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Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by semi-extrinsic on Saturday November 26, 2016 @12:19PM (#13044693)
It's all down to the Reynolds number, which relates viscosity ('sluggishness' of the fluid) n, length scale L and speed v. Re = v*L/n; if this number is low, stuff "happens slowly", if large, stuff "happens quickly".

So if you scale things up, making L larger, you can get fluids that we usually think of as "slow" to act like they're "quick". Like magma: very sticky, but a big enough lava flow can outrun a car.

<insert standard disclaimer about handwaving in above comment>

Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by semi-extrinsic on Saturday November 26, 2016 @12:57PM (#13044948)
Also, as someone in fluid dynamics, I find it interesting that this student project is featured in the NY Times. I mean, it's not trivial, but it's certainly less work and less interesting/innovative than e.g. what the average PhD student produces.

Would it have been in the NY Times if someone at a less prestigious university, led by a less well-connected advisor, had given this project? Somehow I doubt it.

Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by davidf18 on Saturday November 26, 2016 @01:53PM (#13045270)
It paints a bizarre picture of people running from and being killed by waves of gooey, molten sugar, hence a story of interest to the general public, yet one based in science and engineering.
Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by bcaulfield on Tuesday November 29, 2016 @07:09PM (#13067358)
There's an old saying in journalism "if it bleeds it leads." Holds true even in science coverage, and even at the New York Times.
Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by csours on Saturday November 26, 2016 @01:40PM (#13045197)
Its also a popular culture reference. Some grad student somewhere is making a discovery about paint that will eventually make Behr a lot of money, but we won't hear about it until the commercials, and maybe not even then.
Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by aaron695 on Sunday November 27, 2016 @03:25AM (#13048302)
> but it's certainly less work and less interesting/innovative than e.g. what the average PhD student produces.

It kinda sounds like you think work alone should be rewarded rather than outcome?

If PHD students create useless reports after a lot of work then that's their issue. Creating busywork to justify a PHD seems a flawed process.

If PHD students create scientifically great reports then that has no place in the NYT, it's place is in scientific magazines.

If no one has modeled this before (very surprising if true) then this is very interesting news, and pretty good science to boot.

Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by daveguy on Saturday November 26, 2016 @12:55PM (#13044941)
I wonder how large the pitch drop experiment would have to be before it produced continuous visible flow at room temperature.

https://en.m.wikipedia.org/wiki/Pitch_drop_experiment

Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by semi-extrinsic on Saturday November 26, 2016 @03:41PM (#13045727)
To clarify the question: do you mean that the flow is such that you can clearly see motion, or that the stream of pitch flowing down does not break up into droplets? (The latter depends also on surface tension, the former does not.)
Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by daveguy on Saturday November 26, 2016 @07:57PM (#13047048)
I was thinking such that there is sufficient flow to see motion (say 1 mL/min). I think the boundary between droplets vs continuous flow is a more difficult problem.
Re:Solving a Mystery Behind the Deadly ‘Tsunami of Molasses’... by semi-extrinsic on Saturday November 26, 2016 @03:37PM (#13045718)
Interesting question. It depends of course on the combination of how restrictive the nozzle is (as compared to the width of the column above), and the height of the pitch above the nozzle. If you take the geometry of the pitch drop experiment as fixed, varying only the radius (of both nozzle and column), keeping the pitch height constant, I believe that problem can be solved. Will think about it.