Fluid flow and species transport around a Fluid flow and species transport around a

scaffoldscaffold

Centro Interdipartimentale di Fluidodinamica e Idraulica &

Department of Energy & Technology, University of Udine, Italy

F. Beux, M. Campolo, A. SoldatiF. Beux, M. Campolo, A. Soldati

Centro Interdipartimentale di Fluidodinamica e Idraulica

University of Udine - Italy

Prepared for VIVABIOCELL

Problem

The flow field controls:• Conditions for cell adhesion and growth• Transport of nutrients

34 mm

6 mm

6 mm

Φ=4 mm

Q=4 cm3/min

Re=21

Water

Objects

A. Evaluate the flow conditions inside the bioreactor to:

• Establish the actual throughput• Verify the flow homogeneity (possibility to feed

nutrients/remove catabolites, presence of dead regions)• Quantify the shear distribution (relevant for cellular growth)

B. Identify possible design modification to improve performances

Computational domain

¼ overall domain

About 450.000 FV

> 10 FV

1. Results: pressure drop & power

Maximum pressure drop in small connecting pipes(increase diameter if P is too high)

∆p=160 Pa

P=10-5 W

2. Results: flow field homogeneity (in-out)

2. Results: flow field homogeneity (corner)

2. Results: velocity in volume

Maximum velocity in small connecting pipes

Minimum velocity in the flow diffuser

3. Results: shear stress @ scaffold wall

p=8e-5÷0.03 Pa

3. Results: shear stress statistics

Average shear stress variation along scaffold

Concluding remarks

1. In-Out pressure drop depends on number and diameter of connecting pipes

2. Flow homogeneity con be improved by changing the angular position of inlet/outlet connecting pipes (45°)

3. Possibility to evaluate transport (and reaction) of species