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BoussinesqApproximation for incompressible flow

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Old   August 19, 2008, 07:45
Default Hi Fabian, Thank you for at
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Masashi IMANO
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Hi Fabian,

Thank you for attaching your code again.

As a matter of fact I have made fixed heat flux B.C. library like you have made,
but I intentionally remove heat flux B.C from the airConditionedRoom tutorial case
in order to decrease installation process like compiling addtional custom library.

However the fixed flux B.C. is more general and elegant in this tutorial indeed,
so I wrote a Wiki page of my fixed heat flux B.C. library and added an
option to use heat flux B.C. into airConditionedRoom tutorial case.

http://openfoamwiki.net/index.php/Contrib_wallHeatFlux
http://openfoamwiki.net/index.php/Ma...onditionedRoom

Please have a look at Wiki pages and source code for detail.

The Last question about the wall function:
The separate treatment for temperature might be needed indeed,
but currently I have no plan to implement them soon...
So I wish someone get started on them...

Masashi
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Old   August 19, 2008, 13:24
Default Nice :-) Do you have a hint, a
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Fabian Braennstroem
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Nice :-) Do you have a hint, about implementing it?
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Old   August 19, 2008, 13:24
Default ... I mean the wall treatment.
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Fabian Braennstroem
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... I mean the wall treatment.
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Old   November 4, 2008, 07:12
Default In the code by Masashi, the wa
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Christian Lindbäck
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In the code by Masashi, the wall heat transfer is calculated as:
temperature gradient = q/(alpha_eff*Cp0*rho0)

Cp will not vary much with temperature, but density will change more than negligable for my case. What do you think, wouldn't it be better to express rho in terms of rho0, beta, g, T and T0 (Boussinesq approximation)?

Hope to have someones opinion.

Regards,
Christian Lindbäck
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Old   November 17, 2008, 04:56
Default Hi to all What is beta here
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emilianyassenov
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Hi to all

What is beta here?

can anyone tell me?

Emo
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Old   November 17, 2008, 05:35
Default Beta is the thermal expansion
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Se-min JEONG
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Beta is the thermal expansion coefficient.

http://web.njit.edu/topics/Prog_Lang_Docs/html/FLUENT/fluent/fluent5/ug/html/nod e296.htm
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Old   November 17, 2008, 06:11
Default Hi Jeong Thanks for the qui
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emilianyassenov
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Hi Jeong

Thanks for the quick answer...
but i could not open your site...is it without dimension or?

thanks in advance!!
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Old   November 17, 2008, 08:26
Default Dear Emilian, The dimensio
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Se-min JEONG
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Dear Emilian,

The dimension is [1/K].

You can check its dimension and value in the "/constant/transportProperties" file of the example directory.

http://www.engineeringtoolbox.com/ai...ies-d_156.html
http://en.wikipedia.org/wiki/Coeffic...rmal_expansion

Jeong
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Old   November 28, 2008, 04:59
Default Dear Hrvoje, is the Boussin
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scurtu
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Dear Hrvoje,

is the Boussinesq approximation solver
/OpenFOAM-1.4.1-dev/applications/solvers/heatTransfer/boussinesqBuoyantFoam/
compatible with OpenFOAM-1.5?
If not what modifications it request?

Nicoleta
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Old   November 28, 2008, 06:38
Default I think it will work with no c
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Hrvoje Jasak
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I think it will work with no changes - try to compile and see what happens.

There sound le no problems.

Enjoy.

Hrv
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Old   May 13, 2009, 05:20
Default boussinesq approximation
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Bintoro Aji
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Hi,
I am new to OpenFoam. I'd like to solve the problem of natural convection heat transfer in rod bundle that generating 200 kW of power. Is the boussinesq approximation solver enough for this case, since there will be two phase flow when boiling happen?

bintoro
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Old   July 15, 2009, 03:54
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Praveen
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hello Masashi,

I am trying to solve solidification problem and have written a code. Im using the wallHeatFlux BC for cooling the walls of the mould provided by you on the wiki page.

When the liquid starts to solidify, i see that the temperature at the walls become lower and goes negative. could u give any suggestions about how to overcome this problem.
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