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.

Create Domains

Create morphing domains.

From the Morph ribbon, click the arrow next to the Morph tool set name and select Domains.
In the Morph Domains dialog, select Create for Action.

Define the domain.


Option	Action
Type	Select the type of domain to be created. 1D Domains, 2D Domains, and 3D Domains Select a group of elements, or choose all elements. Then select the check box options, described individually. Connector Domains Select connectors to create domains, and select the method (independent, main, secondary, general, and cluster) in which handles are created and managed for the domain. This option allows you to create connector domains that behave the same as 1D domains, as in many cases the two are the same. Independent connector domains can be controlled individually. Secondary connector domains are dependent on main domains. Main connector domains control the behavior of secondary domains. Cluster connector domains are controlled together. Note: For the main and secondary options, both 1D and connector domains are treated the same way in terms of interacting with 2D domains. In addition, select whether or not to retain handles. Edge Domains Select a node list in order, from one end to the other. Note: The nodes do not have to be along the edge of a domain, but they should follow along element boundaries without skipping nodes. General Domains Select a group of elements, or choose all elements. Then select the check box options, described individually. Note: General domains can contain any type of element, therefore all elements will include all elements in the model (1D, 2D, and 3D). Global Domains Select a group of nodes, or choose all nodes; then, select whether you want to create (global) handles, or only the domain itself. Global and Local Domains Select a group of elements, or choose all elements, Then select the check box options, described individually. HyperMesh will create 1D, 2D, and 3D domains for the selected elements according to their type and then create a global domain governing all of the nodes of the selected elements. Local Domains Select a group of elements, or choose all elements. Then select the check box options, described individually. HyperMesh will create 1D, 2D, and 3D domains for the selected elements according to their type.
Divide by Domain	Create multiple new domains based on the domains that the selected elements already belong to. Figure 4. Example: Divide by Domains. The different colors represent each domain. The different colors in
Divide by Comps	Create new domains, divided along component boundaries. This can be combined with divide by domains so that one domain will be generated for each combination of component and domain.
Retain Handles	Keep any handles already generated. Clear this checkbox to delete old handles lying within the new domain when creating that domain.
Partition 2D Domains	Divide created 2D domains based on defined settings.

Click Create.

Edit Edges

Merge, split, or add handles to an edge domain.

From the Morph ribbon, click the arrow next to the Morph tool set name and select Domains.
In the Morph Domains dialog, select Edit Edges for Action.

Define the parameters.


Option	Action
Option	Add Handles Creating dependent handles on an edge domain speeds radius and curvature changes for the given edge. This is useful for radius changes on edge domains attached to domains that contain a large number of nodes. Merge The ends of the edge domains must meet at common nodes. Split The selected node must be on the given edge but cannot be on the end of the edge.
Domain	When splitting a domain, use this collector to select the domain to split. When merging domains or adding handles, use this collector to select the domains to merge or add handles to.
At Node	When splitting a domain, use this collector to select the node at which you wish the split to occur. The node selected when splitting edges must be on the given edge, but cannot be on the end of the edge.
Retain Handles	Do not delete the existing handles when the handles are recalculated.

Click Split.

Organize Domains

Combine domains and add or remove nodes and elements from domains.

Only the elements of the appropriate type for the domain will be organized. The model is automatically updated, and new edge domains and handles may be created after the elements are organized.

From the Morph ribbon, click the arrow next to the Morph tool set name and select Domains.
In the Morph Domains dialog, select Organize for Action.

Define the parameters.


Option	Action
Option	Select the type of function to perform. Options: Add Nodes/Elems Combine Domains Remove Nodes/Elems
Domain Type	Choose the type of domain. You can add/remove elems to local domains, or nodes to global domains. Restriction: Only available when Option is set to Add Nodes/Elems or Remove Nodes/Elems.
Select	When Option is set to Add Nodes/Elems, select the domain to which you wish to add nodes or elements. When Option is set to Combine Domains, select the domains you wish to combine.
Nodes	Add or remove nodes to/from global domains. Restriction: Only available when Option is set to Add Nodes/Elems or Remove Nodes/Elems.
Retain Handles	Keep any handles already generated. Clear this check box to delete old handles lying within the specified domain. Restriction: Only available when Option is set to Combine Domains.

Click Organize.

Update Domains

Remesh, smooth, subdivide, update 1D method, partition, reparameterize, update domain colors, or delete domains.

From the Morph ribbon, click the arrow next to the Morph tool set name and select Domains.
In the Morph Domains dialog, select Update for Action.

Select a function to perform.


Function	Action
Delete All	Delete all domains, and/or all morph entities, throughout the model.
Partition	Partitions 2D domains by dividing them along element edges where the angle between the elements exceeds the domain angle parameter or where the curvature changes from flat to positive or negative. The curve tolerance parameter is used to determine whether two elements are flat or curved. Curvature changes are ignored if the partitioning order parameter is set to "angle-based."
Remesh	Place the new elements into the domains of the old elements, and optionally allow you to preserve your saved shapes. If you remesh a 3D domain and have the new mesh type set to quads, the 2D domains on the surface of the 3D domain will be remeshed with quad elements. The inside of the 3D domain will be remeshed with a layer of pyramid elements (one quad face with four tria faces) with the rest of the inside remeshed with tetra elements. Note: For elements outside of domains where shells and solid elements are touching, remeshing may destroy the connectivity between the solid and shell elements. Covering the solid elements with a layer of shell elements will prevent this from happening. If the mesh is too distorted, such as when element angles exceed 175 degrees, it may not be possible to remesh the elements or domains. In those cases you can smooth the elements or domains before remeshing, morph your mesh in several steps while remeshing after each one, or morph the mesh to fix poor elements. Figure 5.
Reparameterize	Reparameterize domains if they have been edited. This keeps the handle influences updated and thus, in most cases, you will not need to reparameterize your domains manually. Reparameterizing affects the way that handles influence the nodes. If a domain is morphed a great deal, the handles may not influence the nodes in the way you might expect. For instance, if a node is moved from one side of the mesh to the other, it will still be influenced more heavily by the handles it was previously close to rather than by the handles it is currently near. If this happens, you may want to reparameterize the domain so that the handles close to the nodes will influence them more than the handles farther away from the nodes. Since reparameterizing can change shapes saved as handles, you will be asked whether you want to preserve those shapes as node perturbations. If you click yes the shape will be converted to node perturbations and remain essentially unchanged. If you click no the shape will still apply to handles, which will affect the model in a different way than before, thus changing the shape. Shapes saved as node perturbations are unaffected by reparameterization.
Set Colors	Define the color.
Smooth Mesh	Apply smoothing to the selected domains as a morph, which means that it can be undone and redone and will be saved as part of any shape. The kriging method of smoothing applies only to elements inside domains. If you wish to apply smoothing to elements outside of domains while using the kriging method for elements inside domains, choose one of the options which lists both the kriging method and another method, such as kriging + auto, which will perform kriging style smoothing on elements inside the domains and autodecide style smoothing on elements outside the domains. The squish corrected method of smoothing allows you to select which nodes are fixed in place during the smoothing process. When smoothing domains, the handle nodes will automatically be fixed, but you may optionally select the nodes on edge domains and face domains to be fixed as well as any nodes that lie on feature edges. You can also manually select any other nodes to remain fixed. When smoothing elements, no nodes will automatically be fixed, and you have the same options of which nodes to fix automatically. The squish corrected method also allows you to select whether to pursue the best element quality, the best smoothing speed, or a balance between the two.
Subdivide 3D	Subdivide 3D domains into several 3D domains depending on the shape of the 3D domain and the number of divisible 2D domains. When subdividing, a 2D domain will not be divided unless it is specified as being a divisible domain. Thus, the original face domains will be preserved. The maximum number of new domains is equal to the number of indivisible domains. In cases where a 3D element touches more than one indivisible 2D domain there may be fewer 3D domains created than the maximum. There can be cases where the 3D domain cannot be subdivided if an insufficient number of divisible 2D domains have been selected.
Update 1D/ Connector Method	Determine how handles are placed for the 1D and connector domain, and how the dependencies are assigned.

Based on the defined function, select or define the following options:


Option	Defined Function	Action
Divide by Comps	Partition	Create new domains, divided along component boundaries. This can be combined with divide by domains so that one domain will be generated for each combination of component and domain.
Divide by Domain	Partition	Create multiple new domains based on the domains that the selected elements already belong to. Figure 6. Example: Divide by Domains. The different colors represent each domain.
Divisible 2D Domains	Subdivide 3D	Select the 2D domains that you wish to divide. When subdividing, a 2D domain will not be divided unless it is specified as being a divisible domain. Thus, the original face domains will be preserved.
Select Domains	All	Select the domains that you wish to divide, for which you wish to update the 1D/connector domain method, that you wish partition, or that you wish to reparameterize. Selected 3D domains will be subdivided into several 3D domains depending on the shape of the 3D domain and the number of divisible 2D domains. The 1D/conn method determines how handles are placed for the 1D and connector domain and how the dependencies are assigned. See the parameters subpanel for an explanation of the different methods.
Select Entities	Remesh 2D/3D	Choose either Domains or Elements. If you choose elements, you should only select elements that are not inside domains, since doing so would remove those elements from their domains when they are remeshed.
Elem Size	Remesh 2D/3D	Specify the desired element size. Note: Available when Remesh is selected for Edge Options.
Select 1D/Connector Domain Method	1D Conn Method	Options: Independent, Secondary, Main, Cluster Choose how handles are placed for the 1D and connector domain and how the dependencies are assigned.
Iterations	Smooth Mesh	Specify a limit on the number of iterations when smoothing the mesh.
New Mesh Type	Remesh 2D/3D	Choose the type of mesh to use during remeshing.
Preserve Shape	Remesh 2D/3D	Preserve morphing shapes after the remesh. Otherwise, shapes may be lost.
Retain Handles	Subdivide 3D Partition	Do not delete the existing handles when the handles are recalculated.
Size Control	Remesh 2D/3D	Attempt to keep elements roughly similar in size during meshing.
Skew Control	Remesh 2D/3D	Avoid producing highly-skewed elements during meshing.
Smooth Method	Smooth Mesh	Auto Decide Select the best method. Size Corrected Create elements of roughly uniform size. Shape Corrected Create elements of roughly uniform shape. Angle Corrected Create elements of roughly uniform angle. QI Optimized Create elements that conform to preset element Quality Index criteria. Kriging Applies only to elements inside domains. Kriging+Auto Select the best method while using kriging algorithms. Kriging+Size Create elements of roughly uniform size while using kriging algorithms. Kriging+Shape Create elements of roughly uniform shape while using kriging algorithms. Kriging+Angle Create elements of roughly uniform angle while using kriging algorithms. Kriging+QIOpt Create elements that conform to preset element Quality Index criteria while using kriging algorithms. Squish Corrected Improve the element squish quality index of the selected domains or elements.
Edge Options	Remesh 2D/3D	Remesh Change the node seeding along edges in the model. Hold Edges Preserve edge node seeding.

Click Create.