Slurry Viscosity Model Reference

For values of solid fraction lower than a critical solid volume fraction, the mixture is considered as a slurry, where solid grains are suspended in the melt with almost no interaction between them. Their effect on the flow is modeled as an additional viscosity using the Slurry Viscosity model.

Table 1. Slurry Viscosity Model Reference
Theory	See Slurry Viscosity Model.
Provided By	[phase name] > Models > Optional Models
Example Node Path	[phase name] > Models > Slurry Viscosity
Requires	The Melting-Solidification model activated in the Eulerian phase.
Properties	None.
Activates	Physics Models	Average Slurry Viscosity (in the physics continuum) See Average Slurry Viscosity Properties.
	Materials	Slurry Viscosity See Materials Properties.
	Field Functions	See Field Functions.

Average Slurry Viscosity Properties

A volume-weighted average slurry viscosity is computed based on the viscosities of each phase when melting or solidification is in progress.

Slurry Viscosity Under-Relaxation Factor: At each iteration, this value governs the extent to which the newly computed solution supplants the old solution. The default value is 0.7.

Material Properties

Slurry Viscosity (Phase)

The available methods are Field Function and Metzner.

The Metzner method has the following properties:

Use Switching Function
Activates the switching function for the combined use of the Metzner slurry viscosity model and the Carman-Kozeny mushy zone model.

See Switching Function for Metzner Slurry Viscosity and Carman-Kozeny Mushy Zone Permeability Model.
Switching Function: Critical Solid Fraction
The critical solid volume fraction ${α *}_{c r}$ (see Eqn. (2719)). The default value is 0.27 (for Aluminum alloy A201).
Crystal Constant A
The crystal constant $A$ which depends on the aspect ratio and surface roughness of the crystal (see Eqn. (2713)). The default value is 0.3 (for Aluminum alloy A201).
Switching Function: Constant s
The non-dimensional constant $s$ (see Eqn. (2719)). The default value is 100 because the shape is rather insensitive for values from 80 through 120.

Slurry Viscosity (Mixture): For simulations with two or more liquid phases, the slurry viscosity for one cell is taken as a volume-weighted average for the whole mixture.

Field Functions

Average Slurry Viscosity: The volume-weighted slurry viscosity of the mixture, which is calculated from the slurry viscosities of the component phases.
Slurry Viscosity of [phase]: The additional bulk viscosity due to the partial solidification of the phase.