CFD simulation of air flow patterns in a spray dryer fitted with a rotary disk

Abstract EN

The air flow pattern in a co-current pilot plant spray dryer fitted with a rotary disk atomizer was determined experimentally and modelled numerically using Computational Fluid Dynamics (CFD) (ANSYS Fluent ) software.

The CFD simulation used a three dimensions system, Reynolds-Average Navier-Stokes equations (RANS), closed via the RNG k −ε turbulence model.

Measurements were carried out at a rotation of the atomizer (3000 rpm) and when there is no rotation using a drying air at 25 oC and air velocity at the inlet of 5 m/s without swirl.

The air flow pattern was predicted experimentally using cotton tufts and digital anemometer.

The CFD simulation predicted a downward central flowing air core surrounded by a slow recirculation zones near the walls for both conditions.

Analysis of CFD simulation revealed that rotation of atomizer resulted in a swirling motion of the central air core.

Simulations results were in good agreement with experimental data.