The Krogh Length, λ K {\displaystyle \lambda _{K}} , is the distance to which nutrients diffuse between capillaries, based on cellular consumption of the nutrients. It can be described as:
λ K = D s c o / R {\displaystyle \lambda _{K}={\sqrt {D_{s}c_{o}/R}}}
where D s {\displaystyle D_{s}} is the diffusion constant of the solute in the substrate, c o {\displaystyle c_{o}} is the concentration in the channel, and R {\displaystyle R} is the consumption by the cells. Units are in terms of length.
See also August Krogh Biomedical engineering Capillaries Diffusion Biot number Peclet number
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