Oscillatory buondary condition

MarcoB · February 27, 2011, 08:24

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?

Regards

Marco

Vinicius · February 28, 2011, 08:16

Hi Marco,

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

Regards,

Vinicius

MarcoB · March 2, 2011, 10:58

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

Regards

Marco

Vinicius · March 2, 2011, 11:42

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. Don´t forget to make inactive the maximum steps criteria....

Regards,

Vinicius

MarcoB · March 2, 2011, 15:38

Thanks a lot! You've been very helpful!

Regards

Marco

Henry Arrigo · March 2, 2011, 16:07

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.

February 27, 2011, 08:24	Oscillatory buondary condition	#1
MarcoB New Member Join Date: Feb 2011 Posts: 3 Rep Power: 15	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 10Pasin(100t) where t is time. I don't know how to write my function down the software. Could anyone help? Regards Marco

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February 28, 2011, 08:16		#2
Vinicius Member Vinicius Girardi Join Date: Mar 2009 Location: Sao Paulo, Brazil Posts: 80 Rep Power: 17	Hi Marco, In the Field functions node, create a new one and in the description, set this: 10sin(100$Time) Regards, Vinicius

March 2, 2011, 10:58		#3
MarcoB New Member Join Date: Feb 2011 Posts: 3 Rep Power: 15	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 Regards Marco

March 2, 2011, 11:42		#4
Vinicius Member Vinicius Girardi Join Date: Mar 2009 Location: Sao Paulo, Brazil Posts: 80 Rep Power: 17	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. Don´t forget to make inactive the maximum steps criteria.... Regards, Vinicius

March 2, 2011, 15:38		#5
MarcoB New Member Join Date: Feb 2011 Posts: 3 Rep Power: 15	Thanks a lot! You've been very helpful! Regards Marco

March 2, 2011, 16:07		#6
Henry Arrigo Senior Member Henry Arrigo Join Date: Jun 2010 Location: Italy Posts: 100 Rep Power: 15	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.