A Numerical Model for Simulating Particle Bed 3D Printing

This contribution deals with particle-bed 3D printing and presents a numerical approach to predict and optimize the printing process. The process studied here, Selective Paste Intrusion (SPI), has been successfully used to print small and medium-sized objects, but it has not been widely implemented. Before widespread adoption in the construction industry, fundamental questions regarding process optimization and paste/aggregate properties must be addressed. To optimize the process, the SPI process has been studied numerically and a computational model was developed to predict the propagation of the fluid through the particle bed. The model describes the cement paste as a Bingham fluid and the particle bed as a porous medium. In parallel, the rheology of the paste and the properties of the porous medium were investigated experimentally. The developed numerical tool was validated through printing experiments. It was shown that the tool was able to predict the final penetration depth, which is crucial for the quality of the printed component.