Those viscosity models are helpful, but I'm interested in some other ones as well. If you support those viscosity models is it possible for me to define my own? The "usual" Chemical Engineering technique is to define a shear rate dependant viscosity, which is what I imagine was done for the Carreau and Power law models. So is it possible for me to do the same: grab whatever parameter is used for the magnitude of the shear rate tensor, and use it to write a relationship for the viscosity and then let whatever non linear engine grind away on it, much like it does for the other non-Newtonian fluids?

The test case I would like to try is pretty straightforward: a cylindrical tank with a hole in the bottom, emptying under gravity. I'd be looking for a steady-state solution using some open boundary conditions on the top surface and outlet of the tank, so idealizing it as if I am constantly replenishing the tank in a way that the surface remains level.

As a minor issue, I see Caedium lets me look at stream lines. In the model tank problem, once in steady-state, I'm interested in the residence time distribution in the tank, so integrating along each stream line to find how much time a particular part of the fluid spent in the tank. Then, going further (not necessary for the moment), the rheology parameters are actually time dependant, so I would want to model them with how long a particular fluid element has been in the tank. I can imagine fudging this by defining a fictitious chemical concentration that starts at a constant value entering the tank with a simple linear decay rate, the using the concentration at any point as a surrogate for time. Anyway, would Caedium have either the native facilities to look at time along streamlines or allow me add a continuity equation to simulate chemical reactions along the way?