I don't think Fluent will be the best option for TE modules,
I don't know much about ANSYS, and to be honest, I have never used it. But I know that the Maxwell Enterprise can gives you the physics requiered for modeling a TEG, this is :
1. Fourier's Law
2. the Heat Conduction Equation
3. Ohm's Law
4. The Continuity Equation in EM Theory
5. And the Conservation of Energy Equation (where you have to consider the TE Effect (Peltier and Seebeck Coefficients))
Again, I have never used ANSYS, so I don't know how much difficult (or easy) can be to stablish all the physics that you would need to simulate an TEG in ANSYS with Maxwell.
The problem is that I have heard that ANSYS is to straightfoward to learn from the first start.
In contrast;
I have simulated a small (9 pairs) TE module with COMSOL.
COMSOL is very friendly interphase, Is very friendly to built up the geometry there, and to set up the physics, even (from the 5.1 above I think) there is a coupled module of physics, with the 5 models i listed above. This is the Thermoelectric Effect Coupling (the name is something like that).
With COMSOL to simulate the Electric Potential, Electric Current, Temperature Distribution and Heat Flux is very easy, for TE modules ...
I don't know the specifics of your problem (meaning what other physics or sub-systems might be coupled to your TE modules), or the specific configuration.
But I'm sure that, if it is for academic use, COMSOL is a good place to start.