Flow Coupling
The Flow Coupling multiphysics coupling () defines u and p variables in order to set the model inputs in the Heat Transfer interface (or when applicable, a chemical species transport interface). In addition it provides all the fluids quantities that may be needed by the Heat Transfer interface (for example, viscosity, turbulence parameters).
Settings
The Label is the default multiphysics coupling feature name.
The Name is used primarily as a scope prefix for variables defined by the coupling node. Refer to such variables in expressions using the pattern <name>.<variable_name>. In order to distinguish between variables belonging to different coupling nodes or 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 multiphysics coupling feature in the model) is fc1.
Coupled Interfaces
This section defines the physics involved in the multiphysics coupling. By default, the applicable physics interface is selected in the Source list to apply the Destination to its physics interface to establish the coupling.
You can also select None from either list to uncouple the node from a physics interface. If the physics interface is removed from the Model Builder — for example, Heat Transfer in Solids is deleted — then the Destination list defaults to None as there is nothing to couple to.
Whenever the Destination interface is a heat transfer interface, the Nonisothermal Flow coupling node should be preferred to Flow Coupling. Indeed, Nonisothermal Flow brings an optimized stabilization; supports natural convection, including Boussinesq approximation; supports turbulent flow (wall functions, effective thermal conductivity); and handles work due to the pressure forces and viscous dissipation.
When the Destination interface is a chemical species transport interface, a Reacting Flow coupling node should be used instead of Flow Coupling. See The Reacting Flow Multiphysics Interfaces in the CFD Module User’s Guide for more details.
Location in User Interface
Context menus
Multiphysics>Flow Coupling
when any of the following interface is added together with Heat Transfer in Solids (or another version of the Heat Transfer Interface):
Single-Phase Flow (any version)
Porous Media and Subsurface Flow, Brinkman Equations