Flow modeling in a novel non-perfusion conical bioreactor

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Tissue Engineering

Background:

• Developing effective bioreactor systems is crucial for tissue engineering to ensure adequate nutrient and waste transport within scaffolds.
• Non-perfusion bioreactors offer simplicity but require careful design to achieve sufficient internal fluid exchange.
• Scaffold architecture significantly influences fluid dynamics and cell environment within engineered tissues.

Purpose of the Study:

• To evaluate the performance of a novel non-perfusion conical bioreactor.
• To investigate fluid flow patterns within scaffolds with 45-degree and 90-degree fiber lay down patterns.
• To assess the impact of scaffold architecture and Reynolds number on fluidic transport.

Main Methods:

• Experimental visualization of particle flow using laser illumination in a conical bioreactor.
• Numerical simulations using computational fluid dynamics (CFD) software.
• Testing at varying Reynolds numbers (Re 121, 170, 218) and scaffold porosities.

Main Results:

• The novel bioreactor design facilitates fluidic transport within scaffolds, addressing concerns of insufficient medium exchange.
• The 90-degree fiber lay down pattern demonstrated higher internal fluid velocities compared to the 45-degree pattern due to channel-like flow.
• Fluid velocities within scaffolds were generally one order of magnitude lower than inlet flow velocity, influenced by scaffold architecture and porosity.

Conclusions:

• The developed non-perfusion bioreactor is capable of achieving adequate fluidic transport within tissue engineering scaffolds.
• Scaffold fiber lay down pattern critically affects internal flow dynamics, with the 90-degree pattern being more advantageous for fluid transport.
• This design offers a promising solution for creating functional engineered tissues by optimizing the cellular microenvironment through controlled fluid dynamics.