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-   -   Heat transfer coefficient for porous domain (http://www.cfd-online.com/Forums/cfx/108843-heat-transfer-coefficient-porous-domain.html)

l.te November 2, 2012 11:18

Heat transfer coefficient for porous domain
 
Hi dears,
anyone can tell me how to calculate the heat transfer coefficient for a porous domain with a solid continous component (fiberglasses) and a fluid continous component (resin)?
I know that this coefficient varies with the temperature, so I want to do an expression for it, but how to do it?.
I read the help but I didn't find my case!
P.S. I know the interfacial area density of the porous.

singer1812 November 2, 2012 12:00

Perhaps

h=q/(Twall-Tref)

You choose the Tref yourself.

l.te November 2, 2012 12:55

Quote:

Originally Posted by singer1812 (Post 389913)
Perhaps

h=q/(Twall-Tref)

You choose the Tref yourself.

Hi singer1812, the problem is that my cylindrical porous domain is heated at the wall by an imposed thermal profile (given through an expression "Twall"), so I don't know "q" a priori.
Besides, also T of the resin varies along the profile of the part.

singer1812 November 2, 2012 12:59

areaAve(Wall Heat Flux)@your area

or if you dont want area averaged h, then create a variable for h using

Wall Heat Flux

And what ever Tref you want.

l.te November 2, 2012 15:00

Quote:

Originally Posted by singer1812 (Post 389925)
areaAve(Wall Heat Flux)@your area

or if you dont want area averaged h, then create a variable for h using

Wall Heat Flux

And what ever Tref you want.

Hello, areaAve is a post-processor command, I need to have heat transfer coefficient in pre-processor, to insert it in the porous domain tab.
And this heat transfer coeffcient is between solid an fluid part inside the porous domain, so I don't have an area as boundary location between the two phases.

singer1812 November 2, 2012 15:19

Ahh, I misunderstood. I thought you wanted to pull out an h off of your solution.

You are looking for an emperically based h. I am not totally familar with fluid-solid h correlations for porous medium, and they will be quite specific to certain applications.

l.te November 3, 2012 11:14

Quote:

Originally Posted by singer1812 (Post 389957)
Ahh, I misunderstood. I thought you wanted to pull out an h off of your solution.

You are looking for an emperically based h. I am not totally familar with fluid-solid h correlations for porous medium, and they will be quite specific to certain applications.

thanks anyway singer1812

hmasenger June 20, 2014 03:05

hi i.te
did you find any answer for your problem? i think i have same trouble with variable h.any clue would really help


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