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help with advection-diffusion equation

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Old   August 7, 2009, 03:18
Default help with advection-diffusion equation
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andrianomena
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Hi there,
I'm solving an advection-diffusion equation(temperature equation) but it always crashes!!!
Is it possible to solve an advection-diffusion equation?How?
Can somebody out there help me please?
Best Regards.
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Old   August 7, 2009, 11:15
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Antonio Martins
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Hi,

What are the boundary conditions, methods used, and other relevant information. Yiu have to give more information, otherwise I will not be able to help you.

Regards,

Titio
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Old   August 8, 2009, 06:18
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Sandy Lee
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Hi Titio, could you help me too? I want to simulate the true pressures in the domain but not some relative pressure values. What boundary conditions I should give. I gave a fixValue in inlet and a zerogradient in outlet, but the results are wrong. By the way, my problem is turbulence flows. Thanks a lot.
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Old   August 11, 2009, 05:54
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andrianomena
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Hi
Sorry for the delay in replying,
In fact I'm modeling a porous media and through it a gas is circulating.The porous media is moving slowly(the gas flowing in cross-flow) that's why I have to take into account the advection term in the media temp equation,there is also a convective transfer between the media and the gas
When I implement the temperature equation of the media without source it's ok but when I couple it with the gas temperature it crashes.
boundaries are
for T:fixedGradient at the inlet,fixedValue at the outlet
for Tg:zerogradient at the outlet,fixedValue at the inlet
Information:the inlet is the inlet of the gas flow!
Thanks!
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