Laser-induced-forward-transfer (LIFT)-based laser assisted bioprinting (LAB) has great advantages over other three-dimensional (3D) bioprinting techniques, such as none-contact, free of clogging, high precision, and good compatibility. In a typical LIFT based LAB process, a jet flow transfers the bioink from the ribbon to the substrate due to bioink bubble generation and collapse, and the printing quality is highly dependent on the jet flow regime (stable or unstable), so it is a great challenge to understand the connection between the jet flow and the printing outcomes. To tackle this challenge, a novel computational-fluid-dynamics (CFD)-based model was developed in this study to accurately describe the jet flow regime and provide guidance for optimal printing process planning, and a great agreement with the difference of less than 14% can be achieved when the length of induced jet is compared with experiments. By adopting the printing parameters recommended by the CFD model, the printing quality was greatly improved by forming a stable jet regime and organized printing patterns on the substrate, and the size of printed droplet could also be accurately predicted using the CFD simulation results through a static equilibrium model. Then, a well-organized pattern with alphabets “UT-CUMT” according to the chosen printing parameters was successfully printed. The ultimate goal of this research is to develop a solid connection between mechanical engineering community and bioprinting community by utilizing the proposed CFD model to direct the LAB process and eventually improve the quality of bioprinting.
Jie Qu (曲捷 ), Chaoran Dou (窦超然 ), Ben Xu (徐犇 ), Jianzhi Li (李建志 ), Zhonghao Rao (饶中浩 ), and Andrew Tsin , "Printing quality improvement for laser-induced forward transfer bioprinting: Numerical modeling and experimental validation", Physics of Fluids 33, 071906 (2021) https://doi.org/10.1063/5.0054675
Physics of Fluids