Characterization and design of 3D scaffolds for biofluidic criteria

The success of tissue regeneration to a certain extent lies on the mechanical and biological environments that the scaffold provides. The former has been addressed in terms of stiffness and strength in a range of tissue engineering scenarios. The latter is often related to fluid flow capacity of facilitating nutrient delivery, waste removal, and more importantly promoting tissue remodeling. This paper aims at developing a computational fluid dynamics (CFD) analysis for scaffold characterization and design in terms of fluidic wall shear stress. A certain level of wall shear stress (WSS) is considered essential to stimulate the cell differentiation and tissue growth, thereby making load-bearing neotissue more functional. This paper will firstly examine the transporting performance of scaffold topology that was designed based upon the stiffness criterion. Then a WSS based topological design is developed by using bidirectional evolutionary structural optimization (BESO) method, where a more uniform and favorable WSS distribution can be obtained.