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Poor convergence with temperature dependent density on modified pisoFOAM

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Old   February 8, 2010, 16:06
Default Poor convergence with temperature dependent density on modified pisoFOAM
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Ovie Doro
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Hi Foamers,

I have a modified version of pisoFOAM for an incompressible flow with heat transfer (i.e. solver includes an energy equation). The density of the fluid is temperature dependent so I modified my single phase transportModel to reflect this.

The problem is that when I run the code (I am trying to simulate 2-D channel flow between heated vertical plates - same temperature at both walls, with the inlet at the top and the flow exiting at the bottom section between the plates) my solution simply refuses to converge even after so many time steps. It fluctuates somewhat around a mean value. I also notice that the velocity close to the wall goes from approximately zero to a positive and then decreases to a negative value as you move from the walls to the center of the channel. I am not quite sure if this physically real and wonder if its the cause of my lack of convergence.

I need someone to please provide some insight.
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Last edited by ovie; February 8, 2010 at 16:21. Reason: to include a picture of the velocity profile
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Old   March 20, 2011, 04:19
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Maryam Mousazadeh
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hello ovie;
I want to simulate an incompressible nanofluid flow with heat transfer using simpleFoam (i.e. solver includes an energy equation).The conductivity and viscosity of the fluid is temperature dependent . I don't know haw can modify the solver and case directories to these properties become temperature dependent; would you help me?
kind regards
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