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How to Evaluate Dependent Variable at Different Position ?

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I am trying to model a 1-D pulsatile flow in a tube (vessel) by setting a Weak Form PDE and Time Discrete Formulation.

I get the error because I want to set the boundary conditions (for non-reflecting condition) depending on present and previous dependent values at extremeties positions {0;L} and with offset {0+dx1,L-dx2}, respectively. I have tried calling the last value of the dependent variable through prev(u2(dx1),1) but haven't been successful. Is this the right syntax?

"Unknown function or operator.
- Name: u2
- Feature: Time Discrete Solver 1 (sol1/td1)"

I have searched in forums but I with no success.

Thanks in advance.

0 Replies Last Post 25 gen 2017, 18:05 GMT-5
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Hello Augusto Barros

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