Add a Multiphase Material node (
) under a
Materials node in a model component to add a definition of a material composed of two or more immiscible
phases. Instead of resolving the exact position in space of each phase, they are approximated by their
volume fraction, and the effective properties of the material are obtained from a set of
mixing rules.
The Volume fraction definition can either be
Locally defined, or controlled from a physics interface providing volume fractions, such as
Level Set,
Phase Field,
Ternary Phase Field, or
Phase Transport. The default is
Locally defined. When the volume fractions are defined locally, they can be specified as user inputs in each
Phase (Subnode) subnode, or in the phases table described below. The Multiphase Material will automatically constrain each volume fraction to be between 0 and 1.
Use the Constrained phase setting to control which phase does not have an explicit definition of its volume fraction, but gets the remaining volume fraction as 1 minus the sum of fractions from the other phases. The default is
First phase.
The Phases table displays a summary of all the phases in the material, the source of their material properties, and their volume fraction expression. See
Phase (Subnode) for more information.
The material properties in the multiphase material are defined by a mixing rule that depends on the volume fractions and one or more material properties of each phase.
When the Mixing rule for a material property is set to
From homogenized properties, enter values or expressions for the properties in the
Homogenized properties section.
From the Material list, choose the material to represent the homogenized material properties:
Locally defined (the default), or select any other material that you have added. Click the
Go to Material button (
) to move to the selected material’s node. Click the
Add Material from Library button (
) to add a material from the
Add Material from Library window. You can also click the downward arrow next to the button and choose
Blank Material to add a new blank material. In both cases, the added material becomes selected in the
Material list.
Material properties that use From homogenized properties instead of a specific mixing rule are shown in the
Homogenized Properties table. The properties are to be thought of as homogenized in some matter other than through the available mixing rules. When the
Material in the
Homogenized Material section is
Locally defined, enter values or expressions for the properties in the
Value column. You can also click the
Edit button (
) below the table to enter the property values.
). You can also select a row and click the Edit mixing rule button (
) under the table. The Edit mixing rule button (
) cannot be used if more than one row are selected, or if no row is selected. See The Edit Mixing Rule Dialog Box for more information on selecting mixing rules.