# How to estimate the Kolmogorov length scale

My understanding of Kolmogorov scales doesn't really go beyond this poem:

Big whirls have little whirls that feed on their velocity, and little whirls have lesser whirls and so on to viscosity. - Lewis Fry Richardson

Th smallest whirl according to Wikipedia would be that big:

$\eta = (\frac{\nu^3}{\varepsilon})^\frac{1}{4}$

... with $\nu$ beeing kinematic viscosity and $\epsilon$ the rate of energy disspiation.

Since I find no straightforward way to calculate $\epsilon$, I'm completely at loss at what orders of magnitude to expect. Since I imagine this to be an important factor in some technical or biological processes, I assume that someone measured or calculated these microscales for real life flow regimes. Can anyone point me to these numbers?

I'm mostly interested in non-compressible fluids, but will take anything I get. Processes where I believe the microscales to be relevant are communities of synthropic bacteria (different species needing each others metabolism and thus close neighborhood) or dispersing something in a mixture.

From the quotes poem, you can anticipate that everything that is dissipated at the smallest scales, has to be present at larger scale first. Therefor, as a very crude estimate, for a system of length $L$ and size $U$ (and dimensional grounds, on this scale viscosity does not play a role!), one could argue that
$$\varepsilon=\frac{U^3}{L}$$
For the crude estimate, one could use this $\varepsilon$ to estimate the Kolmogorov length scale.
To put in numbers, suppose you ($L=1m$) are running ($U=3m/s$) (in air $\nu=1.5\times10^{-5} m^2/s$), then, $\eta=100\mu m$. Which sounds at least reasonable.