HyperXtrude supports six different models to describe the constitutive behavior of
polymers. The material models available in HyperXtrude are:

- Power law model
- Spriggs truncated power law model
- Carreau-Yasuda model
- Cross model
- Modified Cross model
- Herschel-Bulkley model
- ViscoElastic Model

All of these models use the effective shear rate of the flow field to compute the
dependency of viscosity on the shear rate. Viscosity, besides being a strong
function of the shear rate, also depends on the temperature of the material.
HyperXtrude has five different functions to describe the temperature dependency and
it can be used in conjunction with the models mentioned above. These functions
are:

- None
- Exp(Q/RT)
- WLF
- Exp(-Beta(DeltaT))
- Exp(TB/T)