Computational fluid dynamics simulation for evaluating influence of gravitational acceleration on material extrusion

Abstract

Material extrusion (MEX), one of additive manufacturing processes, has a simple mechanism adaptable to various 3D printer systems. However, MEX still has various challenges in its fabrication accuracy and efficiency for producing parts for various purposes in industries. This study is developing a high-gravitational 3D printer by combining a MEX unit and a centrifuge. In MEX, gravitational acceleration strongly influences on the amount of material extruded from the nozzle outlet in a unit time. Furthermore, the thickness of one layer gets smaller in high gravity, resulting that the fabrication resolution gets higher. As a result, the high-gravitational MEX (HG-MEX) has a high potential to innovate the 3D printing system by enhancing the fabrication accuracy and efficiency at the same time. To evaluate the effect of high gravity on performances of MEX quantitatively, this study analyzes the fluid dynamics of material supplying process in HG-MEX based on numerical simulations. The simulation results show that the material supplying efficiency drastically enhances and the thickness of extruded material gets smaller in higher gravity up to 32G, which is in the same tendency with the experimental results.