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September 29th, 2018, 05:49 AM   #1
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pancakes

This morning I made some pancakes out of that pre-mix stuff that you add water to and shake. I forgot to shake the mix before adding water so the final product wasn't entirely homogeneous (to my disappointment).

Anyway, after heating them on a dead flat non-stick fry pan, I observed that some of the pancakes had very distinct but imperfect honey-comb shaped patterns on one side. What on earth would cause such a thing? The only time I've seen anything even remotely similar is when vibrations are applied to a rectangular membrane with sand on top.

I suppose the unmixed parts of the pancakes would have 'sunk' to the bottom of the pancake faster, heated up and formed ridges, but how this shape I don't know...
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September 29th, 2018, 06:57 AM   #2
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Was the pan initially very hot? If so, were the affected pancakes cooked on the hottest parts of the pan?
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September 29th, 2018, 08:52 AM   #3
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This is cool. I know that hexagon patterns often emerge in steady state solutions for some nonlinear PDEs. For example, I know it happens in Rayleigh-Benard convection and the Swift-Hohenberg equations.

However, I don't have a single clue what those patterns mean or why they appear. I'd be interested if anyone has a good explanation or link.
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September 29th, 2018, 09:09 AM   #4
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This is cool.
Noooooo it's not; Joppy told us:
"Anyway, after heating them on a dead flat non-stick fry pan..."
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September 29th, 2018, 03:11 PM   #5
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Originally Posted by skipjack View Post
Was the pan initially very hot? If so, were the affected pancakes cooked on the hottest parts of the pan?
I wouldn't say very hot. Just enough to melt butter. And yes, the affected sides were those which went in first, being placed at the center of the pan (the hottest part I assume).

Quote:
Originally Posted by SDK View Post
This is cool. I know that hexagon patterns often emerge in steady state solutions for some nonlinear PDEs. For example, I know it happens in Rayleigh-Benard convection and the Swift-Hohenberg equations.

However, I don't have a single clue what those patterns mean or why they appear. I'd be interested if anyone has a good explanation or link.
Are you saying they might be convection cells? I can't find any examples of these in viscous liquids though, which I think would resemble the pancake situation better.
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September 29th, 2018, 03:37 PM   #6
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Just enough to melt butter. And yes, the affected sides were those which went in first, being placed at the center of the pan
Sounds like the oil bubbling. I get it on better mixed pancakes, but only the first after refreshing the oil.
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September 29th, 2018, 04:29 PM   #7
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Quote:
Originally Posted by Joppy View Post
I wouldn't say very hot. Just enough to melt butter. And yes, the affected sides were those which went in first, being placed at the center of the pan (the hottest part I assume).


Are you saying they might be convection cells? I can't find any examples of these in viscous liquids though, which I think would resemble the pancake situation better.
No I'm not talking about the convection cells themselves. The hexagon patterns form inside and "tile" a single convective cell in the models I mentioned.
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September 29th, 2018, 04:50 PM   #8
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Quote:
Originally Posted by v8archie View Post
Sounds like the oil bubbling. I get it on better mixed pancakes, but only the first after refreshing the oil.
Yes that probably adds to it. Though it can happen without re-buttering/oiling.

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Originally Posted by SDK View Post
No I'm not talking about the convection cells themselves. The hexagon patterns form inside and "tile" a single convective cell in the models I mentioned.
This is quite similar to what I see. There is a somewhat related discussion about the shape of cracked desert topsoil here.

I can't find examples of polygonal shapes forming inside the cells. It seems the cells are either unstructured 'blobs' or they form polygonal shapes.

What a complicated breakfast!
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September 29th, 2018, 07:05 PM   #9
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Did you get an indigestion?
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September 29th, 2018, 07:17 PM   #10
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Did you get an indigestion?
An indigestion? I don't get it.

But yes I felt like I was chewing on a rubber tire.
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