Wall Lubrication Force Model Reference

The Wall Lubrication Force is the force that a rising bubble experiences that prevents it from touching the wall. This model is used for calculating interphase momentum transfer.

Table 1. Wall Lubrication Force Model Reference
Theory	See Wall Lubrication.
Provided By	[phase interaction] > Models > Optional Models
Example Node Path	[phase interaction] > Models > Wall Lubrication Force
Requires	Physics continuum selections: Material: Multiphase Multiphase Model: Eulerian Multiphase (EMP) (Automatically activates: Multiphase Interaction, Gradients.) Optional Models: Gravity Two Eulerian phases are required. A Continuous-Dispersed Topology or Multiple Flow Regime Topology phase interaction is required. Phase interaction selections: Optional Models: Lift Force Optional Models: Wall Lubrication Force
Properties	Formulation Option Available for Continuous-Dispersed Topology phase interactions only. See Wall Lubrication Force Properties.
Activates	Model Controls	For a Continuous-Dispersed phase interaction: Wall Lubrication Coefficient Available when the Formulation Option is set to Coefficient Based. For a Multiple Flow Regime phase interaction: First Dispersed Regime Wall Lubrication Coefficient Intermediate Regime Wall Lubrication Coefficient Second Dispersed Regime Wall Lubrication Coefficient See Wall Lubrication Coefficient Properties.
	Field Functions	See Wall Lubrication Field Functions.

Wall Lubrication Force Properties

Formulation Option

Specify the formulation to use for calculating the wall lubrication force.

This option is available for Continuous-Dispersed Topology phase interactions only. For Multiple Flow Regime Topology phase interactions, the Coefficient Based method is used.

Option	Description
Coefficient Based	Calculates the wall lubrication force using a coefficient-based method. You specify the method on the Wall Lubrication Coefficient node. See Wall Lubrication Coefficient Properties.
Lubchenko Available only when the Turbulent Dispersion Force model is activated and the Lift Force > Lift Correction method is set to Podowski Near Wall Adjustment.	Calculates the wall lubrication force using the Lubchenko formulation. There are no settings to specify. See Lubchenko Wall Lubrication.

Option

Description

Coefficient Based

Calculates the wall lubrication force using a coefficient-based method. You specify the method on the Wall Lubrication Coefficient node.

See Wall Lubrication Coefficient Properties.

Lubchenko

Available only when the Turbulent Dispersion Force model is activated and the Lift Force > Lift Correction method is set to Podowski Near Wall Adjustment.

Calculates the wall lubrication force using the Lubchenko formulation. There are no settings to specify.

See Lubchenko Wall Lubrication.

Wall Lubrication Coefficient Properties

Dimensions

The dimensionality of the wall lubrication coefficient (read-only).

Method

The method to use for calculating the wall lubrication coefficient.

Method	Corresponding Method Node
Antal Available for Continuous-Dispersed Topology phase interactions only.	Antal Defines the coefficient using the Antal correlation. You specify the coefficients for $C_{w 1}$ and $C_{w 2}$ in Eqn. (2033). This is the default setting.
Field Function	Field Function Defines the coefficient using a field function. You specify a function for $C_{W L}$ in Eqn. (2031).
Constant Available for Multiple Flow Regime Topology phase interactions only.	Constant Defines the coefficient as a constant value.

Wall Lubrication Field Functions

Wall Lubrication Coefficient of [phase interaction]: The wall lubrication coefficient, $C_{W L}$ in Eqn. (2031).