1997 Fiscal Year Final Research Report Summary
Effects of blood cells on the resistance to flow in microvessels
| Project/Area Number |
08650229
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Fluid engineering
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| Research Institution | Kansai University |
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Principal Investigator |
SUGIHARA-SEKI Masako Kansai University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (80150225)
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| Project Period (FY) |
1996 – 1997
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| Keywords | Microvessels / Vascular resistance / Stokes Flow / Numerical simulation / Blood cells |
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| Research Abstract |
In order to make a fluid dynamical estimate of the vascular resistance to flow in microvessels, with an emphasis on the effect of blood cells, we conducted a statistical analysis of the luminal geometry of microvessels, and numerical simulation of flow through microvessels.
1.Data analysis of the geometry of microvessels : In vivo data of the luminal geometry of microvessels showed that the cross-sectional shapes of small vessels are not circular, as assumed conventionally in the evaluation of vascular resistance, and that the shape is not uniform along the vessel axis. Quasi-periodic protrusions of endothelial cells into the lumen were observed near the nuclei, at some conditions.
2.Numerical simulation of vascular flow : A finite element method was used to analyze the flow of plasma only or plasma with blood cells, through vessels with protrusions of endothelial nuclei into the vessel lumen. It was found that the vascular resistance of non-uniform vessels is constantly larger than that of uniform tubes, and this tendency is enhanced in the presence of blood cells, due to fluid dynamical interaction between the non-uniform geometry and the blood cells.
3.Effects of blood cells : The motion of red cells in various flow patterns in small vessels was numerically analyzed, and the vascular resistance was evaluated as a function of the red cell configuration. The effect of the formation of red cell trains upstream of a white cell in capillaries was also investigated by a numerical simulation. It was found that fluid-dynamical interactions between red cells, red cells-white cells or blood cells-endothelial cells play an important role in elevation of the vascular resistance to flow in microvessels.
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