Settings for Physics Interfaces and Coupling Features
When physics interfaces are added using the predefined couplings, specific settings are included with the physics interfaces and the coupling features.
However, if physics interfaces are added one at a time, followed by the coupling features, these modified settings may not be automatically included.
For example, if single Heat Transfer in Fluids and Laminar Flow interfaces are added, COMSOL Multiphysics adds an empty Multiphysics node. When you right-click this node, you can add the Nonisothermal Flow coupling feature, but the modified settings are not included. To get all the modified settings presented below automatically, you may instead right-click the component node, select Multiphysics Couplings, and add the Nonisothermal Flow coupling feature.
Table 8-1: Modified Settings for the Nonisothermal Flow interfaces
Physics or Coupling Interface
Modified Settings (if Any)
Heat Transfer in Solids
Discretization order from temperature Lagrange shape function is 1.
A Fluid feature is added with a empty default editable selection. The Absolute pressure, pA (Model Input section) and the Velocity field, u (Heat Convection section) are automatically set to the variables from the Nonisothermal Flow multiphysics coupling feature.
Heat Transfer in Fluids
The Absolute pressure, pA (Model Input section) and the Velocity field, u (Heat Convection section) are automatically set to the variables from the Nonisothermal Flow multiphysics coupling feature.
Laminar Flow / Turbulent Flow
In the Fluid Properties default feature, the Density, ρ is automatically set to the variable from the Nonisothermal Flow multiphysics coupling feature.
The Compressibility option of the fluid flow interface is set to Weakly Compressible.
Nonisothermal Flow
The fluid-flow and heat-transfer interfaces are preselected.
Note that these settings may be overridden if another predefined coupling is added.