Due to lack of understanding of precise underlying mechanisms, turbulent flow in liquids, gases and powders (etc) cannot be exactly predicted.
There is as yet no theorem relating Reynolds Number to turbulence.
Quote from: Prof. Richard Feynman - “Turbulence is the most important unsolved problem of classical physics.” (Feynman R., Leighton R. B., Sands M. (1964) The Feynman lectures on physics)
Quote from: Sir Horace Lamb - “I am an old man now, and when I die and go to heaven there are two matters on which I hope for enlightenment. One is quantum electrodynamics, and the other is the turbulent motion of fluids. And about the former I am rather optimistic.” (in a speech to the British Association for the Advancement of Science in 1932)
Source: Transactions of the Royal Society A
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