7.6.20.12.8. Casson

Syntax

Viscosity [{of} SpeciesName] = Casson [Mu_Zero = mu_zero | M = m | Shear_Reference = shear_reference | Yield_Stress = yield_stress | Skip_Sens_Iteration_Count = skip_sens_iteration_count]

Scope

Aria Material

Summary

A viscosity model dependent on the shear rate $\dot{\gamma}$

$\mu\left(\dot{\gamma}\right) = \left[\sqrt{\mu_\circ} + \sqrt{\tau_y / \dot{\gamma}}\left(1 - e^{-\sqrt{m\dot{\gamma}/\dot{\gamma}_{ref}}}\right) \right]^2,$

where $\mu_\infty$ is the infinite shear viscosity, $\mu_\circ$ is the zero shear viscosity, $\tau_y$ is the yield stress, $\dot{\gamma}_{ref}$ is a reference shear rate, and $m$ is a model parameter.

Parameter	Value	Default
{of}	{of \| species \| subindex}	–
SpeciesName	string	–
mu_zero	real	–
m	real	–
shear_reference	real	–
yield_stress	real	–
skip_sens_iteration_count	integer	0