The shape of the printed strand in extrusion-based additive manufacturing is an important factor that affects the surface roughness and the geometrical accuracy of the 3D printing fabrication. We used Computational Fluid Dynamics simulations to investigate the effect of the geometry of the extrusion nozzle on the cross-section of the printed strand. The extrusion of a single thread on a planar surface was modelled as an isothermal incompressible Newtonian fluid flow. The deposition of the strand is a creeping flow that solely depends on the geometry of the nozzle, the gap and the ratio of the extrusion speed to the printing speed. We considered three different nozzle geometries: a cylindrical nozzle, a square nozzle, and a cylindrical nozzle with a side plate extension retaining side flows. The numerical simulations provided the cross-section of the deposited strand as well as the printing force applied by the extruded material on the substrate. The side plate improved the compactness of the strand cross-section, while the square nozzle did not present any advantage as compared to the cylindrical nozzle, in the printed configuration that we considered.
|Title of host publication||Proceedings of the 18th International Conference of the european Society for Precision Engineering and Nanotechnology|
|Editors||D. Billington , R. K. Leach, D. Phillips , O. Riemer , E. Savio|
|Publisher||The European Society for Precision Engineering and Nanotechnology|
|Publication status||Published - 2018|
|Event||18th International Conference of the european Society for Precision Engineering and Nanotechnology (euspen 18) - Venice, Italy|
Duration: 4 Jun 2018 → 8 Jun 2018
|Conference||18th International Conference of the european Society for Precision Engineering and Nanotechnology (euspen 18)|
|Period||04/06/2018 → 08/06/2018|
- 3D printing
Comminal, R., Serdeczny, M. P., Pedersen, D. B., & Spangenberg, J. (2018). Numerical simulation of extrusion-based additive manufacturing - Effect of the nozzle geometry on the strand cross-section. In D. Billington , R. K. Leach, D. Phillips , O. Riemer , & E. Savio (Eds.), Proceedings of the 18th International Conference of the european Society for Precision Engineering and Nanotechnology (pp. 285-286 ). The European Society for Precision Engineering and Nanotechnology.