The Thin-Film Flow, Domain (tff) interface (
), found under the
Thin-Film Flow branch (
) when adding a physics interface, is used to solve the Reynolds equation or the modified Reynolds equation in a narrow channel that is represented by a domain within the geometry. It is used for lubrication or gas damping simulations when the fluid channel is thin enough for the Reynolds equation or the Modified Reynolds equation to apply. The physics interface is available for 2D geometries.
When this physics interface is added, the following default nodes are also added in the Model Builder —
Fluid-Film Properties,
Border (the default boundary condition), and
Initial Values. Then, from the
Physics toolbar, add other nodes that implement, for example, boundary conditions. You can also right-click
Thin-Film Flow, Domain to select physics features from the context menu.
The Label is the default physics interface name.
The Name is used primarily as a scope prefix for variables defined by the physics interface. Refer to such physics interface variables in expressions using the pattern
<name>.<variable_name>. In order to distinguish between variables belonging to different physics interfaces, the
name string must be unique. Only letters, numbers, and underscores (_) are permitted in the
Name field. The first character must be a letter.
The default Name (for the first physics interface in the model) is
tff.
