

To Predict Turbulence, Just Count the Puffs (2014) - dnetesn
http://nautil.us/issue/25/water/to-predict-turbulence-just-count-the-puffs-rp

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anon4327733
Turbulence seems to be very weird. This article talks about the birth and
death rate of puffs. In a modified version of the Navier-Stokes equation
Terrence Tao was able to construct logic gates and use those to create a self
replicating eddy.

[https://www.quantamagazine.org/20140224-a-fluid-new-path-
in-...](https://www.quantamagazine.org/20140224-a-fluid-new-path-in-grand-
math-challenge/)

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JadeNB
> Turbulence seems to be very weird.

Right up there with "the Riemann hypothesis is quite difficult." (Of course,
probably nothing beats the irony in naming of the Fundamental Lemma
([https://en.wikipedia.org/wiki/Fundamental_lemma_%28Langlands...](https://en.wikipedia.org/wiki/Fundamental_lemma_%28Langlands_program%29)).)

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Vexs
I love nautilus because it can make the most seemingly inane things incredibly
interesting. I've never thought about turbulence at all; or even guessed it
would be difficult to figure out the cause but this, for lack of a better
term, opened my eyes.

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semi-extrinsic
Feynman described turbulence as "the most important unsolved problem of
classical physics."

Another quote, attributed both to Heisenberg and to Horace Lamb: "When I meet
God, I am going to ask him two questions: Why relativity? And why turbulence?
I really believe he will have an answer for the first."

And the very related problem of the existence and smoothness of solutions to
the Navier-Stokes equations is one of the famous millennium problems.

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stefanomazzalai
Unless you have access to a DOE-grade supercomputer :) good interview here w/
one of the pioneers of Large Eddy Simulation for turbulence physics:

[http://www.cascadetechnologies.com/pioneering-large-eddy-
sim...](http://www.cascadetechnologies.com/pioneering-large-eddy-simulation-
an-afternoon-with-prof-parviz-moin-part-i/)

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semi-extrinsic
LES is an approximation, and there are cruder (RANS) and finer (DNS) ones
available. And while these are very cool and useful e.g. for studying how
turbulence affects other things (structures, particle in suspension etc.) they
don't tell us much about turbulence itself.

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qCOVET
I am always intrigued by the topic of turbulence and its implications in
weather prediction. One of the key challenges of weather prediction is our
inability to understand / predict atmospheric turbulence...most importantly
'chaotic turbulences'.

Details (European Research Council): [http://erc.europa.eu/succes-
stories/understanding-turbulence...](http://erc.europa.eu/succes-
stories/understanding-turbulence-key-weather-prediction)

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finnh
I love the examples of turbulence and laminar flow in Fantastic Mr Fox - hard
to find on youtube but this clip[0] has about 3 seconds of what I'm talking
about

[0]
[https://www.youtube.com/watch?v=7vjMc_HlNic](https://www.youtube.com/watch?v=7vjMc_HlNic)
@ 1:22-1:24

