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Thermal boundaray conditions

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Old   July 27, 2019, 17:04
Question Thermal boundaray conditions
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Edwin P
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Hello,


I have a long duct opened at atmospheric pressure. I want to model a small section near to the end of the duct which generates heat. I have transient measurements of temperature at the beginning and at the end of the that section. At time t=0, all the system is at ambient temperature.


Should I use both the inlet and oultlet temperature measurements of my sections as a boundary conditions in Ansys Fluent?


Help me please,


Regards
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Last edited by intied; July 27, 2019 at 17:05. Reason: typo error
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Old   July 29, 2019, 01:48
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Alexander
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from my point of view it depends on the goal of your simulation.

Make a decision -> what you want to simulate, then put boundary conditions

best regards
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Old   July 29, 2019, 02:52
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Svetlana Tkachenko
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Why is the temperature transient? Is this an externally imposed boundary condition in the experiment?
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Old   July 29, 2019, 11:53
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Quote:
Originally Posted by Светлана View Post
Why is the temperature transient? Is this an externally imposed boundary condition in the experiment?

The temperature increase inside the duct is due to a solid with internal heat generation. I added a source term and I want to model its transient temperature profile
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Old   July 29, 2019, 13:01
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You can't impose an outlet temperature, not that you would need to, anyway. You would just use pressure outlet or outflow BC or something.


Just make sure you have the right inlet conditions and whatever else you need for your simulation. I can't follow what you want to do with heat generation and an inlet temperature.
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Old   July 29, 2019, 16:18
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Quote:
Originally Posted by LuckyTran View Post
You can't impose an outlet temperature, not that you would need to, anyway. You would just use pressure outlet or outflow BC or something.


Just make sure you have the right inlet conditions and whatever else you need for your simulation. I can't follow what you want to do with heat generation and an inlet temperature.

Thank you.



In fact, I am using pressure inlet and pressure outlet as boundary conditions. But, I am not sure if I have to use the transient temperature profile in the "Thermal" tab of those boundary conditions.



By other hand, I have a small solid which generates heat. I want to model its transient temperature.
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Old   July 29, 2019, 19:25
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Originally Posted by Светлана View Post
Why is the temperature transient? Is this an externally imposed boundary condition in the experiment?

I have a small solid which generates heat due to joule effect. Therefore, near to that soild, the ambient temperature changes.


Thank you
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