Cubit 16.18 User Documentation
In CUBIT, boundary conditions are applied to sidesets or nodesets. Sidesets and nodesets can contain geometry or mesh. This means that models can be remeshed without worrying about losing boundary condition data if the boundary condition is applied to a geometry-based sideset/nodeset.
The sideset/nodeset used by a boundary condition will be visible to the user, and the user can modify the sideset/nodeset separately from the boundary condition. Sidesets/nodesets can be assigned to (or removed from) a boundary condition at any time.
Boundary conditions are broken into four groups: Restraints, loads, contact, and cfd. Each restraint that is created will belong to a restraint set, each load will belong to a load set, and each contact definition will belong to a contact set. A boundary condition set consists of any number of restraints, contact pairs, and loads. CFD boundary conditions do not belong to boundary condition sets.
Table 1: Overview of boundary condition entities available in Cubit
| Entity | Description and scope |
| Acceleration | Creates an acceleration boundary condition (acts on a body, volume, surface, curve, or vertex) |
| Velocity | Creates a velocity boundary condition (acts on a body, volume, surface, curve, or vertex) |
| Boundary Condition Set | Creates a BC set (contains restraint, load and contact sets) |
| Contact Region | Creates a contact region between two surfaces or two curves |
| Contact Pair | Creates a contact pair between two previously defined contact regions |
| Displacement | Creates a displacement boundary condition (acts on a body, volume, surface, curve or vertex) |
| Temperature | Create a temperature boundary condition (acts on a surface, curve or vertex) |
| Force | Creates a force boundary condition (acts on a surface, curve or vertex) |
| Pressure | Creates a pressure boundary condition (acts on a surface or curve) |
| Heat flux | Creates a heat flux boundary condition (acts on a surface or curve) |
| Inlet Velocity | Creates an inlet velocity boundary condition (acts on a surface) |
| Inlet Pressure | Creates an inlet pressure boundary condition (acts on a surface) |
| Inlet Massflow | Creates an inlet massflow boundary condition (acts on a surface) |
| Outlet Pressure | Creates an outlet pressure boundary condition (acts on a surface) |
| Farfield Pressure | Creates a farfield pressure boundary condition (acts on a surface) |
| Symmetry | Creates a symmetry boundary condition (acts on a surface) |