Directed Air Jets
Directed Air Jets can be effective in using the kinetic energy of air-jets to dislodge material from surrounding hopper wall and provide better dispersion through turbulence generation. The effective radius of these jets is limeted to 1-2 feet. Therefore, the jets must be placed in effective locations or multiple units need to be installed on the hopper wall to avoid dead zones. These jets can be timed and pulsed to minimise gas consumption. It is critical to supply oil free, clean and dry air to avoid contamination and prevent plugging of fine nozzles.
The crucial flow region for discharge is that near the outlet, because the smaller span at this location is the most likely place for stoppages to form. Cleating this region, or part of the periphery of the orifice, is equivalent to having a larger opening that can be sufficient of the remaining contents to discharge.