Dear all,

I am now confusing about the fundamental concepts of turbulence.

What's fully developed turbulence? Surely we could see the Re is high enough, but we don't know the exact value for the word "high" for a given complex flow. There should exist some criteria to determine the flow state. I have found some one use turbulent energy spectrum to judge whether it is fully developed turbulence or not based on -5/3. I don't know whether this is a general method.

Any comment is welcome, if possible please give the references. thanks a lot!

regards, sincerely, sarah

Hi, I think that the fully developed turbulence is in the exterior region for turbulent boundary layer where the wall laws are not valid and the effects of fluid viscoity are negeligeables.