heat equation

Numerical methods and mathematical models of Elmer
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kevinarden
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heat equation

Post by kevinarden »

Is there a symmetry boundary for the heat equation? If so how do you set it?
mzenker
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Re: heat equation

Post by mzenker »

Hi,

I don't know what you want to do exactly...?
Maybe chapter 9 of the Solver Manual is interesting for you.

Matthias
kevinarden
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Re: heat equation

Post by kevinarden »

Modeling conduction through a frying pan, but only modeled half of it. I think the symmetry boundary should have no heat flow through it.
pan.png
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kevinarden
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Re: heat equation

Post by kevinarden »

TIme 0 and TIme 49
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[attachment=0]time49.png[/attachment
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mzenker
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Re: heat equation

Post by mzenker »

When I look at the pictures, I don't see an obvious problem. Do you? I may be missing something, of course... ;)
Normally I would just not set any BC at the symmetry border. Since there is nothing behind it, there is nothing which can exchange heat with the half pan.

Matthias
kevinarden
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Re: heat equation

Post by kevinarden »

I believe you are correct, the default is no transfer or radiation, one would have to be defined.
raback
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Re: heat equation

Post by raback »

Hi

For Poisson equations (Heat equation is one) the natural BC is also the symmetry BC. So no need to do anything and you get zero normal flux.

-Peter
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