Hi everyone,

I want to use FEATool to simulate Joule heating (resistive heating) of 3D structures.

The procedure similar to the tutorial (

https://www.featool.com/doc/Multiphysics_01_resistive_heating1) works quite well. Here we introduce a heat term corresponding to the gradient of the electric field (step 29 of the tutorial).

However, when I try to solve this using the Fenics solver it returns an error:

NameError: name 'Vx' is not defined. Did you mean: 'dx'?

How can I change the syntax to tell the Fenics solver to use the actual derivative of the electric field?

Do I also have to solve this iteratively (first electric field, then heat)?

PS.: when changing the script in the Fenics GUI and deleting the Vx, Vy, and Vz the solver converges and gives a solution (not the correct one obviously).

Thank you very much in advance.

I would be very grateful for all the help concerning the Fenics solver as well as combining multiple physics in FEATool.