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unsteady behavior for a scalar with non-temporal source definition and steady BC?

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Old   December 27, 2017, 18:45
Default unsteady behavior for a scalar with non-temporal source definition and steady BC?
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ali
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Hi everyone,

I have defined a source term for a scalar that is not a function of time and the boundary conditions are also steady while, for some reason, the simulation is transient.
The results show that this particular scalar has transient behavior while, as I said, the boundary condition and the source term do not have temporal terms.

What could be the reason?

Thanks,
Ali
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Old   December 27, 2017, 21:30
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Alexander
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you may try to calculate it only once, on the first time step


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Old   December 28, 2017, 15:49
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I will do it and let you know what will happen.
But wouldn't it get transported downstream if the source is turned-off after the first time-step?
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Old   December 28, 2017, 20:39
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if under scalar you mean uds variable, than there should be no problem with such approach.
Once you calculate it, uds will store data.

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