In my opinion, CFD is a very vast and interesting subject and tool but the one thing which seems to be very enigmatic is turbulence modelling.
My question here is quite simple:
1) How would you explain turbulence and turbulence modelling to a kid?
2) Why do we have so many turbulence models and why is it so hard to model turbulence accurately?
3) From an aerospace perspective, does anyone have ideas of How turbulence works in Hypersonics? Or do we even have turbulence there?
Would love to see some interesting answers on the same!