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Defining Maxwell Stress Tensor as Global Equation
Posted Feb 15, 2011, 4:36 p.m. EST RF & Microwave Engineering Version 4.0a, Version 4.1 1 Reply
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I have defined MST as Global Equations:
Txx-->Dx*conj(Ex)+Bx*conj(Hx)-0.5*(D*conj(E)+B*conj(H))
Txy-->...
..
Tzz
When I try to simulate it I get the following error message:
"Failed to evaluate variable Jacobian.
- Variable: E
- Global scope"
I think E(electric field) is defined in the RF Module as a variable.
Is there something wrong with my syntax?
Thanks a lot,
Damla
Txx-->Dx*conj(Ex)+Bx*conj(Hx)-0.5*(D*conj(E)+B*conj(H))
Txy-->...
..
Tzz
When I try to simulate it I get the following error message:
"Failed to evaluate variable Jacobian.
- Variable: E
- Global scope"
I think E(electric field) is defined in the RF Module as a variable.
Is there something wrong with my syntax?
Thanks a lot,
Damla
1 Reply Last Post Feb 16, 2011, 1:07 a.m. EST
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Posted:
1 decade ago
Hi
I encounter such problems when I either
a) use by error some already defined COSMOL variables names
b) if I define some variables on a boundary and I use them on a domain
The latter is more tricky, when you define your variables, they can be defined locally or globally, they might have only a sens to be evaluated on a boundary, but you might need them globally (all over) to i.e. define a derivative (what is needed for the Jacobian) then you must use a linear or global extrusion to make your variable globally available, based on some mapping rule. Another way, but you need really to know what you are doing ;) is to use the nojac() operator, to exclude the variable from the Jacobian evaluation
--
Good luck
Ivar
I encounter such problems when I either
a) use by error some already defined COSMOL variables names
b) if I define some variables on a boundary and I use them on a domain
The latter is more tricky, when you define your variables, they can be defined locally or globally, they might have only a sens to be evaluated on a boundary, but you might need them globally (all over) to i.e. define a derivative (what is needed for the Jacobian) then you must use a linear or global extrusion to make your variable globally available, based on some mapping rule. Another way, but you need really to know what you are doing ;) is to use the nojac() operator, to exclude the variable from the Jacobian evaluation
--
Good luck
Ivar