Boundary Condition (variable Umax)

Eli · April 3, 2010, 15:29

Hi Pals
I wanna set an expression for inlet boundary condition.
that's it:
u=Umax(t)[1-r^2/R^2]

No problem so far!
but I want it to pick up the Umax(t) from the specified cyclic curve in every timestep!
How can I do that?

thanks alot

ghorrocks · April 4, 2010, 07:35

If you know the Umax function then write it as a CEL expression. Otherwise use an interpolation function to define the Umax expression.

Eli · April 4, 2010, 10:19

Thank you soooo much
I appreciate your help.
I think I should use an interpolation function.

Best regards

April 3, 2010, 15:29	Boundary Condition (variable Umax)	#1
Eli New Member Join Date: Mar 2009 Posts: 18 Rep Power: 17	Hi Pals I wanna set an expression for inlet boundary condition. that's it: u=Umax(t)[1-r^2/R^2] No problem so far! but I want it to pick up the Umax(t) from the specified cyclic curve in every timestep! How can I do that? thanks alot

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April 4, 2010, 07:35		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	If you know the Umax function then write it as a CEL expression. Otherwise use an interpolation function to define the Umax expression.

April 4, 2010, 10:19		#3
Eli New Member Join Date: Mar 2009 Posts: 18 Rep Power: 17	Thank you soooo much I appreciate your help. I think I should use an interpolation function. Best regards