Partial Fill Model

The Partial Fill model allows the simulation of viscous flows moving in a region they do not fully occupy. It facilitates simulation of injection molding, mixing, and compounding.

The model uses the Filled physics value to track which parts of the domain are wet, which are dry, and which are partially wet. The viscous liquid fully occupies the wet sections, so the viscous fluid models have full weight there. Partial Fill implements a Level Set method to track the wet regions.


Provided by	[physics continuum] > Models > Optional Models
Example Node Path	Continua > Physics > Models > Partial Fill
Requires	Space: Three Dimensional or Two Dimensional, or Axisymmetric Time: Implicit Unsteady Material: Liquid Flow: Viscous Flow
Key Properties	SUPG The value for the Streamline-Upwind-Petrov-Galerkin advection stabilization term. The default value is 1.0. Diffusion Exponent $d$ in Eqn. (1085). The default value is 0.1.
Activates	Physics Models	Automatically selected models: Equation of State: Constant Density Viscous Regime: Laminar
	Initial Conditions	`Filled`: see Partial Fill Initial Conditions
	Boundary Inputs	See Partial Fill Boundary Settings
	Solvers	Filling Solver
	Field Functions	Filled

Partial Fill Initial Conditions

Use this property to define the parts of the domain that are to be considered full at start time.

Filled

Method: The profile that is selected to determine the distribution of the Filled property in the domain.
Value: The volume fraction that is occupied by viscous fluid at the start of the simulation, a value ranging from 0 through 1. The default is 1.0.
Dimensions: The Filled value is non-dimensional.

Partial Fill Boundary Settings

Free Stream

Filling Condition Specification

Method	Corresponding Value Nodes
Impose no condition	None
Impose filling condition	Filled The volume fraction that is occupied by viscous fluid, a value ranging from 0 through 1. The default is 1.0.

Mass Flow Inlet and Velocity Inlet

Filled

Tracks which parts of the domain are "wet" (flagged with a 1), which are "dry" (flagged with a 0), and which are partially wet (between 0 and 1). The viscous liquid fully occupies the wet sections, so the viscous fluid models have full weight there. Partial Fill implements a Level Set method to track the wet regions.

Method: The profile that is selected to determine the distribution of the Filled property in the domain.
Value: The volume fraction that is occupied by viscous fluid, a value ranging from 0 through 1. The default is 1.0.
Dimensions: The Filled value is non-dimensional.

Filling Solver

The Filling Solver is exposed when you select the Partial Fill physics model.

Properties

Threshold: A value ranging from 0 to 1. When the fraction of a cell that is filled with the viscous liquid is above the threshold value, the cell is treated as part of the viscous flow. The default value is 0.5.
Solver Frozen: When On, the solver does not update any quantity during an iteration. It is Off by default. This is a debugging option that can result in non-recoverable errors and wrong solutions due to missing storage. See Finite Volume Solvers Reference for details.
Mass Iterations: The number of sub-steps that each time-step is divided into. To reach better accuracy, stability, and convergence of the level set scheme, each time step is sub-divided into multiple time intervals and then both pure advection and reinitialization stages are solved for these sub-steps. The default is 3.