Domains

Domain entities divide the model into different domains during morphing.

Each domain contains either elements (for 1D, 2D, 3D, or general domains), a series of nodes (for edge domains), or a group of nodes (for global domains).

The shape of a domain changes when the handles associated with a domain move, which in turn changes the position of the nodes inside those domains.

Domains do not have an active or export state.

Domain Types

For 1D, 2D, and 3D domains, only elements of the appropriate type will be assigned to the domain. If selected elements of the correct type are already assigned to another domain, then they will be reassigned to the new domain.

Handles will automatically be created at the ends of the edge domains.
1D Domain
Group of 1D elements, such as bars and rigid elements.
2D Domain
Group of shell elements. When 2D domains are created, edge domains will also be created around the edges of the elements for the domains.
Figure 1 shows a 2D domain that has been created from the selected elements. You only need to select the elements that you want to be in the new domain. The elements are automatically assigned to the new domain, edge domains are created around it, and handles are added at appropriate positions on the edge domains. The 2D domain created allows for the creation of a bead by moving the two handles at the ends of the edge normal to the plane of the elements.


Figure 1.
3D Domain
Group of solid elements. When 3D domains are created, 2D domains will be created on their faces and edge domains will be created around the edges of the 2D domains.
General Domain
General domains can contain any type of element (1D, 2D, or 3D), but edges or faces are not created along with the general domain. General domains will respect 2D and edge domains and you may create edge domains inside general domains if you desire. Handles will be created for general domains where the domains contact other elements whether those elements are in domains or not. Where the general domain contacts elements outside of domains, a handle is created at every node on the interface. Where general domains contact elements in other domains, handles will be created at logical locations to ensure control of the general domain. Once created, general domains can be morphed just like any other domain, even though they may contain different element types.
Figure 2 shows a general domain that has been created for a connector consisting of two rigid spiders and a hexa element. Note the four-rectangle shaped icon (in the center) for the general domain. Two handles have been manually added at either end of the domain so that the domain can be morphed as needed. Moving either handle will cause the entire domain to stretch evenly across its length.


Figure 2.
Note: It is possible to include the shell elements as part of the general domain in addition to the hexa and rigid elements.
Edge Domain
Series of nodes that are commonly found along the edges of 2D and 3D domains. You are not able to create edge domains that are not attached to any 2D, 3D, or general domains.
Figure 3 shows an edge domain that has been created for the selected nodes. The nodes should be selected in order following the path of the edge domain without skipping over any nodes. HyperMesh automatically adds handles at the ends of the edge domain at points along the length where the angle and curvature direction change above the set threshold. The edge domain created allows for the creation of a bead by moving the two handles at the ends of the edge normal to the plane of the elements.


Figure 3.
Global Domain
Group of nodes.
You may create more than one global domain in a model, but no node may belong to more than one global domain. Global handles only affect the nodes assigned to their global domain.
If you only need to change the shape of your model in a general way, then you only need to create a global domain. For large models, automatically generating local domains for the full model, such as using the generate auto function, is time consuming and possibly unnecessary. If you only need to change a part of the model, then you only need to create domains for that part.
When creating a global domain, you have the option of having global handles automatically generated for you. HyperMesh will place these handles at the eight corners of a box surrounding the model and at areas of peak nodal density within the model.