Page 232 - IJB-10-5

International Journal of Bioprinting Effect of ingredient flow speed

Figure 5. Effect of printing speed on the width of the printed line. (A) Average width of the 3D-printed line of mashed potatoes (MP) against the average
actual printing speed, and (B) comparison of the printed width of the 3D-printed line at set Foodini printing speeds, i.e., (i) 3500 mm/min, (ii) 14,000
mm/min, and (iii) 25,000 mm/min, which correspond to average actual printing speeds of (i) 532 mm/min, (ii) 1914 mm/min, and (iii) 3082 mm/min.
Scale bars: 10 mm.

without thickening, but the experimental results reported 4.1. Governing equations for modeling fluid flow
that the actual printing speed was decreased (Figure 7A and The 3D food extrusion process is modeled based on non-
B). This observation could be attributed to the complicated Newtonian fluid flow in a pipe (Figure 8A), which is unlike
relationship displayed in Equation (IX), where the decrease most models that are designed for needle-like nozzles and
in printing speed could be the net result of interactions of capillary flow. The rationale for this basis is due to the
all parameters. difference in nozzle geometry (Figure 2A) for the Foodini
3D printers. Under the assumption that the fluid flow in
4. Discussion the capsule is steady, unidirectional, and uniform in the
This section proposes a theoretical model for the 3D food z-axis, the MP food inks are driven into the capsule at a
extrusion process in Foodini 3D printers and is segmented constant volumetric flow rate. In this study, the MP food
into three parts: (i) to discuss the flow of the fluid in a inks are assumed to be incompressible and follow laminar
pipe, (ii) to understand the food extrusion system, and (iii) flow. Under the condition that there is no slip and that the
connect the fluid flow model to the food extrusion process. pressure at the nozzle is equal to the atmospheric pressure

Figure 6. Effect of ingredient flow speed on the width of the printed line. (A) Average width of the 3D-printed line of mashed potatoes (MP) against the
ingredient flow speed, and (B) comparison of printed width of the 3D-printed line at set Foodini ingredient flow speeds, i.e., 1.3, 1.65, 3.3, and 5. Scale
bars: 10 mm.

Volume 10 Issue 5 (2024) 224 doi: 10.36922/ijb.2787