Capillary diameter

The diameter of the capillary is required to calculate the pressure flow coefficient of the capillary.

$K_{k} = \frac{π \cdot d_{k}}{128 \cdot η_{0} \cdot l_{k}}$

K_k	pressure flow coefficient of the capillary
l_k	length of the capillary
d_k	diameter of the capillary