An improved fluidic insert, that operates on a pressurized liquid flowing through the insert (1) to generate a jet of liquid that flows from said insert and into the surrounding gaseous environment to form a spray of liquid droplets, includes: (a) a member (2) having top, front and rear outer surfaces, (b) a fluidic circuit located within this top surface and having an inlet (4), an outlet (8) and a channel (3) whose floor and sidewalls connect the inlet and outlet, and a barrier (5), located proximate the outlet, that rises from the channel floor and is configured such that: (i) it divides the channel in the region of the barrier into what are herein denoted as two power nozzles (3a, 3b), and (ii) each of these nozzles has a downstream portion that is configured so as to cause the liquid flowing from the nozzles to generate flow vortices behind the barrier (5) that are swept out of the outlet in such a manner as to control the lateral rate of spread of liquid droplets from the insert,