Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.
Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
Defining Maxwell Stress Tensor as Global Equation
Posted 15 feb 2011, 16:36 GMT-5 RF & Microwave Engineering Version 4.0a, Version 4.1 1 Reply
Please login with a confirmed email address before reporting spam
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 16 feb 2011, 01:07 GMT-5
Please login with a confirmed email address before reporting spam
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