Computational fluid dynamics of aggregating red blood cells in postcapillary venules

Abstract

Aggregate formation of red blood cells (RBCs) in a postcapillary venular bifurcation is investigated with three-dimensional computer simulations using the Chimera grid method. Interaction energy between the RBCs is modelled by a depletion interaction theory; RBCs are modelled as rigid oblate ellipsoids. The cell–cell interactions of RBCs are strongly dependent on vessel geometry and shear rates. The experimental data on vessel geometry, pseudoshear rates, and Dextran concentration obtained in our previous in vivo RBC aggregation study in postcapillary venules of the rat spinotrapezius muscle were used to simulate RBC aggregation. The computational results were compared to the experimental results from the in vivo study. The results show that cells have a larger tendency to form an aggregate under reduced flows. Aggregate formation also depends on the angle and location of the cells before they enter the bifurcation region. Comparisons with experimental data are discussed.

Keywords:

• Chimera grid
• red blood cell
• RBC aggregation
• depletion interaction energy
• postcapillary venule

Acknowledgements

This work was supported by NIH grants NHLBI RO1 HL52684 and HL18292. P.C. Johnson is also a Senior Scientist at La Jolla Bioengineering Institute. We thank Dr Junfeng Zhang for reading the manuscripts and critical comments.

Notes

^1. Email: [email protected]

^2. Email: [email protected]

^3. Email: [email protected]

Additional information

Notes on contributors

Sangho Kim

1 1. Email: [email protected]

Paul C. Johnson

2 2. Email: [email protected]

Aleksander S. Popel

3 3. Email: [email protected]