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-   -   OpenFOAM solver for incompressible BUT temperature dependent flow (https://www.cfd-online.com/Forums/openfoam-solving/160415-openfoam-solver-incompressible-but-temperature-dependent-flow.html)

niko0807 October 7, 2015 11:57

OpenFOAM solver for incompressible BUT temperature dependent flow
 
Hello,

I am modeling heat transfer in a tube bank heat exchanger - primarily from surface to air. The temperature differences are as large as 180 K throughout the domain.

I have investegated the possibility of solving the flow as incompressible with buoyantBoussinesqPimpleFoam but concluded that variations in nu (about 50 %) are to big to assume constant viscosity.

Velocities are low and the static pressure variation negligible. Therefore, I am keen on knowing whether there is a thermal incompressible solver where the viscosity can be made temperature dependent (with polynomials for example).

Does anyone know about a thermal incompressible solver where viscosity can be made temperature dependent?

tas38 October 7, 2015 14:34

You can write your own solver to account for temperature variation of viscosity,
for example. See the link below for a report that may provide some useful
guidance.

http://www.tfd.chalmers.se/~hani/kur...nFoam%20v2.pdf

agustinvo October 27, 2015 05:31

Hello

I am dealing as well with natural convection problems, and I have to use polynomials to define my transport properties. I will perform LES on it.

I was able to create it, but I have some problems: I can't see an unsteady flow! It keeps laminar, steady. It must be related with my solver, but I have no more idea.

In any case, you can take a look as well to this:
http://www.cfd-online.com/Forums/ope...roperties.html

Where I talk about a compressible solver used as an incompressible one. It's not what we are looking for, but it is still something.


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