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thermal boundary option

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Old   February 27, 2010, 06:12
Default thermal boundary option
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liang liam
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hello everyone~
I have a problem about ...heat transfer coefficients that is from
model setup/boundaries/mesh boundaries/mesh block/wall/thermal information/thermal boundary options

there are heat transfer coefficient to fluid 1 &to fluid 2 ,does anybody know that means?
thanks
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Old   February 28, 2010, 20:52
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michael barkhudarov
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if the mesh boundary is of type 'wall' with a specified temperature, then it needs an htc between the wall and adjacent fluid to compute the heat flux at the boundary. The user can defined a different htc for fluid 1 and 2 in two-fluid problems.

does it make sense?
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Old   March 1, 2010, 00:55
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Michael
i thought the heat transfer coefficient is calculated by the solver while solving the conjugate heat transfer problem? pls help to clarify.
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Old   March 1, 2010, 12:23
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michael barkhudarov
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Yes, the solver will do it if you leave these input entries blank.
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Old   March 3, 2010, 11:07
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liang liam
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Quote:
Originally Posted by MuxaB View Post
if the mesh boundary is of type 'wall' with a specified temperature, then it needs an htc between the wall and adjacent fluid to compute the heat flux at the boundary. The user can defined a different htc for fluid 1 and 2 in two-fluid problems.

does it make sense?
but if I set the 'wall' as copper that have thermal conductivity value(k),does it needs a htc ?
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Old   March 3, 2010, 19:27
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michael barkhudarov
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It does not really matter what material it is made of. The user can either define a constant htc at the fluid/wall interface, or the code will compute it automatically as a function of the materials properties and the flow. In the latter case, it assumes that the contact between copper and fluid is perfect, i.e., no thermal resistance.
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