This research focuses on the computational analysis of polylactic acid (PLA), a biodegradable polymer widely used in 3D printing. A commercial CFD software, Ansys-Fluent, was employed to simulate the extrusion process of PLA and to understand the behavior of the deposited flow under various printing conditions, including printing height, flow rate, and travel speed. An explicit Volume of Fluid formulation was employed. The PLA was characterized based on its density, specific heat, and heat conductivity, all of which were determined to vary with temperature, as reported in the literature. Also, a comparison between Newtonian and non-Newtonian models was carried out to understand their impact on the extrusion process.

The results show that the viscosity model influences the shape of the deposited filament. Also, both travel and extrusion speeds significantly affect the quality and geometric shape of the extruded filament. Specifically, excessive speed leads to a filament width reduction and creates instability, while insufficient extrusion speed affects stability and produces less heat accumulation. Additionally, excessive printing height negatively impacts the stability of the flow and increases solidification time.

In conclusion, the present work shows a promising approach to simulate filament deposition in 3D printing. Future research will focus on validating these results through experimental studies and optimizing printing parameters to achieve high-quality printing with less material waste.