# Interfaces#

## Bushing interface#

When a bushing interface is used to create links with other interfaces, the link property defining the link can be modified after the reduction. This is achieved by applying a distributed heat flux proportional to the difference of the mean temperature of each interface. Bushing and distributed (see below) interfaces are equivalent when used for the application of a heat flux. Bushing interfaces are recommended for applying heat fluxes and creating a stationary link between interfaces. Using bushing interfaces for convection loads leads to inaccurate results. The nodal values are calculated considering the mid nodes of the surface elements.

### Name#

Change the name of the interface. Consistent naming of the interfaces simplifies the handling of the links. Physics type shows if the interface is mechanical or thermal. Interface type shows if the interface is a bushing or a distributed interface.

### Interface topos#

Click on the select button to open the topo-picker. The selected topology is highlighted red.

Type to pick: Choose topology and click on the desired topology. If the topology is hidden click on a node of the topology. This selects all topologies in contact with this node. Click then on undesired topologies to deselect them.

### Coordinate System#

Local coordinate system of the interface. The following color code is used.

Color |
Direction |
Name |
---|---|---|

Red |
Axial |
u |

Green |
Transversal |
v |

Blue |
Normal |
w |

#### Select topologies#

Define the origin of the coordinate system. If it should be in the middle of two faces, click on both and it will automatically be in the middle of the selected topologies. The default topology is the topology selected as 6DOF interface.

#### Offset#

Move the origin of the coordinate system in x-, y- or z-direction of the local coordinate system.

#### Main/Second axis#

Define the direction of two axes of the local coordinate system compared to the global coordinate. The third axis is then given.

#### Result#

Show the resulting coordinate system.

#### Visible#

Show/Hide the coordinate system and scale the arrows of it.

### Gauss quadrature order#

Order of the numerical integration to calculate the nodal values at the interface.

### Visible#

Show/Hide the interface. In the field a DOF can be selected, which is then shown. The arrow scale can be changed in the arrow scale field.

### DOFs for reduction#

A ticked box means that the interface can transmit a temperature.

### Start calculation#

Start the calculation of nodal weights for the specific temperature distribution. When the calculation is finished, the * in front of the name of the interface disappears. If a * is present, the interface must be updated by running the calculation.

## Distributed Interface#

When a distributed interface is used to create links with other interfaces, the link property defining the link cannot be modified after the reduction. A consistent link matrix is created for a distributed interface. The nodal values are calculated considering the mid nodes of the surface elements. Distributed interfaces are recommended for applying convection loads between the surface and the environment. Using distributed interfaces is not supported for links between two interfaces.

### Name#

Change the name of the interface here. Consistent naming of the interfaces simplifies the handling of the links. Physics type shows if the interface is mechanical or thermal. Interface type shows if the interface is a bushing or a distributed interface.

### Interface topos#

Click on the select button to open the topo-picker. The selected topology is highlighted red.

Type to pick: Choose topology and click on the desired topology. If the topology is hidden click on a node of the topology. This selects all topologies in contact with this node. Click then on undesired topologies to deselect them.

### Coordinate System#

Local coordinate system of the interface. The following color code is used.

Color |
Direction |
Name |
---|---|---|

Red |
Axial |
u |

Green |
Transversal |
v |

Blue |
Normal |
w |

#### Select topologies#

Define the origin of the coordinate system. If it should be in the middle of two faces, click on both and it will automatically be in the middle of the selected topologies. The default topology is the topology selected as 6DOF interface.

#### Offset#

Move the origin of the coordinate system in x-, y- or z-direction of the local coordinate system.

#### Main/Second axis#

Define the direction of two axes of the local coordinate system compared to the global coordinate. The third axis is then given.

#### Result#

Show the resulting coordinate system.

#### Visible#

Show/Hide the coordinate system and scale the arrows of it.

### Gauss quadrature order#

Order of the numerical integration to calculate the nodal values at the interface.

### Visible#

Select if and how the interface should be shown.

### DOFs for reduction#

A ticked box means that the interface can transmit a temperature.

### Start calculation#

Start the calculation of nodal weights for the specific force distribution. When the calculation is finished, the * in front of the name of the interface disappears. If a * is present, the interface must be updated by running the calculation. Before the calculation starts, a link property has to be defined. The link property defining the link cannot be modified after the reduction.