Exhaust gas dilution device

The dispenser (1) has fan blades (2) integrated with a ring that is free to rotate with respect to a hub. The inclination of the blades with respect to their rotational axis Z is between 20 and 75 degrees. The blades are linked to the dispersed flux, and circular openings provided in the hub are linked to the unidirectional flux. The hub is equipped with a conical profile unit that orients gaseous flux towards the blades.