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Micro-particle Image Velocimetry for Velocity Profile Measurements of Micro Blood Flows
Published on: April 25, 2013
Spatial variation of blood viscosity: modelling using shear fields measured by a μPIV based technique
Efstathios Kaliviotis1, Jonathan Dusting, Stavroula Balabani
1Experimental and Computational Laboratory for the Analysis of Turbulence (ECLAT), King's College London, Strand, London, United Kingdom. efstathios.kaliviotis@kcl.ac.uk
Medical Engineering & Physics
|October 15, 2010
Summary
Investigating blood viscosity, this study reveals how red blood cell aggregation impacts flow dynamics. Microstructure changes significantly alter viscosity distribution, especially at low shear rates.
Area of Science:
- Biophysics
- Rheology
- Biomedical Engineering
Background:
- Blood viscosity is crucial for cardiovascular health.
- Understanding blood's complex flow behavior, especially under shear, is essential.
- Red blood cell aggregation significantly influences blood rheology.
Purpose of the Study:
- To investigate the spatial characteristics of blood viscosity.
- To correlate blood microstructure changes with flow dynamics.
- To assess the impact of red blood cell aggregation on viscosity distribution.
Main Methods:
- Utilized a novel constitutive equation with micro-Particle Image Velocimetry (μPIV).
- Analyzed blood flow in a narrow gap plate-plate geometry at physiological hematocrit.
- Quantified velocity and aggregation characteristics using high-resolution imaging.
Main Results:
- Observed that red blood cell aggregation alters blood flow characteristics.
- Found that high aggregation leads to two-dimensional motion at low shear rates.
- Demonstrated that non-uniform microstructure correlates with viscosity distribution.
Conclusions:
- Blood viscosity is spatially variable due to microstructural non-uniformities.
- Viscosity in the flow core differs from the overall effective viscosity.
- Aggregation significantly influences the spatial distribution of blood viscosity.
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