Multi-phase simulation of pneumatic conveying applying a hydrodynamic hybrid model for the granular phase

Pneumatic conveying is widely used to transport granular media and bulk solids in many industrial branches. Due to the intrinsically unstable nature of dense phase pneumatic conveying, scale-up of these conveying systems is usually based on pilot scale tests. However, these tests require extensive conveying equipment and material. Two-phase continuum modelling of gas-solids flows is an emerging option of overcoming these drawbacks, also being able to simulate large systems with high particle numbers with manageable use of computational resources (in contrast to particle based methods such as DEM). By applying a hydrodynamic hybrid model for the granular phase and solving it with the research code GRAIN, we simulated pneumatic conveying of coarse granular material in the dense regime. We were able to capture essential characteristics such as plug flow, dune flow and sedimented strands and compared our results to data from own experimental tests and numerical studies from literature. Simulated pressure drop signals were also used to compile a ""phase diagram"" with reasonable results for the boundary conditions we have chosen.