Résumé : Numerical simulations employing two different modeling approaches are performedand validated against experimental results from a moderate or intense low-oxygendilution (MILD) system with internal recirculation. The flamelet-generated manifold (FGM)and partially stirred reactor (PaSR) closures are employed in a Reynolds-averagedNavier–Stokes (RANS) framework to carry out the numerical simulations. The resultsshow that the FGM model strongly overpredicts temperature profiles in the reactiveregion, while yielding better results along the central thermocouple. The PaSR closuresbased on a prescribed mixing time constant, Cmix, of 0.01, 0.1, and 0.5 are compared,showing that a Cmix value of 0.5 is the most appropriate choice for the cases underinvestigation. A PaSR formulation allowing local estimation of the Cmix value is found toprovide improved results for both the lateral and central thermocouples. A flame indexanalysis, used to assess the ability of FGM and PaSR to capture intense mixing of thecyclonic burner, indicates how the FGM model predicts a typical non-premixed regionafter the injection zone, contrary to the experimental observation.