Blood Rheology and Non-Newtonian Fluid Dynamics

These flashcards cover key concepts, terms, and theories related to blood rheology and the behavior of non-Newtonian fluids, as presented in the lecture notes.

Momentum Transfer

The process of transferring momentum from one object or fluid to another, significant in understanding blood flow and dynamics.

Hematocrit (HCT)

The percentage of blood volume that is occupied by red blood cells; influences blood viscosity.

Blood Viscosity

A measure of the resistance of blood to flow, sensitive to changes in hematocrit.

Non-Newtonian Fluid

A fluid whose viscosity changes under shear stress, such as blood, which does not follow Newton's law of viscosity.

Casson Model

A model to describe the flow behavior of non-Newtonian fluids that incorporates yield stress and dynamic viscosity.

Shear Stress (𝜏)

The force per unit area exerted parallel to the surface of the fluid which influences its flow behavior.

Fahraeus Effect

Describes the reduction of blood viscosity in small tubes as hematocrit decreases with decreasing diameter.

Yield Stress (𝜏𝑦)

The minimum stress required to start the flow of a material; in blood, it affects how fluids flow in vessels.

In Vitro

Refers to studies or experiments performed outside a living organism, typically in a controlled environment.

In Vivo

Refers to studies or experiments conducted within a living organism, providing real biological context.

Marginal Zone Theory

A theoretical framework used to predict hematocrit and apparent viscosity in blood flow, particularly in capillaries.

Rabinowitsch Equation

An equation that relates the flow rate of non-Newtonian fluids in a cylindrical tube, accounting for shear stress.

Newtonian Fluid

A fluid with a constant viscosity regardless of the shear rate, following Newton's law of viscosity.

Blood Is Non-Newtonian

Indicates that blood does not maintain a constant viscosity and its flow characteristics depend on shear rate.

Apparent Viscosity (𝜇)

The effective viscosity of a non-Newtonian fluid; can change depending on the shear rate and conditions.