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Shewaferaw S. Shibeshi, William E. Collins
Correlation of Hemorheology Parameter Hematocrit with Hemodynamic Factors and Arterial Diseases

Appl. Rheol. 20:6 (2010) 64092 (7 pages)

Blood rheology and hemodynamics models show positive correlation between hematocrit and hemodynamic factors that has implication to physiological and arterial disease processes. Blood flow is modeled by the Navier-Stokes equation and its non-Newtonian property by the Casson equation. Hematocrit dependent parameters in the Casson equation integrate the hematocrit level in the mathematical model. Then the mathematical model was linearized on a tetrahedral computational grid using the finite volume method. Results show strong correlation between hematocrit and hemodynamic factors. The determined hemodynamic factors and their strong correlation with the hematocrit provide explanation how these factors promote the atherosclerotic process in the right coronary artery at a steady flow and how influence arterial disease process.

Cite this publication as follows:
Shibeshi SS, Collins WE: Correlation of Hemorheology Parameter Hematocrit with Hemodynamic Factors and Arterial Diseases, Appl. Rheol. 20 (2010) 64092.

Shewaferaw Shibeshi, William E. Collins
The Rheology of Blood Flow in a Branched Arterial System

Appl. Rheol. 15:6 (2005) 398-405

Blood flow rheology is a complex phenomenon. Presently there is no universally agreed upon model to represent the viscous property of blood. However, under the general classification of non-Newtonian models that simulate blood behavior to different degrees of accuracy, there are many variants. The power law, Casson and Carreau models are popular non-Newtonian models and affect hemodynamics quantities under many conditions. In this study, the finite volume method is used to investigate hemodynamics predictions of each of the models. To implement the finite volume method, the computational fluid dynamics software Fluent 6.1 is used. In this numerical study the different hemorheological models are found to predict different results of hemodynamics variables which are known to impact the genesis of atherosclerosis and formation of thrombosis. The axial velocity magnitude percentage difference of up to 2 % and radial velocity difference up to 90 % is found at different sections of the T-junction geometry. The size of flow recirculation zones and their associated separation and reattachment point's locations differ for each model. The wall shear stress also experiences up to 12 % shift in the main tube. A velocity magnitude distribution of the grid cells shows that the Newtonian model is close dynamically to the Casson model while the power law model resembles the Carreau model.

Cite this publication as follows:
Shibeshi SS, Collins WE: The Rheology of Blood Flow in a Branched Arterial System, Appl. Rheol. 15 (2005) 398.


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