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Simulation of thermoelectric system/ problems with pde-mode (coefficient-form)

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Hello,

i want to simulate an thermoelectric system (peltier-effect).
I want to use the pde-mode in the coefficient-form.
I`ve already inserted the coefficient-matrices.
Now, i have following problem:
When i try to compute the model following error appears:

Syntax error in expression.
- Expression: -((0)*mod1.Ttt+(0)*mod1.Utt+(0)*mod1.Tt+(0)*mod1.Ut+(0)*mod1.T+(0)*mod1.U+(0)*(mod1.Tx)+(0)*(mod1.Ty)+(0)*(mod1.Tz)+(0)*(mod1.Ux)+(0)*(mod1.Uy)+(0)*(mod1.Uz)-(sigma*((Ux^2+Uy^2+Uz^2)+seebeck*(Tx*Ux+Ty*Uy+Tz*Uz))))*test(mod1.T)-(((0+(lamda+(sigma*seebeck^2*T)*(mod1.Tx)+(0)*(mod1.Ty)+(0)*(mod1.Tz)+(sigma*seebeck*T)*(mod1.Ux)+(0)*(mod1.Uy)+(0)*(mod1.Uz)+(mod1.T)*(0)+(mod1.U)*(0)-(0)))*(test(mod1.Tx))+((0+(0)*(mod1.Tx)+(lamda+(sigma*seebeck^2*T)*(mod1.Ty)+(0)*(mod1.Tz)+(0)*(mod1.Ux)+(sigma*seebeck*T)*(mod1.Uy)+(0)*(mod1.Uz)+(mod1.T)*(0)+(mod1.U)*(0)-(0)))*(test(mod1.Ty))+((0+(0)*(mod1.Tx)+(0)*(mod1.Ty)+(lamda+(sigma*seebeck^2*T)*(mod1.Tz)+(0)*(mod1.Ux)+(0)*(mod1.Uy)+(sigma*seebeck*T)*(mod1.Uz)+(mod1.T)*(0)+(mod1.U)*(0)-(0)))*(test(mod1.Tz)))
- Subexpression: )
- Position: 747

I think the (syntax)-error is caused by the matrix "f"

I have entered as shown below:
f= sigma*((Ux^2+Uy^2+Uz^2)+seebeck*(Tx*Ux+Ty*Uy+Tz*Uz))
0

It describes the right-hand-side of the coefficient-form-pde:
The following picture shows this matrix i want to implement.
i.imgur.com/OD9j1.jpg

I hope someone can help me with this prolem, because im a comsol newbe.

The comsol-file is attached.

Thanking you in anticipation



0 Replies Last Post Sep 1, 2011, 6:31 a.m. EDT
COMSOL Moderator

Hello Martin Schnieders

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