Eularian wall film model for predicting dynamic cell culture process to evaluate scaffold design in a perfusion bioreactor

In tissue engineering field,it is important to develop a suitable numerical model to evaluate scaffold geometry design.The experimental evaluation of the effect of each specific scaffold parameter on tissue regeneration requires large cost and long time expend.Dynamic cell culture is commonly used for generating tissues which could replace damaged tissues.A perfusion bioreactor model is developed which is able to simulate dynamic cell culture,to evaluate scaffold quality.The wall-film model is used to simulate cell attachment with the assumption that cells could be seen as liquid drops.In the process of cell attachment,the cells could impinge to a solid surface and form a liquid film which were considered as cell attached on the scaffold surface.Two types of cell-scaffold interactions were involved in numerical models including trap model and Stanton-Rutland(Cell impinge model—CIM)model.For trap model,all cells impinged the scaffold are seen as attached.For Stanton-Rutland model,four regimes of cell-scaffold interaction are involved in the cell attachment,including stick,rebound,spread,and splash,and only stick and spread are seen as attached.By comparison with two different numerical methods,the results showed that CIM model result is more related to the experimental results than trap model,which indicated that four regimes of cell-scaffold interaction occurred in cell attachment process.By evaluating two different geometry scaffold's cells seeding by these two models,the results further indicated that this model are able to use for assessing the scaffold design.