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Oscillatory buondary condition

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Old   February 27, 2011, 09:24
Default Oscillatory buondary condition
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Hi everyone,

I've got to impose an oscillatory boundary condition across a conduit (e.g. a pressure outlet). So my function will be as 10Pa*sin(100*t) where t is time.

I don't know how to write my function down the software.

Could anyone help?

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Marco
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Old   February 28, 2011, 09:16
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Vinicius Girardi
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Hi Marco,

In the Field functions node, create a new one and in the description, set this: 10*sin(100*$Time)

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Vinicius
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Old   March 2, 2011, 11:58
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Thank you so much Vinicius, you've really been very helpful!!

I'll ask you another question, I know it could be trivial but unfortunately I'm just a beginner:

seen I'm performing an unsteady simulation, I bet I'll have a transitional and then an oscillatory regime, so I got to set the time of duration of the simulation, say it is 30 seconds, the time step, say it is 0,1 sec and the iterations per time step, say 50; is it right? Where should I give these values?

Thanks again

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Marco
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Old   March 2, 2011, 12:42
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Vinicius Girardi
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The Time-Step is defined in the solver node -> Implicity Unsteady solver, in its properties.

The Maximum Physical Time and the Maximum Inner iterations are defined in the stopping criteria node. Donīt forget to make inactive the maximum steps criteria....

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Vinicius
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Old   March 2, 2011, 16:38
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Thanks a lot! You've been very helpful!

Regards

Marco
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Old   March 2, 2011, 17:07
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Henry Arrigo
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Hello all,
I v same the same problem as Marco has. I want to impose a sinusoidal force on a body. In the external force node there is no possibility to bind a Field function. What s your suggestion please?
thank you all.
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