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Cold Glass Surface And Air Behavior

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Old   March 18, 2013, 10:51
Default Cold Glass Surface And Air Behavior
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Maher Al Taweel
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Hello!

I have a problem with a temperature and speed simulation of air. I want to simulate the behavior of the air in a large room (21 x 18 x 6). I have fix floor and wall temperatures. And I have a large glass surface with a low temperature around 270 K. Therefore, I would consider lifting forces with respect to gravity and density differences. The physical characteristics that I have chosen are:
Three dimensinal
gradients
steady
gas (air)
Coupled flow
turbulent
Reynolds-averaged Navier-Stokes
K-epsilon
Realizable k-epsilon two layer
Two-layer all y wall treatment
Gravity

After some itterationer Redisualen becomes very large and the simulation stops. How do I resolve this problem?
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Old   March 19, 2013, 07:39
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siamak rahimi ardkapan
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You can run the simulation first by changing the solvers to be first order. If it did not diverge, let it to be converged completely and then change it one by one to second order.
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Old   March 20, 2013, 08:39
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Maher Al Taweel
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Quote:
Originally Posted by siara817 View Post
You can run the simulation first by changing the solvers to be first order. If it did not diverge, let it to be converged completely and then change it one by one to second order.
Thanks, I changed the convergence accelerators from none to continuity convergence accelerator, and now it works.

Best regards
Maher A.
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