Domain, Boundary, Edge, Point, and Pair Nodes for the Fracture Flow Interface
The Fracture Flow Interface has the domain, boundary, edge, point, and pair nodes 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).
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.
Domain
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Fracture
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Initial Values
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Mass Source
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Gravity
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Thickness
Storage Model and Mass Source are described for the Darcy’s Law interface and are applied to boundaries instead of domains.
Boundary Conditions
The boundary conditions for this physics interface are similar to the boundary conditions for The Darcy’s Law Interface but are applied to edges in 3D and points in 2D. Edges and points form the “boundaries” of the geometries where the Fracture Flow interface is defined, which are faces in 3D and boundaries in 2D.
In the descriptions for these nodes, replace the Boundary Selection section with the Edge Selection (3D) or Point Selection (2D) section when using the Fracture Flow interface.
The following nodes are available on exterior boundaries (edges and points) and described for The Darcy’s Law Interface:
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Pressure
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Pressure Head
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Hydraulic Head
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Inlet
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Outlet
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Mass Flux
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Symmetry
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No Flow (the default)
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Atmosphere/Gauge
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Pervious Layer
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Precipitation
Note that some of the boundary conditions mentioned above are only available for certain modules. For detailed information, see https://www.comsol.com/products/specifications/.
The relevant physics interface condition at interior edges is continuity. In addition, the following edge conditions are available on interior edges:
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Pressure
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Pervious Layer
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.