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Old   April 26, 2011, 09:07
Default source on surface.
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Rafał Kryjak
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I have HTC on surface and I'd like to add source on it. i.e. function of heat flux. I choose Sources -> Boundary Source -> Sources -> Energy -> Flux and it doesn't work.

Has anybody got suggestions what's going on ?

Last edited by dzuodoka; May 3, 2011 at 14:15.
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Old   April 26, 2011, 21:52
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What does not work about it?
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Old   April 27, 2011, 02:56
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The heat flux doesn't appear in postprocessor. It seems to be not choosen in pre but it is like I explained.

Last edited by dzuodoka; April 27, 2011 at 12:17.
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Old   April 27, 2011, 19:24
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What do you mean "The heat flux doesn't appear in post"? I am not sure about this but your heat flux will not appear in the "Wall Heat Flux" variable. If you want to see how much heat you are applying you have to use an additional variable to output it to the post processor - this is a good idea in development of source terms so you can check the source term is correctly applied.
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Old   May 3, 2011, 14:54
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Rafał Kryjak
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Thanks a lot for your response.

I still have problem with seeing my heat flux source in the post-procesor. Could you write it down more clearly.

Maybe I should put it this way. I have external wall with HTC condition and I would like to ask how to add heat flux source on it ?
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Old   May 3, 2011, 19:16
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Quote:
I have external wall with HTC condition and I would like to ask how to add heat flux source on it ?
You should be able to put a source term on the face in CFX-Pre in the boundary tab. Simple.
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Old   May 21, 2011, 07:10
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Rafał Kryjak
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I found out where was the problem. That is, if you add Heat Flux as a boundary condition you get fixed value of heat flux on a surface, but if you add Heat Flux extra to HTC condition as a source you get value changed by heat transfer.

Do you think in that way adding heat flux as a source is appropriate and results will be physically accepted ? I think it is but I'd like to get to know your opinions. Thanks a lot.
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Old   May 21, 2011, 07:58
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You set the boundary up to match reality. If HTC is closest then use that. If it is being heated by some external heating use a heat flux. If it has both convection and external heating use convection and a heat flux source term.
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Old   May 30, 2011, 04:08
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Quote:
Originally Posted by ghorrocks View Post
....... If you want to see how much heat you are applying you have to use an additional variable to output it to the post processor - this is a good idea in development of source terms so you can check the source term is correctly applied.

Could you explain it more clearly because I don't get it how to aplly this additional variable to see my heat flux source ?

The post processor shows only het flux q=HTC*deltaT and it is clear but I want to display also heat flux source q_source in the post processor.
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Old   May 30, 2011, 06:21
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Define a CEL expression as you heat source, then define an additional variable linked to that heat source. Your heat source will now appear int he post procesor under the additional variable.
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