SIMULATIONS OF A STAGED MULTIPOINT SWIRLING BURNER: COMPARISON BETWEEN EULER-EULER AND EULER-LAGRANGE DESCRIPTIONS

摘要

A two-staged swirling burner is numerically simulated through large eddy simulations. The impact of the liquid phase modeling approach is evaluated comparing the Eulerian and Lagrangian frameworks for two different operation points, full pilot injection and full multipoint injection. For the full multipoint injection, since the operation point is closer to a Lean Premixed Prevaporized (LPP) regime, both liquid phase models present similar flame structure (an M flame). For the full pilot injection, Eulerian and Lagrangian approaches result in different flames for equivalent boundary conditions: the Eulerian simulation produces a 'tulip' flame, while the Lagrangian spray forms a lifted flame. To assess the model sensitivity to boundary conditions parameters, complementary Lagrangian simulations are made varying injected droplets' diameter and spray angle, this time resulting in a 'tulip' flame very similar to the Eulerian one. Finally, a last Eulerian simulation is made, where the injected droplets' diameter is increased, still leading to a 'tulip' flame, showing that the strong interaction between liquid phase and flame highly impact the results.