Related Experiment Video
Updated: Aug 23, 2025

Controlled Microfluidic Environment for Dynamic Investigation of Red Blood Cell Aggregation
Published on: June 4, 2015
Phenomenological characterization of blood's intermediate shear rate: a new concept for hemorheology
Hadi Tabesh1, Ali Poorkhalil2, Homa Akbari2
1Department of Life Science Engineering, Faculty of New Sciences and Technologies, University of Tehran, North Kargar Street, 14399, Tehran, Iran. hadi.tabesh@ut.ac.ir.
Abstract:
The phenomena of aggregation, breakdown, and disaggregation of the rouleaux of red blood cells (RBCs) in addition to deformability affect the human blood viscosity at different shear rates. In this study, the intermediate shear rate is introduced and defined when the effect of aggregation on the change of blood viscosity is diminished; and afterwards, the alteration in the blood viscosity is dominantly affected by the deformation of RBCs. With this respect, modeling the effective parameters on the blood shear-thinning behavior including hematocrit and plasma viscosity was performed for the two different shear regions discriminated by the proposed intermediate shear rates. The presented rheological model reflects a phenomenological approach to assess the human blood viscosity with an average error of ± 5% compared to experimental data for hematocrits between 0.299 and 0.702, subjected to various shear rates from 0.2 to 680 1/s. The temperature changes as well as biochemical effects on whole blood viscosity are characterized by the introduced plasma viscosity-dependent model. The presented comprehensive model could be used for better understanding of blood flow hemodynamics and analyzing the shear dependence of aggregation and deformability behaviors of RBCs.
Related Concept Videos
Newtonian Fluid: Problem Solving
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
Viscosity
The SI unit of viscosity is...
Blood Flow
Steady, Laminar Flow in Circular Tubes
Types of Fluids
In contrast, non-Newtonian fluids do not follow Newton's law of viscosity, and...
Couette Flow

