Capillaries blood flow velocity through

The velocity of blood flow through capillaries is slow compared to the rest of the circulatory system because of the very large total cross-sectional surface area of the capillaries. Although each individual capillary has a diameter of... 

The flow rate of blood through the heart is approximately 4-5lmin for adults. The typical mean blood velocity through the aorta (which is the largest artery with a diameter of 2-3 cm), when pumped from the left heart, is approximately 25 cm s"i (mean) the maximum velocity is approximately 60 cm s h The Reynolds number for the maximum velocity is about 3000. In general, the blood flow through arteries and veins is laminar in nature. In capillaries, the typical blood velocity is 0.5-1 mm s , and the Reynolds number is on the order of 0.001. 

If magnitude and/or direction of velocity vary on a length scale below spatial resolution, the detected motion is incoherent. (Self-) diffusion certainly falls into this category, but randomly oriented flow is also spatially incoherent. A well known example is the blood flow through brain capillaries, which are smaller than a voxel... 

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