Asymptotic (invariance) assumption in turbulence

vasanth

Hello,

I am a beginner in turbulence.I have been going through some basic stuff on turbulence and did not understand a couple of things.

1)The asymptotic assumption says that as Reynolds number tends to infinity the shear flow becomes independent of most of its environment,except for boundary conditions imposed by the overall flow. What is the meaning or significance of flow getting independent of its enverionment?

2)The small scale eddies have very short time scales,which tend to make them statistically independent of the mean flow.I did not understand this statement at all.What is statistically independent?

Thanks in advance Vasanth