I am now using Modelica with OpenModelica at work to describe electromagnetic systems and it is an excellent language and, with OpenModelica, a excellent graphical user environment. Sometimes I think of it like SPICE but for multi-physics systems.

The Modelica library is quite mature and complete and the numerical solvers included with OpenModelica robust and performing.

It looks me a while to learn it but now it is paying out.

In addition the fact that Modelica is a standard implemented by several suppliers with an open source application is also great to avoid vendor lock in so that is a technology on which is safe to invest as an engineer and as a company.