Computational fluid dynamics (CFD) simulation of spray drying for encapsulation of avocado seed extract

This study presents a Computational Fluid Dynamics (CFD) approach for modeling the spray drying method for the encapsulation of avocado seed extract. The CFD simulation predicted the particle size of the encapsulated product. An emulsion containing 10% w/w arabic gum and 5% w/w avocado seed extract with water as the solvent was injected into the spray dryer. The drying air temperature was varied at 140°C and 170°C with a flow rate of 6.7 m/s. The geometry of the spray dryer chamber was tubular-conical with a length of 520 mm and a tube diameter of 150 mm. The injection was conducted from the upper side at an angle of 68,9°. The spray drying unit was simulated using Ansys Fluent 2024R2 student version. The secondary particle phase was modeled using the Eulerian-Lagrangian Discrete Phase Model (DPM). The standard k-ϵ model was used to compute the three-dimensional unsteady flow area. The simulation predicted the average particle size at the outlet of the spray dryer chamber. These simulation results were validated with experiments conducted under the same input and operational conditions. The simulation results indicate average particle diameters of 3,328 μm and 2,349 μm for drying air temperatures of 140°C and 170°C, respectively. The simulation results were validated by experimental work with discrepancies of 1.41% and 0.89%.