Helical pipes homogenize particle transport in pneumatic conveying

Abstract

Pneumatic conveying at moderate gas velocities can result in strongly heterogeneous particle transport, with slow particles accumulating near the bottom of the pipe while faster particles are transported above. Here, we investigate helical pipes as a passive means of homogenizing particle transport without increasing the gas velocity. CFD-DEM simulations show that the helical pipe induces swirling motion of the gas and particles, continuously redistributing particles across the pipe cross-section. This transforms the heterogeneous transport observed in a straight pipe into a more homogeneous state with a narrower particle-velocity distribution. The results demonstrate that helical pipes can maintain efficient pneumatic conveying at moderate gas velocities while reducing excessive particle velocities.