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"Compile equations" not using the correct physics
Posted 16 mag 2011, 05:47 GMT-4 Version 4.1 1 Reply
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Hi,
In my model, I use 3 physics: "Electric currents", and twice "Electric circuit".
I want to couple a lumped resistance to my FEM model, which acts as electric generator. But first, I want to compute the internal resistance of my FEM model, to be able to match the lumped resistance to achieve impedance matching.
In my model tree, I have:
1) - Electric currents
2) - Electric circuit #1 (lumped resistance to act as load for the FEM electric generator)
3) - Electric circuit #2 (current source to compute internal resistance of FEM electric generator)
In the "Electric currents" physics, I defined a terminal to a circuit.
Both "Electric circuit" physics use this terminal, once connected to a resistor, and once to a current source.
In my study steps, I define first a stationary step, where only physics 1 and 3 are selected. I then have a second study step where only physics 1 and 2 are selected. In my first study step, although I deactivated physics 2 ("Use in this study" option unchecked), the "Compile equations" node keeps using the variables of the physics 2 to define the boundary conditions of the terminal node in the "Electric currents physics". So I am unable to compute what I want, because the "Compile equations" connects the wrong physics (i.e. physics 1&2 instead of 1&3).
Any clue how I can overcome this issue?
Thanks a lot.
Alois Pfenniger
In my model, I use 3 physics: "Electric currents", and twice "Electric circuit".
I want to couple a lumped resistance to my FEM model, which acts as electric generator. But first, I want to compute the internal resistance of my FEM model, to be able to match the lumped resistance to achieve impedance matching.
In my model tree, I have:
1) - Electric currents
2) - Electric circuit #1 (lumped resistance to act as load for the FEM electric generator)
3) - Electric circuit #2 (current source to compute internal resistance of FEM electric generator)
In the "Electric currents" physics, I defined a terminal to a circuit.
Both "Electric circuit" physics use this terminal, once connected to a resistor, and once to a current source.
In my study steps, I define first a stationary step, where only physics 1 and 3 are selected. I then have a second study step where only physics 1 and 2 are selected. In my first study step, although I deactivated physics 2 ("Use in this study" option unchecked), the "Compile equations" node keeps using the variables of the physics 2 to define the boundary conditions of the terminal node in the "Electric currents physics". So I am unable to compute what I want, because the "Compile equations" connects the wrong physics (i.e. physics 1&2 instead of 1&3).
Any clue how I can overcome this issue?
Thanks a lot.
Alois Pfenniger
1 Reply Last Post 16 mag 2011, 11:07 GMT-4