Domain, Boundary, Edge, Point, and Pair Nodes for the Darcy’s Law Interface
The Darcy’s Law Interface has the following domain, boundary, edge, point, and pair nodes, these nodes are available from the Physics ribbon toolbar (Windows users), Physics context menu (Mac or Linux users), or right-click to access the context menu (all users).
Domain
•
Fluid and Matrix Properties
•
Gravity
•
Initial Values
•
Storage Model
•
Mass Source
•
Poroelastic Storage
•
Porous Electrode Coupling
•
Richards’ Equation Model
Note that some features are only available with certain COMSOL products (see https://www.comsol.com/products/specifications/).
Boundary, Edge, and Point
The following nodes (listed in alphabetical order) are available on exterior boundaries:
•
Atmosphere/Gauge
•
Cross Section
•
Electrode Surface Coupling
•
Flux Discontinuity
•
Fracture Flow
•
Hydraulic Head
•
Inlet
•
Interior Wall
•
Line Mass Source
•
Mass Flux
•
No Flow
•
Outlet
•
Pervious Layer
•
Point Mass Source
•
Precipitation
•
Pressure
•
Pressure Head
•
1
•
Symmetry
•
Thickness
•
Thin Barrier
1 This node is described for the Transport of Diluted Species Interface
Note that some features are only available with certain COMSOL products (see https://www.comsol.com/products/specifications/)!
The relevant physics interface condition at interior boundaries is continuity:
The continuity boundary condition ensures that the pressure and mass flux are continuous. In addition, the Pressure boundary condition is available on interior boundaries.
The continuity boundary condition provides continuity for the pressure and mass flux. In addition, the following boundary conditions are available on interior boundaries:
•
Pressure
•
Pressure Head
•
Hydraulic Head
•
Interior Wall
•
Pervious Layer
•
Flux Discontinuity
•
Fracture Flow
•
Thin Barrier
 
In general, to add a node, go to the Physics toolbar, no matter what operating system you are using. Subnodes are available by clicking the parent node and selecting it from the Attributes menu.
For axisymmetric components, COMSOL Multiphysics takes the axial symmetry boundaries (at r = 0) into account and automatically adds an Axial Symmetry node that is valid on the axial symmetry boundaries only.
In the COMSOL Multiphysics Reference Manual see Table 2-4 for links to common sections and Table 2-5 to common feature nodes. You can also search for information: press F1 to open the Help window or Ctrl+F1 to open the Documentation window.