Design and Simulation of Flow Field for Bone Tissue Engineering Scaffold Based on Triply Periodic Minimal Surface

Abstract

Abstract A novel method was proposed to design the structure of a bone tissue engineering scaffold based on triply periodic minimal surface. In this method, reverse engineering software was used to reconstruct the surface from point cloud data. This method overcomes the limitations of commercially available software packages that prevent them from generating models with complex surfaces used for bone tissue engineering scaffolds. Additionally, the fluid field of the scaffolds was simulated through a numerical method based on finite volume and the cell proliferation performance was evaluated via an in vitro experiment. The cell proliferation and the mass flow evaluated in a bioreactor further verified the flow field simulated using computational fluid dynamics. The result of this study illustrates that the pressure value drops rapidly from 0.103 Pa to 0.011 Pa in the y-axis direction and the mass flow is unevenly distributed in the outlets. The mass flow in the side outlets is observed to be approximately 24.3 times higher than that in the bottom outlets in the range 6.13 × 10−8 kg/s to 1.49 × 10−6 kg/s. Moreover, the mass flow in the bottom outlets decreases from the center to the edge, whereas the mass flow in the side outlets decreases from the top to the bottom. Importantly, although the mean value of wall shear stress is significantly more than 0.05 Pa, there is still a large area with a suitable shear stress below 0.05 Pa where most cells can proliferate well. The result shows that the inlet velocity 0.0075 m/s is suitable for cell proliferation in the scaffold. This study provides an insight into the design, analysis, and in vitro experiment of a bone tissue engineering scaffold.

Keywords

• Bone tissue engineering
• Porous scaffold
• Flow field
• Reverse engineering
• Cell proliferation