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Title: Analytical Study of Shear-Thinning Fluid Flow in Direct Ink Writing Process
Abstract

As a facile and versatile additive manufacturing technology, direct ink writing (DIW) has attracted considerable interest in academia and industry to fabricate three-dimensional structures with unique properties and functionalities. However, so far, the physical phenomena during the DIW process are not revealed in detail, leaving a research gap between the physical experiments and the underlying theories. Here, we presented a comprehensive simulation study of non-Newtonian ink flow during the DIW process. We used the computational fluid dynamics (CFD) method and revealed the shear-thinning behavior during the extrusion process. Different nozzle geometry models were adopted in the simulation. The advantages and drawbacks of each syringe-nozzle geometry were analyzed. In addition, the ink shear stress and velocity fields were investigated and compared in the case studies. Based on these investigations and analysis, we proposed an improved syringe-nozzle geometry towards high-resolution DIW. Consequently, the high-resolution and high shape fidelity DIW could enhance the DIW product performance. The results developed in this work offer valuable guidelines and could accelerate further advancement of DIW.

 
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Award ID(s):
1846863
NSF-PAR ID:
10393023
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
ASME 2022 17th International Manufacturing Science and Engineering Conference
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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