Numerical Simulation of 3D Concrete Printing Derived from Printer Head and Printing Process (2024-04)¶

nsuring the repeatability and stability of printing process is significant for the 3D Concrete Printing (3DCP). However, the diversity of printers often leads to unpredictable printing journeys. Hence, in this study the printer head was dimensionally characterized by three factors: channel diameter, neck height, and nozzle diameter. The effects of printer head and process parameters (travel speed, extrusion flow rate, and nozzle height) on the geometry stability and shape of printed filament were investigated with computational fluid dynamics method. The results indicated that, for printing materials without coarse aggregates, extrusion methods had a negligible impact on 3DCP process. For the printer head, the nozzle diameter dominated the geometry stability while the neck height and channel diameter had little effects. A dimensionless parameter was proposed to quantitatively analyze the influences of travel speed, extrusion flow rate, and nozzle diameter. The systematic mechanical analysis indicated that the geometry instability (tearing and meandering) was controlled by the and nozzle height. Based on the above analysis, the selection principle for printing parameters was proposed to ensure a stable and repeatable printing. The research results regarding printer heads and printing parameters can greatly promise the large-scale application of 3DCP.