Eddy turnover time
= Eddy turnover time
{title2=$\tau_l\sim l/\delta u_l$}
The eddy turnover time estimates how long a velocity difference $\delta u_l$ takes to distort a structure of size $l$. In a local strong <energy cascade>, the transfer time is assumed comparable to it. A <weak wave cascade> can transfer energy much more slowly because a single encounter makes only a small fractional change.