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Old   January 22, 2012, 12:30
Question Please Help me!!!!
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hi,
I have a big problem.

I have a cubic that have three prependicular solid pipes in it and them are related to the suroundings that have the temperature of 320K except pipes in inlet and outlet. I create the mesh file in Gambit.
due to pipes temerature my fluid heated. fluid comes in at 0.1m/s and 300K and exit from opposite face.

I want to find the temperature of end of pipes but in exit face I don't know what BC shoud I make.

fluent automatically seperate the pipes into a wall and four circle that made from intersecting by the cubic face. I dont know what BC should I make.

please guide me!

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Old   January 22, 2012, 13:15
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Sijal Ahmed Memon (turboenginner@gmail.com)
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Quote:
fluent automatically seperate the pipes into a wall and four circle that made from intersecting by the cubic face. I dont know what BC should I make.
What type of boundary conditions you want to specify? and where?
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Old   January 23, 2012, 04:12
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Quote:
Originally Posted by Far View Post
What type of boundary conditions you want to specify? and where?
hi,
in enterance T=300K and velocity is 0.1m/s

in walls we have T=320K that cause the pipes heated

Exit face is just an outlet that the ambient temperature is 300K.

problem is in the automatically seperation of walls. Fluent consider the intersection of pipe and surroundings as a wall!!!

what can I do?
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Old   January 23, 2012, 14:21
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Quote:
Originally Posted by adambarfi View Post
hi,
in enterance T=300K and velocity is 0.1m/s

in walls we have T=320K that cause the pipes heated

Exit face is just an outlet that the ambient temperature is 300K.

problem is in the automatically seperation of walls. Fluent consider the intersection of pipe and surroundings as a wall!!!

what can I do?

Please check your mesh in Gambit. You have the wall imposed on the outlet of the pipe.
If that is the case you may have to subtract the volume of the pipes from the volume of the container in which you have the pipes.
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Old   January 23, 2012, 17:50
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Check that all volumes have mesh
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Old   January 26, 2012, 03:00
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hi,
I cheched it agian, that was allright.

I could solve the problem, I assume that at inlet and out let we have first fluid that Enter to the body and exit from it. this was responsed.

but still I have a problem

I want my pipes that related to the walls have the same temperature with walls. my surrounding walls the temperature of 320K that due to the fluid flow it changes. I want the intersection of pipes and walls that fluent assume it as a wall have tempereture same the walls.

here is anyone can help me?

thanks
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