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Blood viscosity is a measure of the resistance of blood to flow. It can also be described as the thickness and stickiness of blood. This biophysical property makes it a critical determinant of friction against the vessel walls, the rate of venous return, the work required for the heart to pump blood, and how much oxygen is transported to tissues and organs.
Consequently, if a liquid has dynamic viscosity of n centiPoise, and its density is not too different from that of water, then its kinematic viscosity is around n centiStokes. For gas, the dynamic viscosity is usually in the range of 10 to 20 microPascal-seconds, or 0.01 to 0.02 centiPoise. The density is usually on the order of 0.5 to 5 kg/m^3.
Erythrocyte deformability is an important determinant of blood viscosity, hence blood flow resistance in the vascular system. [3] It affects blood flow in large blood vessels, due to the increased frictional resistance between fluid laminae under laminar flow conditions.
η(δ) = viscosity of blood in the wall plasma release-cell layering; r = radius of the blood vessel; δ = distance in the plasma release-cell layer; Blood resistance varies depending on blood viscosity and its plugged flow (or sheath flow since they are complementary across the vessel section) size as well, and on the size of the vessels.
In physics and chemistry, a non-Newtonian fluid is a fluid that does not follow Newton's law of viscosity, that is, it has variable viscosity dependent on stress. In particular, the viscosity of non-Newtonian fluids can change when subjected to force. Ketchup, for example, becomes runnier when shaken and is thus a non-Newtonian fluid.
The Fåhræus–Lindqvist effect (/ f ɑː ˈ r eɪ. ə s ˈ l ɪ n d k v ɪ s t /) or sigma effect [1] describes how the viscosity of blood changes with the diameter of the vessel it travels through. In particular there is a decrease in viscosity as the vessel diameter decreases, but only at small diameters of 10–300 micrometers (mainly ...
Although elevated whole blood viscosity is a better measure of hyperviscosity and more common and clinically important, serum viscosity and plasma viscosity are more frequently measured. [3] Normal plasma viscosity is between 1.4 and 1.8 centipoise while symptoms from hyperviscosity typically occur greater than 4 centipoise (about 4 times more ...
Under standard atmospheric conditions (25 °C and pressure of 1 bar), the dynamic viscosity of air is 18.5 μPa·s, roughly 50 times smaller than the viscosity of water at the same temperature. Except at very high pressure, the viscosity of air depends mostly on the temperature.