It's a blog! Mainly of book reviews.
If I read "...a characteristic scale length, l," without any explanation of how to determine such a length in any specific case one more time, I am liable to scream. This isn't an isolated problem; undefined terms are popping up all over the place. The author also appears to have missed a subtle point about vorticity in fluid flows, namely it totals to zero even in a turbulent flow, unless there is external stirring.