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Definitions in the Heat Transfert interface

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Hi,

We are using the Heat Transfert interface in solids for a PEMFC model. In this interface we have added a "Heat Source" module. In this one we can choose the following expressions :

- Total power dissipation density (siec/per1)
- Total power dissipation density (siec/ice1)

We know that it is based on the Second Current Distribution interface but we don't know the difference between them.

Could anybody help us ?

Thank you very much.

CARNIATO Pierre
CHEMIN Julien

2 Replies Last Post 2011年1月21日 GMT-5 10:15
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2011年1月21日 GMT-5 09:18
Hi

I believe you can turn on the "Equations" in the "Preferences", and then search for the variables and look what it says there.

Then you can do an indexed search on the help doc files, and most propably you will find further explanations, maybe dilluted in several volumes, but still there, in words.

make it a try ;)

--
Good luck
Ivar
Hi I believe you can turn on the "Equations" in the "Preferences", and then search for the variables and look what it says there. Then you can do an indexed search on the help doc files, and most propably you will find further explanations, maybe dilluted in several volumes, but still there, in words. make it a try ;) -- Good luck Ivar

Magnus Ringh COMSOL Employee

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Posted: 1 decade ago 2011年1月21日 GMT-5 10:15
Hi,

These are two contributing heat sources due to electromagnetic power dissipation. They appear as predefined heat source expressions. The names in parentheses, such as (siec/per1), show where in the Secondary Current Distribution interface these sources appear:

- siec is the (default) interface identifier for the Secondary Current Distribution interface.
- per1 is the (default) tag for the Porous Electrode Reaction 1 node (a subnode to a Porous Electrode node). If you check the variables list in the Equation View for this node, you can see the definition of this power dissipation density, siec.Qh.
- ice1 is the (default) tag for the Electrolyte 1 node. If you check the variables list in the Equation View for this node, you can see the definition of this power dissipation density. The variable name is the same, siec.Qh.

The porous electrode and the electrolyte appear in different domains in a model and can each contribute with a heat source in their respective domains.

The tags appear within curly braces in the model tree if you select "Show Name and Tag" from the View menu (the small downward triangle in the upper-right corner of the Model Builder window). From the same menu, select Show Equation View if you want to inspect the defintions of variables and equations in the Equation View nodes.

Best regards,
Magnus Ringh, COMSOL
Hi, These are two contributing heat sources due to electromagnetic power dissipation. They appear as predefined heat source expressions. The names in parentheses, such as (siec/per1), show where in the Secondary Current Distribution interface these sources appear: - siec is the (default) interface identifier for the Secondary Current Distribution interface. - per1 is the (default) tag for the Porous Electrode Reaction 1 node (a subnode to a Porous Electrode node). If you check the variables list in the Equation View for this node, you can see the definition of this power dissipation density, siec.Qh. - ice1 is the (default) tag for the Electrolyte 1 node. If you check the variables list in the Equation View for this node, you can see the definition of this power dissipation density. The variable name is the same, siec.Qh. The porous electrode and the electrolyte appear in different domains in a model and can each contribute with a heat source in their respective domains. The tags appear within curly braces in the model tree if you select "Show Name and Tag" from the View menu (the small downward triangle in the upper-right corner of the Model Builder window). From the same menu, select Show Equation View if you want to inspect the defintions of variables and equations in the Equation View nodes. Best regards, Magnus Ringh, COMSOL

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