There is provided an aerosol generating device comprising: a vaporizer for heating an aerosol-forming substrate (115, 415) to form an aerosol; a plurality of air flow nozzles (121, 421); and at least one air outlet (123, 423). The air flow nozzles (121, 421) and the air outlet (123, 423) are arranged to define an air flow route (127, 427) between the air flow nozzles (121, 421) and the air outlet (123, 423). Each of the air flow nozzles (121, 421) comprises an aperture arranged to direct air towards the vicinity in a direction across the surface of the vaporizer of the vaporizer so as to manage particle size in the aerosol.